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Glossary of WSA attributes |
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This Glossary alphabetically lists all attributes used in the UKIDSSDR10 database(s) held in the WSA. If you would like to have more information about the schema tables please use the UKIDSSDR10 Schema Browser (other Browser versions). |
| A | B | C | D | E | F | G | H | I | J | K | L | M |
| N | O | P | Q | R | S | T | U | V | W | X | Y | Z |
W | ||||||||
|---|---|---|---|---|---|---|---|---|
| Name | Schema Table | Database | Description | Type | Length | Unit | Default Value | Unified Content Descriptor |
| w1ba | allwise_sc2 | WISE | Axis ratio (b/a) of the elliptical aperture used to measure source in W1. | float | 8 | arcsec | ||
| w1cc_map | allwise_sc2 | WISE | Contamination and confusion map for this source in W1. This column contains the integer equivalent of the 9-bit binary number that specifies if the W1 measurement is believed to be contaminated by or a spurious detection of an image artifact. | int | 4 | |||
The elements of the binary array are: S 0 0 0 O H 0 P D. The leftmost bit, S, differentiates whether the band-detection is believed to be a real detection contaminated by an artifact ("0") or a spurious detection of an artifact ("1"). The remaining bits are set to "1" to denote contamination by different types of artifacts according to the letters:
For example, a measurement that is believed to be a spurious detection of a diffraction spike and scattered light halo has a binary bit map value of "100001001" and w?cc_map=265. | ||||||||
| w1cc_map_str | allwise_sc2 | WISE | Contamination and confusion string. This column is a character string that denotes all artifacts that may contaminate the W1 measurement of this source, in the priority order D,P,H,O,d,p,h,o. Lower-case letters denote cases where the source detection in this band is believed to be real but the measurement may be contaminated by the artifact. upper-case letters denote cases where the source detection in this band may be a spurious detection of an artifact. This string is "null" if there are no artifacts that affect the measurement in this band. The value that appears in first element of the cc_flags string is the left-most character in w1cc_map_str. If w1cc_map_str is "null", then the corresponding cc_flags entry is "0". | varchar | 9 | |||
| For example, a real detection that is contaminated by a diffraction spike and a latent (persistent) image has a w?cc_map_str="dp". A spurious detection of a diffraction spike that is also contaminated by a latent image has w?cc_map_str="Dp". | ||||||||
| w1conf | allwise_sc2 | WISE | Estimated confusion noise in the W1 sky background annulus, in digital numbers. This number is the difference between the measured noise in the sky background w1sigsk and the noise measured in the same region on the Atlas Uncertainty Maps. | float | 8 | dn | ||
| w1cov | allwise_sc2 | WISE | Mean pixel coverage in W1. This column gives the mean pixel value from the W1 Atlas Tile Coverage Map within the "standard" aperture, a circular area with a radius of 8.25" centered on the position of this source. | float | 8 | |||
| W1cov may differ from the integer frame coverage value given in w1m for two reasons. First, individual pixels in the measurement area may be masked or otherwise unusable, reducing the effective pixel count and thus the mean coverage value. Second, the effective sky area sampled by a pixels in single-exposure image varies across the focal plane because of field distortion. Distortion is corrected when coadding to generate the Atlas Images. Therefore, the effective number of pixels contributing to a pixel in the Atlas Coverage Map may be slightly smaller or larger than expected if there was no distortion. Third, the values of w1m may be artificially reduced for sources that are covered by saturated 3-Band Cryo single-exposures. | ||||||||
| w1flg | allwise_sc2 | WISE | W1 "standard" aperture measurement quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w1flg_1 | allwise_sc2 | WISE | W1 5.5" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w1flg_2 | allwise_sc2 | WISE | W1 8.25" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w1flg_3 | allwise_sc2 | WISE | W1 11.0" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w1flg_4 | allwise_sc2 | WISE | W1 13.75" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w1flg_5 | allwise_sc2 | WISE | W1 16.5" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w1flg_6 | allwise_sc2 | WISE | W1 19.25" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w1flg_7 | allwise_sc2 | WISE | W1 22.0" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w1flg_8 | allwise_sc2 | WISE | W1 24.75" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w1flux | allwise_sc2 | WISE | The "raw" W1 source flux measured in profile-fit photometry in units of digital numbers. This value may be negative. This column is null if no useful profile-fit measurement of the source is possible because of masked or otherwise unusable pixels. | real | 4 | dn | ||
| w1gerr | allwise_sc2 | WISE | Uncertainty in the W1 magnitude of source measured in elliptical aperture. CAUTION: A w1gerr value of 9.999 indicates that the measurement uncertainty is very large, or the uncertainty could not be computed. In either case, the w1gmag measurement should be considered highly suspect. | float | 8 | mag | ||
| w1gflg | allwise_sc2 | WISE | W1 elliptical aperture measurement quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w1gmag | allwise_sc2 | WISE | W1 magnitude of source measured in the elliptical aperture described by w1rsemi, w1ba, and w1pa. | float | 8 | mag | ||
| w1k | allwise_sc2 | WISE | Stetson K variability index (Stetson, P. 1996, PASP, 108, 851) computed using the W1 profile-fit fluxes measured on the individual single-exposure images. This column is null if there are <3 single-exposure measurements available in W1. | float | 8 | |||
| w1m | allwise_sc2 | WISE | Integer frame coverage. This column gives the number of individual 7.7s W1 exposures on which a profile-fit measurement of this source was possible. This number can differ between the four bands because band-dependent criteria are used to select individual frames for inclusion in the coadded Atlas Images. This column is null if there is no frame coverage in this band at the position of this source. CAUTION: The value of w1m may be lower than expected for sources that were covered by saturated 3-Band Cryo single-exposures. A sign of this is if w1m differs significantly from w1cov. | int | 4 | |||
| w1mag | allwise_sc2 | WISE | W1 "standard" aperture magnitude. This is the curve-of-growth corrected source brightness measured in an 8.25" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". The curve-of-growth correction is given in w1mcor. This column is null if an aperture measurement was not possible in W1. | float | 8 | mag | ||
| w1mag_1 | allwise_sc2 | WISE | W1 5.5" radius aperture magnitude. This is the calibrated source brightness measured in a 5.5" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W1. | float | 8 | |||
| w1mag_2 | allwise_sc2 | WISE | W1 8.25" radius aperture magnitude. This is the calibrated source brightness measured in a 8.25" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W1. | float | 8 | mag | ||
| w1mag_3 | allwise_sc2 | WISE | W1 11.0" radius aperture magnitude. This is the calibrated source brightness measured in a 11.0" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W1. | float | 8 | mag | ||
| w1mag_4 | allwise_sc2 | WISE | W1 13.75" radius aperture magnitude. This is the calibrated source brightness measured in a 13.75" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W1. | float | 8 | mag | ||
| w1mag_5 | allwise_sc2 | WISE | W1 16.5" radius aperture magnitude. This is the calibrated source brightness measured in a 16.5" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W1. | float | 8 | mag | ||
| w1mag_6 | allwise_sc2 | WISE | W1 19.25" radius aperture magnitude. This is the calibrated source brightness measured in a 19.25" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W1. | float | 8 | mag | ||
| w1mag_7 | allwise_sc2 | WISE | W1 22.0" radius aperture magnitude. This is the calibrated source brightness measured in a 22.0" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W1. | float | 8 | mag | ||
| w1mag_8 | allwise_sc2 | WISE | W1 24.75" radius aperture magnitude. This is the calibrated source brightness measured in a 24.75" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W1. | float | 8 | mag | ||
| w1magp | allwise_sc2 | WISE | Magnitude computed from the inverse-variance-weighted mean of the profile-fit flux measurements on the w1m individual W1 frames covering this source. This differs from w1mpro in that it is computed by combining the profile-fit measurements from individual frames, whereas w1mpro is computed by fitting all W1 frames simultaneously and incorporating a robust error model. This column is "null" if w1m=0, the mean flux is negative or if no individual frame measurements are possible. CAUTION: This is not a robust measurement of source brightness. It is provided as an internal repeatability diagnostic only. Users should always defer to w1mpro for the optimal flux measurement for point sources. | float | 8 | mag | ||
| w1mcor | allwise_sc2 | WISE | W1 aperture curve-of-growth correction, in magnitudes. This correction is subtracted from the nominal 8.25" aperture photometry brightness, w1mag_2, to give the "standard-aperture" magnitude. | float | 8 | mag | ||
| w1mjdmax | allwise_sc2 | WISE | The latest modified Julian Date (mJD) of the W1 single-exposures covering the source. | float | 8 | |||
| w1mjdmean | allwise_sc2 | WISE | The average modified Julian Date (mJD) of the W1 single-exposures covering the source. | float | 8 | |||
| w1mjdmin | allwise_sc2 | WISE | The earliest modified Julian Date (mJD) of the W1 single-exposures covering the source. | float | 8 | |||
| w1mlq | allwise_sc2 | WISE | Probability measure that the source is variable in W1 flux. The value is -ln(Q), where Q = 1 - P(χ2). P is the cumulative chi-square distribution probability for the flux sample measured on the individual single-exposure images. The value is clipped at 9. | float | 8 | |||
| The Q value is the fraction of all cases to be at least as large as that observed if the null hypothesis is true. The null hypothesis is that the flux is emitted by a non-variable astrophysical object. It may be false because the object is a true variable. It may also be false because the flux measurement is corrupted by artifacts such as cosmic rays, scattered light, etc. The smaller the Q value, the more implausible the null hypothesis, i.e., the more likely it is that the flux is either variable or corrupted or both. | ||||||||
| w1mpro | allwise_sc2 | WISE | W1 magnitude measured with profile-fitting photometry, or the magnitude of the 95% confidence brightness upper limit if the W1 flux measurement has SNR<2. This column is null if the source is nominally detected in W1, but no useful brightness estimate could be made. | float | 8 | mag | ||
| NOTE: A special exception to the upper limit conditions described above applies if the W1 value of ph_qual is "Z" (e.g. ph_qual LIKE 'Z%'). In these cases, the value of w1mpro corresponds to the actual flux measurement, w1flux, or is null if w1flux is negative. This occurs for 106,140 sources in the AllWISE Catalog and 54,900 sources in the Reject Table, all of which are confined to a narrow strip of ecliptic longitude. | ||||||||
| w1ndf | allwise_sc2 | WISE | Number of degrees of freedom in the flux variability chi-square, W1. | int | 4 | |||
| w1nm | allwise_sc2 | WISE | Integer frame detection count. This column gives the number of individual 7.7s exposures on which this source was detected with SNR>3 in the W1 profile-fit measurement. This number can be zero for sources that are well-detected on the coadded Atlas Image, but too faint for detection on the single exposures. | int | 4 | |||
| w1pa | allwise_sc2 | WISE | Position angle (degrees E of N) of the elliptical aperture major axis used to measure source in W1. | float | 8 | deg | ||
| w1rchi2 | allwise_sc2 | WISE | Reduced χ2 of the W1 profile-fit photometry measurement. This column is null if the W1 magnitude is a 95% confidence upper limit (i.e. the source is not detected). | real | 4 | |||
| w1rchi2_pm | allwise_sc2 | WISE | Reduced χ2 of the W1 profile-fit photometry measurement including motion estimation. This column is null if the source is not detected in W1, or if the motion fit failed to converge or was not attempted. | real | 4 | |||
| w1rsemi | allwise_sc2 | WISE | Semi-major axis of the elliptical aperture used to measure source in W1. | float | 8 | arcsec | ||
| w1sat | allwise_sc2 | WISE | Saturated pixel fraction, W1. The fraction of all pixels within the profile-fitting area in the stack of single-exposure images used to characterize this source that are flagged as saturated. A value larger than 0.0 indicates one or more pixels of saturation. Saturation begins to occur for point sources brighter than [W1]~8 mag. Saturation may occur in fainter sources because of charged particle strikes, or if the source is covered by 3-Band Cryo single-exposures that began to saturate because of rising temperatures. | float | 8 | |||
| w1sigflux | allwise_sc2 | WISE | Uncertainty in the "raw" W1 source flux measurement in profile-fit photometry in units of digital numbers. This column is null if no useful profile-fit measurement of the source is possible because of masked or otherwise unusable pixels. | real | 4 | dn | ||
| w1sigm | allwise_sc2 | WISE | Uncertainty in the W1 "standard" aperture magnitude. This column is null if the W1 "standard" aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w1sigm_1 | allwise_sc2 | WISE | Uncertainty in the W1 5.5" radius aperture magnitude. This column is null if the the 5.5" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w1sigm_2 | allwise_sc2 | WISE | Uncertainty in the W1 8.25" radius aperture magnitude. This column is null if the the 8.25" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w1sigm_3 | allwise_sc2 | WISE | Uncertainty in the W1 11.0" radius aperture magnitude. This column is null if the the 11.0" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w1sigm_4 | allwise_sc2 | WISE | Uncertainty in the W1 13.75" radius aperture magnitude. This column is null if the the 13.75" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w1sigm_5 | allwise_sc2 | WISE | Uncertainty in the W1 16.5" radius aperture magnitude. This column is null if the the 16.5" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w1sigm_6 | allwise_sc2 | WISE | Uncertainty in the W1 19.25" radius aperture magnitude. This column is null if the the 19.25" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w1sigm_7 | allwise_sc2 | WISE | Uncertainty in the W1 22.0" radius aperture magnitude. This column is null if the the 22.0" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w1sigm_8 | allwise_sc2 | WISE | Uncertainty in the W1 24.75" radius aperture magnitude. This column is null if the the 24.75" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w1sigmpro | allwise_sc2 | WISE | W1 profile-fit photometric measurement uncertainty in mag units. This column is null if the W1 profile-fit magnitude is a 95% confidence upper limit or if the source is not measurable. | float | 8 | mag | ||
| Note - In a small number of cases where the W1 value of ph_qual is "Z" (e.g. ph_qual LIKE 'Z%'), the W1 source flux uncertainty was not measurable because of the presence of a large number of saturated pixels from 3-Band Cryo frames covered the source. In these cases, this column is null, but the w1mpro column will correspond either to the actual source flux, w1flux, rather than the 95% confidence upper limit, or will be null if w1flux is negative. | ||||||||
| w1sigp1 | allwise_sc2 | WISE | Standard deviation of the population of W1 fluxes measured on the w1m individual frames covering this source, in magnitudes. This provides a measure of the characteristic uncertainty of the measurement of this source on individual frames. This column is "null" if w1m<2 or if no individual frame measurements are possible. | float | 8 | mag | ||
| w1sigp2 | allwise_sc2 | WISE | Standard deviation of the mean of the distribution of W1 fluxes (w1magp) computed from profile-fit measurements on the w1m individual frames covering this source, in magnitudes. This is equivalent to w1sigp1/sqrt(w1m). This column is "null" if w1m<2 or if no individual frame measurements are possible. | float | 8 | mag | ||
| w1sigsk | allwise_sc2 | WISE | The uncertainty in the W1 sky background value in units of digital numbers measured in an annulus with an inner radius of 50" and outer radius of 70". | float | 8 | dn | ||
| w1sky | allwise_sc2 | WISE | The trimmed average of the W1 sky background value in digital numbers measured in an annulus with an inner radius of 50" and outer radius of 70". Both profile-fit and aperture photometry source brightness measurements are made relative to this sky background value. | float | 8 | dn | ||
| For profile-fit photometry, the sky background is measured on the individual single-exposure images that are used for source characterization. For aperture photometry, the sky background is measured on the Atlas Image. | ||||||||
| w1snr | allwise_sc2 | WISE | W1 profile-fit measurement signal-to-noise ratio. This value is the ratio of the flux (w1flux) to flux uncertainty (w1sigflux)in the W1 profile-fit photometry measurement. This column is null if w1flux is negative, or if w1flux or w1sigflux are null. | float | 8 | |||
| w2ba | allwise_sc2 | WISE | Axis ratio (b/a) of the elliptical aperture used to measure source in W2. | float | 8 | arcsec | ||
| w2cc_map | allwise_sc2 | WISE | Contamination and confusion map for this source in W2. This column contains the integer equivalent of the 9-bit binary number that specifies if the W2 measurement is believed to be contaminated by or a spurious detection of an image artifact. | int | 4 | |||
The elements of the binary array are: S 0 0 0 O H 0 P D. The leftmost bit, S, differentiates whether the band-detection is believed to be a real detection contaminated by an artifact ("0") or a spurious detection of an artifact ("1"). The remaining bits are set to "1" to denote contamination by different types of artifacts according to the letters:
For example, a measurement that is believed to be a spurious detection of a diffraction spike and scattered light halo has a binary bit map value of "100001001" and w?cc_map=265. | ||||||||
| w2cc_map_str | allwise_sc2 | WISE | Contamination and confusion string. This column is a character string that denotes all artifacts that may contaminate the W2 measurement of this source, in the priority order D,P,H,O,d,p,h,o. Lower-case letters denote cases where the source detection in this band is believed to be real but the measurement may be contaminated by the artifact. Upper-case letters denote cases where the source detection in this band may be a spurious detection of an artifact. This string is "null" if there are no artifacts that affect the measurement in this band. The value that appears in second element of the cc_flags string is the left-most character in w2cc_map_str. If w2cc_map_str is "null", then the corresponding cc_flags entry is "0". | varchar | 9 | |||
| For example, a real detection that is contaminated by a diffraction spike and a latent (persistent) image has a w?cc_map_str="dp". A spurious detection of a diffraction spike that is also contaminated by a latent image has w?cc_map_str="Dp". | ||||||||
| w2conf | allwise_sc2 | WISE | Estimated confusion noise in the W2 sky background annulus, in digital numbers. This number is the difference between the measured noise in the sky background w2sigsk and the noise measured in the same region on the Atlas Uncertainty Maps. | float | 8 | dn | ||
| w2cov | allwise_sc2 | WISE | Mean pixel coverage in W2. This column gives the mean pixel value from the W2 Atlas Tile Coverage Map within the "standard" aperture, a circular area with a radius of 8.25" centered on the position of this source. | float | 8 | |||
| W2cov may differ from the integer frame coverage value given in w2m for two reasons. First, individual pixels in the measurement area may be masked or otherwise unusable, reducing the effective pixel count and thus the mean coverage value. Second, the effective sky area sampled by a pixels in single-exposure image varies across the focal plane because of field distortion. Distortion is corrected when coadding to generate the Atlas Images. Therefore, the effective number of pixels contributing to a pixel in the Atlas Coverage Map may be slightly smaller or larger than expected if there was no distortion. | ||||||||
| w2flg | allwise_sc2 | WISE | W2 "standard" aperture measurement quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w2flg_1 | allwise_sc2 | WISE | W2 5.5" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w2flg_2 | allwise_sc2 | WISE | W2 8.25" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w2flg_3 | allwise_sc2 | WISE | W2 11.0" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w2flg_4 | allwise_sc2 | WISE | W2 13.75" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w2flg_5 | allwise_sc2 | WISE | W2 16.5" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w2flg_6 | allwise_sc2 | WISE | W2 19.25" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w2flg_7 | allwise_sc2 | WISE | W2 22.0" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w2flg_8 | allwise_sc2 | WISE | W2 24.75" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w2flux | allwise_sc2 | WISE | The "raw" W2 source flux measured in profile-fit photometry in units of digital numbers. This value may be negative. This column is null if no useful profile-fit measurement of the source is possible because of masked or otherwise unusable pixels. | real | 4 | dn | ||
| w2gerr | allwise_sc2 | WISE | Uncertainty in the W2 magnitude of source measured in elliptical aperture. CAUTION: A w2gerr value of 9.999 indicates that the measurement uncertainty is very large, or the uncertainty could not be computed. In either case, the w2gmag measurement should be considered highly suspect. | float | 8 | mag | ||
| w2gflg | allwise_sc2 | WISE | W2 elliptical aperture measurement quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w2gmag | allwise_sc2 | WISE | W2 magnitude of source measured in the elliptical aperture described by w2rsemi, w2ba, and w2pa. | float | 8 | mag | ||
| w2k | allwise_sc2 | WISE | Stetson K variability index (Stetson, P. 1996, PASP, 108, 851) computed using the W2 profile-fit fluxes measured on the individual single-exposure images. This column is null if there are <3 single-exposure measurements available in W2. | float | 8 | |||
| w2m | allwise_sc2 | WISE | Integer frame coverage. This column gives the number of individual 7.7s W2 exposures on which a profile-fit measurement of this source was possible. This number can differ between the four bands because band-dependent criteria are used to select individual frames for inclusion in the coadded Atlas Images. This column is null if there is no frame coverage in this band at the position of this source. | int | 4 | |||
| w2mag | allwise_sc2 | WISE | W2 "standard" aperture magnitude. This is the curve-of-growth corrected source brightness measured in an 8.25" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". The curve-of-growth correction is given in w2mcor. This column is null if an aperture measurement was not possible in W2. | float | 8 | mag | ||
| w2mag_1 | allwise_sc2 | WISE | W2 5.5" radius aperture magnitude. This is the calibrated source brightness measured in a 5.5" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W2. | float | 8 | mag | ||
| w2mag_2 | allwise_sc2 | WISE | W2 8.25" radius aperture magnitude. This is the calibrated source brightness measured in a 8.25" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W2. | float | 8 | mag | ||
| w2mag_3 | allwise_sc2 | WISE | W2 11.0" radius aperture magnitude. This is the calibrated source brightness measured in a 11.0" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W2. | float | 8 | mag | ||
| w2mag_4 | allwise_sc2 | WISE | W2 13.75" radius aperture magnitude. This is the calibrated source brightness measured in a 13.75" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W2. | float | 8 | mag | ||
| w2mag_5 | allwise_sc2 | WISE | W2 16.5" radius aperture magnitude. This is the calibrated source brightness measured in a 16.5" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W2. | float | 8 | mag | ||
| w2mag_6 | allwise_sc2 | WISE | W2 19.25" radius aperture magnitude. This is the calibrated source brightness measured in a 19.25" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W2. | float | 8 | mag | ||
| w2mag_7 | allwise_sc2 | WISE | W2 22.0" radius aperture magnitude. This is the calibrated source brightness measured in a 22.0" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W2. | float | 8 | mag | ||
| w2mag_8 | allwise_sc2 | WISE | W2 24.75" radius aperture magnitude. This is the calibrated source brightness measured in a 24.75" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W2. | float | 8 | mag | ||
| w2magp | allwise_sc2 | WISE | Magnitude computed from the inverse-variance-weighted mean of the profile-fit flux measurements on the w2m individual W2 frames covering this source. This differs from w2mpro in that it is computed by combining the profile-fit measurements from individual frames, whereas w2mpro is computed by fitting all W2 frames simultaneously and incorporating a robust error model. This column is "null" if w2m=0, the mean flux is negative or if no individual frame measurements are possible. CAUTION: This is not a robust measurement of source brightness. It is provided as an internal repeatability diagnostic only. Users should always defer to w2mpro for the optimal flux measurement for point sources. | float | 8 | mag | ||
| w2mcor | allwise_sc2 | WISE | W2 aperture curve-of-growth correction, in magnitudes. This correction is subtracted from the nominal 8.25" aperture photometry brightness, w2mag_2, to give the "standard-aperture" magnitude. | float | 8 | mag | ||
| w2mjdmax | allwise_sc2 | WISE | The latest modified Julian Date (mJD) of the W2 single-exposures covering the source. | float | 8 | |||
| w2mjdmean | allwise_sc2 | WISE | The average modified Julian Date (mJD) of the W2 single-exposures covering the source. | float | 8 | |||
| w2mjdmin | allwise_sc2 | WISE | The earliest modified Julian Date (mJD) of the W2 single-exposures covering the source. | float | 8 | |||
| w2mlq | allwise_sc2 | WISE | Probability measure that the source is variable in W2 flux. The value is -ln(Q), where Q = 1 - P(χ2). P is the cumulative chi-square distribution probability for the flux sample measured on the individual single-exposure images. The value is clipped at 9. | float | 8 | |||
| The Q value is the fraction of all cases to be at least as large as that observed if the null hypothesis is true. The null hypothesis is that the flux is emitted by a non-variable astrophysical object. It may be false because the object is a true variable. It may also be false because the flux measurement is corrupted by artifacts such as cosmic rays, scattered light, etc. The smaller the Q value, the more implausible the null hypothesis, i.e., the more likely it is that the flux is either variable or corrupted or both. | ||||||||
| w2mpro | allwise_sc2 | WISE | W2 magnitude measured with profile-fitting photometry, or the magnitude of the 95% confidence brightness upper limit if the W2 flux measurement has SNR<2. This column is null if the source is nominally detected in W2, but no useful brightness estimate could be made. | float | 8 | mag | ||
| w2ndf | allwise_sc2 | WISE | Number of degrees of freedom in the flux variability chi-square, W2. | int | 4 | |||
| w2nm | allwise_sc2 | WISE | Integer frame detection count. This column gives the number of individual 7.7s exposures on which this source was detected with SNR>3 in the W2 profile-fit measurement. This number can be zero for sources that are well-detected on the coadded Atlas Image, but too faint for detection on the single exposures. | int | 4 | |||
| w2pa | allwise_sc2 | WISE | Position angle (degrees E of N) of the elliptical aperture major axis used to measure source in W2. | float | 8 | deg | ||
| w2rchi2 | allwise_sc2 | WISE | Reduced χ2 of the W2 profile-fit photometry measurement. This column is null if the W2 magnitude is a 95% confidence upper limit (i.e. the source is not detected). | real | 4 | |||
| w2rchi2_pm | allwise_sc2 | WISE | Reduced χ2 of the W2 profile-fit photometry measurement including motion estimation. This column is null if the source is not detected in W2 magnitude or if the motion fit failed to converge or was not attempted. | real | 4 | |||
| w2rsemi | allwise_sc2 | WISE | Semi-major axis of the elliptical aperture used to measure source in W2. | float | 8 | arcsec | ||
| w2sat | allwise_sc2 | WISE | Saturated pixel fraction, W2. The fraction of all pixels within the profile-fitting area in the stack of single-exposure images used to characterize this source that are flagged as saturated. A value larger than 0.0 indicates one or more pixels of saturation. Saturation begins to occur for point sources brighter than [W2]~7 mag. Saturation may occur in fainter sources because of charged particle strikes. | float | 8 | |||
| w2sigflux | allwise_sc2 | WISE | Uncertainty in the "raw" W2 source flux measurement in profile-fit photometry in units of digital numbers. This column is null if no useful profile-fit measurement of the source is possible because of masked or otherwise unusable pixels. | real | 4 | dn | ||
| w2sigm | allwise_sc2 | WISE | Uncertainty in the W2 "standard" aperture magnitude. This column is null if the W2 "standard" aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w2sigm_1 | allwise_sc2 | WISE | Uncertainty in the W2 5.5" radius aperture magnitude. This column is null if the the 5.5" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w2sigm_2 | allwise_sc2 | WISE | Uncertainty in the W2 8.25" radius aperture magnitude. This column is null if the the 8.25" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w2sigm_3 | allwise_sc2 | WISE | Uncertainty in the W2 11.0" radius aperture magnitude. This column is null if the the 11.0" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w2sigm_4 | allwise_sc2 | WISE | Uncertainty in the W2 13.75" radius aperture magnitude. This column is null if the the 13.75" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w2sigm_5 | allwise_sc2 | WISE | Uncertainty in the W2 16.5" radius aperture magnitude. This column is null if the the 16.5" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w2sigm_6 | allwise_sc2 | WISE | Uncertainty in the W2 19.25" radius aperture magnitude. This column is null if the the 19.25" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w2sigm_7 | allwise_sc2 | WISE | Uncertainty in the W2 22.0" radius aperture magnitude. This column is null if the the 22.0" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w2sigm_8 | allwise_sc2 | WISE | Uncertainty in the W2 24.75" radius aperture magnitude. This column is null if the the 24.75" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w2sigmpro | allwise_sc2 | WISE | W2 profile-fit photometric measurement uncertainty in mag units. This column is null if the W2 profile-fit magnitude is a 95% confidence upper limit or if the source is not measurable. | float | 8 | mag | ||
| w2sigp1 | allwise_sc2 | WISE | Standard deviation of the population of W2 fluxes measured on the w2m individual frames covering this source, in magnitudes. This provides a measure of the characteristic uncertainty of the measurement of this source on individual frames. This column is "null" if w2m<2 or if no individual frame measurements are possible. | float | 8 | mag | ||
| w2sigp2 | allwise_sc2 | WISE | Standard deviation of the mean of the distribution of W2 fluxes (w2magp) computed from profile-fit measurements on the w2m individual frames covering this source, in magnitudes. This is equivalent to w2sigp1/sqrt(w2m). This column is "null" if w2m<2 or if no individual frame measurements are possible. | float | 8 | mag | ||
| w2sigsk | allwise_sc2 | WISE | The uncertainty in the W2 sky background value in units of digital numbers measured in an annulus with an inner radius of 50" and outer radius of 70". | float | 8 | dn | ||
| w2sky | allwise_sc2 | WISE | The trimmed average of the W2 sky background value in digital numbers measured in an annulus with an inner radius of 50" and outer radius of 70". Both profile-fit and aperture photometry source brightness measurements are made relative to this sky background value. | float | 8 | dn | ||
| For profile-fit photometry, the sky background is measured on the individual single-exposure images that are used for source characterization. For aperture photometry, the sky background is measured on the Atlas Image. | ||||||||
| w2snr | allwise_sc2 | WISE | W2 profile-fit measurement signal-to-noise ratio. This value is the ratio of the flux (w2flux) to flux uncertainty (w2sigflux)in the W2 profile-fit photometry measurement. This column is null if w2flux is negative, or if w2flux or w2sigflux are null. | float | 8 | |||
| w3ba | allwise_sc2 | WISE | Axis ratio (b/a) of the elliptical aperture used to measure source in W3. | float | 8 | arcsec | ||
| w3cc_map | allwise_sc2 | WISE | Contamination and confusion map for this source in W3. This column contains the integer equivalent of the 9-bit binary number that specifies if the W3 measurement is believed to be contaminated by or a spurious detection of an image artifact. | int | 4 | |||
The elements of the binary array are: S 0 0 0 O H 0 P D. The leftmost bit, S, differentiates whether the band-detection is believed to be a real detection contaminated by an artifact ("0") or a spurious detection of an artifact ("1"). The remaining bits are set to "1" to denote contamination by different types of artifacts according to the letters:
For example, a measurement that is believed to be a spurious detection of a diffraction spike and scattered light halo has a binary bit map value of "100001001" and w?cc_map=265. | ||||||||
| w3cc_map_str | allwise_sc2 | WISE | Contamination and confusion string. This column is a character string that denotes all artifacts that may contaminate the W3 measurement of this source, in the priority order D,P,H,O,d,p,h,o. Lower-case letters denote cases where the source detection in this band is believed to be real but the measurement may be contaminated by the artifact. Upper-case letters denote cases where the source detection in this band may be a spurious detection of an artifact. This string is "null" if there are no artifacts that affect the measurement in this band. The value that appears in third element of the cc_flags string is the left-most character in w3cc_map_str. If w3cc_map_str is "null", then the corresponding cc_flags entry is "0". | varchar | 9 | |||
| For example, a real detection that is contaminated by a diffraction spike and a latent (persistent) image has a w?cc_map_str="dp". A spurious detection of a diffraction spike that is also contaminated by a latent image has w?cc_map_str="Dp". | ||||||||
| w3conf | allwise_sc2 | WISE | Estimated confusion noise in the W3 sky background annulus, in digital numbers. This number is the difference between the measured noise in the sky background w3sigsk and the noise measured in the same region on the Atlas Uncertainty Maps. | float | 8 | dn | ||
| w3cov | allwise_sc2 | WISE | Mean pixel coverage in W3. This column gives the mean pixel value from the W3 Atlas Tile Coverage Map within the "standard" aperture, a circular area with a radius of 8.25" centered on the position of this source. | float | 8 | |||
| W3cov may differ from the integer frame coverage value given in w3m for two reasons. First, individual pixels in the measurement area may be masked or otherwise unusable, reducing the effective pixel count and thus the mean coverage value. Second, the effective sky area sampled by a pixels in single-exposure image varies across the focal plane because of field distortion. Distortion is corrected when coadding to generate the Atlas Images. Therefore, the effective number of pixels contributing to a pixel in the Atlas Coverage Map may be slightly smaller or larger than expected if there was no distortion. | ||||||||
| w3flg | allwise_sc2 | WISE | W3 "standard" aperture measurement quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w3flg_1 | allwise_sc2 | WISE | W3 5.5" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w3flg_2 | allwise_sc2 | WISE | W3 8.25" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w3flg_3 | allwise_sc2 | WISE | W3 11.0" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w3flg_4 | allwise_sc2 | WISE | W3 13.75" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w3flg_5 | allwise_sc2 | WISE | W3 16.5" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w3flg_6 | allwise_sc2 | WISE | W3 19.25" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w3flg_7 | allwise_sc2 | WISE | W3 22.0" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w3flg_8 | allwise_sc2 | WISE | W3 24.75" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w3flux | allwise_sc2 | WISE | The "raw" W3 source flux measured in profile-fit photometry in units of digital numbers. This value may be negative. This column is null if no useful profile-fit measurement of the source is possible because of masked or otherwise unusable pixels. | real | 4 | dn | ||
| w3gerr | allwise_sc2 | WISE | Uncertainty in the W3 magnitude of source measured in elliptical aperture. CAUTION: A w3gerr value of 9.999 indicates that the measurement uncertainty is very large, or the uncertainty could not be computed. In either case, the w3gmag measurement should be considered highly suspect. | float | 8 | mag | ||
| w3gflg | allwise_sc2 | WISE | W3 elliptical aperture measurement quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w3gmag | allwise_sc2 | WISE | W3 magnitude of source measured in the elliptical aperture described by w3rsemi, w3ba, and w3pa. | float | 8 | mag | ||
| w3k | allwise_sc2 | WISE | Stetson K variability index (Stetson, P. 1996, PASP, 108, 851) computed using the W3 profile-fit fluxes measured on the individual single-exposure images. This column is null if there are <3 single-exposure measurements available in W3. | float | 8 | |||
| w3m | allwise_sc2 | WISE | Integer frame coverage. This column gives the number of individual 8.8s W3 exposures on which a profile-fit measurement of this source was possible. This number can differ between the four bands because band-dependent criteria are used to select individual frames for inclusion in the coadded Atlas Images. This column is null if there is no frame coverage in this band at the position of this source. | int | 4 | |||
| w3mag | allwise_sc2 | WISE | W3 "standard" aperture magnitude. This is the curve-of-growth corrected source brightness measured in an 8.25" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". The curve-of-growth correction is given in w3mcor. This column is null if an aperture measurement was not possible in W3. | float | 8 | mag | ||
| w3mag_1 | allwise_sc2 | WISE | W3 5.5" radius aperture magnitude. This is the calibrated source brightness measured in a 5.5" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W3. | float | 8 | mag | ||
| w3mag_2 | allwise_sc2 | WISE | W3 8.25" radius aperture magnitude. This is the calibrated source brightness measured in a 8.25" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W3. | float | 8 | mag | ||
| w3mag_3 | allwise_sc2 | WISE | W3 11.0" radius aperture magnitude. This is the calibrated source brightness measured in a 11.0" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W3. | float | 8 | mag | ||
| w3mag_4 | allwise_sc2 | WISE | W3 13.75" radius aperture magnitude. This is the calibrated source brightness measured in a 13.75" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W3. | float | 8 | mag | ||
| w3mag_5 | allwise_sc2 | WISE | W3 16.5" radius aperture magnitude. This is the calibrated source brightness measured in a 16.5" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W3. | float | 8 | mag | ||
| w3mag_6 | allwise_sc2 | WISE | W3 19.25" radius aperture magnitude. This is the calibrated source brightness measured in a 19.25" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W3. | float | 8 | mag | ||
| w3mag_7 | allwise_sc2 | WISE | W3 22.0" radius aperture magnitude. This is the calibrated source brightness measured in a 22.0" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W3. | float | 8 | mag | ||
| w3mag_8 | allwise_sc2 | WISE | W3 24.75" radius aperture magnitude. This is the calibrated source brightness measured in a 24.75" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W3. | float | 8 | mag | ||
| w3magp | allwise_sc2 | WISE | Magnitude computed from the inverse-variance-weighted mean of the profile-fit flux measurements on the w3m individual W3 frames covering this source. This differs from w3mpro in that it is computed by combining the profile-fit measurements from individual frames, whereas w3mpro is computed by fitting all W3 frames simultaneously and incorporating a robust error model. This column is "null" if w3m=0, the mean flux is negative or if no individual frame measurements are possible. CAUTION: This is not a robust measurement of source brightness. It is provided as an internal repeatability diagnostic only. Users should always defer to w3mpro for the optimal flux measurement for point sources. | float | 8 | mag | ||
| w3mcor | allwise_sc2 | WISE | W3 aperture curve-of-growth correction, in magnitudes. This correction is subtracted from the nominal 8.25" aperture photometry brightness, w3mag_2, to give the "standard-aperture" magnitude. | float | 8 | mag | ||
| w3mjdmax | allwise_sc2 | WISE | The latest modified Julian Date (mJD) of the W3 single-exposures covering the source. | float | 8 | |||
| w3mjdmean | allwise_sc2 | WISE | The average modified Julian Date (mJD) of the W3 single-exposures covering the source. | float | 8 | |||
| w3mjdmin | allwise_sc2 | WISE | The earliest modified Julian Date (mJD) of the W3 single-exposures covering the source. | float | 8 | |||
| w3mlq | allwise_sc2 | WISE | Probability measure that the source is variable in W3 flux. The value is -ln(Q), where Q = 1 - P(χ2). P is the cumulative chi-square distribution probability for the flux sample measured on the individual single-exposure images. The value is clipped at 9. | float | 8 | |||
| The Q value is the fraction of all cases to be at least as large as that observed if the null hypothesis is true. The null hypothesis is that the flux is emitted by a non-variable astrophysical object. It may be false because the object is a true variable. It may also be false because the flux measurement is corrupted by artifacts such as cosmic rays, scattered light, etc. The smaller the Q value, the more implausible the null hypothesis, i.e., the more likely it is that the flux is either variable or corrupted or both. | ||||||||
| w3mpro | allwise_sc2 | WISE | W3 magnitude measured with profile-fitting photometry, or the magnitude of the 95% confidence brightness upper limit if the W3 flux measurement has SNR<2. This column is null if the source is nominally detected in W3, but no useful brightness estimate could be made. | float | 8 | mag | ||
| w3ndf | allwise_sc2 | WISE | Number of degrees of freedom in the flux variability chi-square, W3. | int | 4 | |||
| w3nm | allwise_sc2 | WISE | Integer frame detection count. This column gives the number of individual 8.8s exposures on which this source was detected with SNR>3 in the W3 profile-fit measurement. This number can be zero for sources that are well-detected on the coadded Atlas Image, but too faint for detection on the single exposures. | int | 4 | |||
| w3pa | allwise_sc2 | WISE | Position angle (degrees E of N) of the elliptical aperture major axis used to measure source in W3. | float | 8 | deg | ||
| w3rchi2 | allwise_sc2 | WISE | Reduced χ2 of the W3 profile-fit photometry measurement. This column is null if the W3 magnitude is a 95% confidence upper limit (i.e. the source is not detected). | real | 4 | |||
| w3rchi2_pm | allwise_sc2 | WISE | Reduced χ2 of the W3 profile-fit photometry measurement including motion estimation. This column is null if the source is not detected in W3 or if the motion fit failed to converge or was not attempted. | real | 4 | |||
| w3rsemi | allwise_sc2 | WISE | Semi-major axis of the elliptical aperture used to measure source in W3. | float | 8 | arcsec | ||
| w3sat | allwise_sc2 | WISE | Saturated pixel fraction, W3. The fraction of all pixels within the profile-fitting area source in the stack of single-exposure images used to characterize this source that are flagged as saturated. A value larger than 0.0 indicates one or more pixels of saturation. Saturation begins to occur for point sources brighter than [W3]~4 mag. Saturation may occur in fainter sources because of charged particle strikes. | float | 8 | |||
| w3sigflux | allwise_sc2 | WISE | Uncertainty in the "raw" W3 source flux measurement in profile-fit photometry in units of digital numbers. This column is null if no useful profile-fit measurement of the source is possible because of masked or otherwise unusable pixels. | real | 4 | dn | ||
| w3sigm | allwise_sc2 | WISE | Uncertainty in the W3 "standard" aperture magnitude. This column is null if the W3 "standard" aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w3sigm_1 | allwise_sc2 | WISE | Uncertainty in the W3 5.5" radius aperture magnitude. This column is null if the the 5.5" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w3sigm_2 | allwise_sc2 | WISE | Uncertainty in the W3 8.25" radius aperture magnitude. This column is null if the the 8.25" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w3sigm_3 | allwise_sc2 | WISE | Uncertainty in the W3 11.0" radius aperture magnitude. This column is null if the the 11.0" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w3sigm_4 | allwise_sc2 | WISE | Uncertainty in the W3 13.75" radius aperture magnitude. This column is null if the the 13.75" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w3sigm_5 | allwise_sc2 | WISE | Uncertainty in the W3 16.5" radius aperture magnitude. This column is null if the the 16.5" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w3sigm_6 | allwise_sc2 | WISE | Uncertainty in the W3 19.25" radius aperture magnitude. This column is null if the the 19.25" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w3sigm_7 | allwise_sc2 | WISE | Uncertainty in the W3 22.0" radius aperture magnitude. This column is null if the the 22.0" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w3sigm_8 | allwise_sc2 | WISE | Uncertainty in the W3 24.75" radius aperture magnitude. This column is null if the the 24.75" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w3sigmpro | allwise_sc2 | WISE | W3 profile-fit photometric measurement uncertainty in mag units. This column is null if the W3 profile-fit magnitude is a 95% confidence upper limit or if the source is not measurable. | float | 8 | mag | ||
| w3sigp1 | allwise_sc2 | WISE | Standard deviation of the population of W3 fluxes measured on the w3m individual frames covering this source, in magnitudes. This provides a measure of the characteristic uncertainty of the measurement of this source on individual frames. This column is "null" if w3m<2 or if no individual frame measurements are possible. | float | 8 | mag | ||
| w3sigp2 | allwise_sc2 | WISE | Standard deviation of the mean of the distribution of W3 fluxes (w3magp) computed from profile-fit measurements on the w3m individual frames covering this source, in magnitudes. This is equivalent to w3sigp1/sqrt(w3m). This column is "null" if w3m<2 or if no individual frame measurements are possible. | float | 8 | mag | ||
| w3sigsk | allwise_sc2 | WISE | The uncertainty in the W3 sky background value in units of digital numbers measured in an annulus with an inner radius of 50" and outer radius of 70". | float | 8 | dn | ||
| w3sky | allwise_sc2 | WISE | The trimmed average of the W3 sky background value in digital numbers measured in an annulus with an inner radius of 50" and outer radius of 70". Both profile-fit and aperture photometry source brightness measurements are made relative to this sky background value. | float | 8 | dn | ||
| For profile-fit photometry, the sky background is measured on the individual single-exposure images that are used for source characterization. For aperture photometry, the sky background is measured on the Atlas Image. | ||||||||
| w3snr | allwise_sc2 | WISE | W3 profile-fit measurement signal-to-noise ratio. This value is the ratio of the flux (w3flux) to flux uncertainty (w3sigflux)in the W3 profile-fit photometry measurement. This column is null if w3flux is negative, or if w3flux or w3sigflux are null. | float | 8 | |||
| w4ba | allwise_sc2 | WISE | Axis ratio (b/a) of the elliptical aperture used to measure source in W4. | float | 8 | arcsec | ||
| w4cc_map | allwise_sc2 | WISE | Contamination and confusion map for this source in W4. This column contains the integer equivalent of the 9-bit binary number that specifies if the W4 measurement is believed to be contaminated by or a spurious detection of an image artifact. | int | 4 | |||
The elements of the binary array are: S 0 0 0 O H 0 P D. The leftmost bit, S, differentiates whether the band-detection is believed to be a real detection contaminated by an artifact ("0") or a spurious detection of an artifact ("1"). The remaining bits are set to "1" to denote contamination by different types of artifacts according to the letters:
For example, a measurement that is believed to be a spurious detection of a diffraction spike and scattered light halo has a binary bit map value of "100001001" and w?cc_map=265. | ||||||||
| w4cc_map_str | allwise_sc2 | WISE | Contamination and confusion string. This column is a character string that denotes all artifacts that may contaminate the W4 measurement of this source, in the priority order D,P,H,O,d,p,h,o. Lower-case letters denote cases where the source detection in this band is believed to be real but the measurement may be contaminated by the artifact. Upper-case letters denote cases where the source detection in this band may be a spurious detection of an artifact. This string is "null" if there are no artifacts that affect the measurement in this band. The value that appears in fourth element of the cc_flags string is the left-most character in w4cc_map_str. If w4cc_map_str is "null", then the corresponding cc_flags entry is "0". | varchar | 9 | |||
| For example, a real detection that is contaminated by a diffraction spike and a latent (persistent) image has a w?cc_map_str="dp". A spurious detection of a diffraction spike that is also contaminated by a latent image has w?cc_map_str="Dp". | ||||||||
| w4conf | allwise_sc2 | WISE | Estimated confusion noise in the W4 sky background annulus, in digital numbers. This number is the difference between the measured noise in the sky background w4sigsk and the noise measured in the same region on the Atlas Uncertainty Maps. | float | 8 | dn | ||
| w4cov | allwise_sc2 | WISE | Mean pixel coverage in W4. This column gives the mean pixel value from the W4 Atlas Tile Coverage Map within the "standard" aperture, a circular area with a radius of 16.5" centered on the position of this source. | float | 8 | |||
| W4cov may differ from the integer frame coverage value given in w4m for two reasons. First, individual pixels in the measurement area may be masked or otherwise unusable, reducing the effective pixel count and thus the mean coverage value. Second, the effective sky area sampled by a pixels in single-exposure image varies across the focal plane because of field distortion. Distortion is corrected when coadding to generate the Atlas Images. Therefore, the effective number of pixels contributing to a pixel in the Atlas Coverage Map may be slightly smaller or larger than expected if there was no distortion. | ||||||||
| w4flg | allwise_sc2 | WISE | W4 "standard" aperture measurement quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w4flg_1 | allwise_sc2 | WISE | W4 11.0" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w4flg_2 | allwise_sc2 | WISE | W4 16.5" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w4flg_3 | allwise_sc2 | WISE | W4 22.0" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w4flg_4 | allwise_sc2 | WISE | W4 27.5" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w4flg_5 | allwise_sc2 | WISE | W4 33.0" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w4flg_6 | allwise_sc2 | WISE | W4 38.5" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w4flg_7 | allwise_sc2 | WISE | W4 44.0" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w4flg_8 | allwise_sc2 | WISE | W4 49.5" radius aperture magnitude quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w4flux | allwise_sc2 | WISE | The "raw" W4 source flux measured in profile-fit photometry in units of digital numbers. This value may be negative. This column is null if no useful profile-fit measurement of the source is possible because of masked or otherwise unusable pixels. | real | 4 | dn | ||
| w4gerr | allwise_sc2 | WISE | Uncertainty in the W4 magnitude of source measured in elliptical aperture. CAUTION: A w4gerr value of 9.999 indicates that the measurement uncertainty is very large, or the uncertainty could not be computed. In either case, the w4gmag measurement should be considered highly suspect. | float | 8 | mag | ||
| w4gflg | allwise_sc2 | WISE | W4 elliptical aperture measurement quality flag. This flag indicates if one or more image pixels in the measurement aperture for this band is confused with nearby objects, is contaminated by saturated or otherwise unusable pixels, or is an upper limit. | int | 4 | |||
The flag value is an integer that is the combination of one or more of the following values that signify different conditions:
| ||||||||
| w4gmag | allwise_sc2 | WISE | W4 magnitude of source measured in the elliptical aperture described by w4rsemi, w4ba, and w4pa. | float | 8 | mag | ||
| w4k | allwise_sc2 | WISE | Stetson K variability index (Stetson, P. 1996, PASP, 108, 851) computed using the W4 profile-fit fluxes measured on the individual single-exposure images. This column is null if there are <3 single-exposure measurements available in W4. | float | 8 | |||
| w4m | allwise_sc2 | WISE | Integer frame coverage. This column gives the number of individual 8.8s W4 exposures on which a profile-fit measurement of this source was possible. This number can differ between the four bands because band-dependent criteria are used to select individual frames for inclusion in the coadded Atlas Images. This column is null if there is no frame coverage in this band at the position of this source. | int | 4 | |||
| w4mag | allwise_sc2 | WISE | W4 "standard" aperture magnitude. This is the curve-of-growth corrected source brightness measured in a 16.5" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". The curve-of-growth correction is given in w4mcor. This column is null if an aperture measurement was not possible in W4. | float | 8 | mag | ||
| w4mag_1 | allwise_sc2 | WISE | W4 11.0" radius aperture magnitude. This is the calibrated source brightness measured in a 11.0" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W4. | float | 8 | mag | ||
| w4mag_2 | allwise_sc2 | WISE | W4 16.5" radius aperture magnitude. This is the calibrated source brightness measured in a 16.5" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W4. | float | 8 | mag | ||
| w4mag_3 | allwise_sc2 | WISE | W4 22.0" radius aperture magnitude. This is the calibrated source brightness measured in a 22.0" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W4. | float | 8 | mag | ||
| w4mag_4 | allwise_sc2 | WISE | W4 27.5" radius aperture magnitude. This is the calibrated source brightness measured in a 27.5" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied.This column is null if an aperture measurement was not possible in W4. | float | 8 | mag | ||
| w4mag_5 | allwise_sc2 | WISE | W4 33.0" radius aperture magnitude. This is the calibrated source brightness measured in a 33.0" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W4. | float | 8 | mag | ||
| w4mag_6 | allwise_sc2 | WISE | W4 38.5" radius aperture magnitude. This is the calibrated source brightness measured in a 38.5" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W4. | float | 8 | mag | ||
| w4mag_7 | allwise_sc2 | WISE | W4 44.0" radius aperture magnitude. This is the calibrated source brightness measured in a 44.0" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W4. | float | 8 | mag | ||
| w4mag_8 | allwise_sc2 | WISE | W4 49.5" radius aperture magnitude. This is the calibrated source brightness measured in a 49.5" radius circular aperture centered on the source position on the Atlas Image. If the source is not detected in the aperture measurement, this is the 95% confidence upper limit to the brightness. The background sky reference level is measured in an annular region with inner radius of 50" and outer radius of 70". No curve-of-growth correction has been applied. This column is null if an aperture measurement was not possible in W4. | float | 8 | mag | ||
| w4magp | allwise_sc2 | WISE | Magnitude computed from the inverse-variance-weighted mean of the profile-fit flux measurements on the w4m individual W4 frames covering this source. This differs from w4mpro in that it is computed by combining the profile-fit measurements from individual frames, whereas w4mpro is computed by fitting all W4 frames simultaneously and incorporating a robust error model. This column is "null" if w4m=0, the mean flux is negative or if no individual frame measurements are possible. CAUTION: This is not a robust measurement of source brightness. It is provided as an internal repeatability diagnostic only. Users should always defer to w4mpro for the optimal flux measurement for point sources. | float | 8 | mag | ||
| w4mcor | allwise_sc2 | WISE | W4 aperture curve-of-growth correction, in magnitudes. This correction is subtracted from the nominal 16.5" aperture photometry brightness, w4mag_2, to give the "standard-aperture" magnitude. | float | 8 | mag | ||
| w4mjdmax | allwise_sc2 | WISE | The latest modified Julian Date (mJD) of the W4 single-exposures covering the source. | float | 8 | |||
| w4mjdmean | allwise_sc2 | WISE | The average modified Julian Date (mJD) of the W4 single-exposures covering the source. | float | 8 | |||
| w4mjdmin | allwise_sc2 | WISE | The earliest modified Julian Date (mJD) of the W4 single-exposures covering the source. | float | 8 | |||
| w4mlq | allwise_sc2 | WISE | Probability measure that the source is variable in W4 flux. The value is -ln(Q), where Q = 1 - P(χ2). P is the cumulative chi-square distribution probability for the flux sample measured on the individual single-exposure images. The value is clipped at 9. | float | 8 | |||
| The Q value is the fraction of all cases to be at least as large as that observed if the null hypothesis is true. The null hypothesis is that the flux is emitted by a non-variable astrophysical object. It may be false because the object is a true variable. It may also be false because the flux measurement is corrupted by artifacts such as cosmic rays, scattered light, etc. The smaller the Q value, the more implausible the null hypothesis, i.e., the more likely it is that the flux is either variable or corrupted or both. | ||||||||
| w4mpro | allwise_sc2 | WISE | W4 magnitude measured with profile-fitting photometry, or the magnitude of the 95% confidence brightness upper limit if the W4 flux measurement has SNR<2. This column is null if the source is nominally detected in W4, but no useful brightness estimate could be made. | float | 8 | mag | ||
| w4ndf | allwise_sc2 | WISE | Number of degrees of freedom in the flux variability chi-square, W4. | int | 4 | |||
| w4nm | allwise_sc2 | WISE | Integer frame detection count. This column gives the number of individual 8.8s exposures on which this source was detected with SNR>3 in the W4 profile-fit measurement. This number can be zero for sources that are well-detected on the coadded Atlas Image, but too faint for detection on the single exposures. | int | 4 | |||
| w4pa | allwise_sc2 | WISE | Position angle (degrees E of N) of the elliptical aperture major axis used to measure source in W4. | float | 8 | deg | ||
| w4rchi2 | allwise_sc2 | WISE | Reduced χ2 of the W4 profile-fit photometry measurement. This column is null if the W4 magnitude is a 95% confidence upper limit (i.e. the source is not detected). | real | 4 | |||
| w4rchi2_pm | allwise_sc2 | WISE | Reduced χ2 of the W4 profile-fit photometry measurement including motion estimation. This column is null if the source is not detected in W4 or if the motion fit failed to converge or was not attempted. | real | 4 | |||
| w4rsemi | allwise_sc2 | WISE | Semi-major axis of the elliptical aperture used to measure source in W4. | float | 8 | arcsec | ||
| w4sat | allwise_sc2 | WISE | Saturated pixel fraction, W4. The fraction of all pixels within the profile-fitting area in the stack of single-exposure images used to characterize this source that are flagged as saturated. A value larger than 0.0 indicates one or more pixels of saturation. Saturation begins to occur for point sources brighter than [W4]~0 mag. Saturation may occur in fainter sources because of charged particle strikes. | float | 8 | |||
| w4sigflux | allwise_sc2 | WISE | Uncertainty in the "raw" W4 source flux measurement in profile-fit photometry in units of digital numbers. This column is null if no useful profile-fit measurement of the source is possible because of masked or otherwise unusable pixels. | real | 4 | dn | ||
| w4sigm | allwise_sc2 | WISE | Uncertainty in the W4 "standard" aperture magnitude. This column is null if the W4 "standard" aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w4sigm_1 | allwise_sc2 | WISE | Uncertainty in the W4 11.0" radius aperture magnitude. This column is null if the the 11.0" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w4sigm_2 | allwise_sc2 | WISE | Uncertainty in the W4 16.5" radius aperture magnitude. This column is null if the the 16.5" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w4sigm_3 | allwise_sc2 | WISE | Uncertainty in the W4 22.0" radius aperture magnitude. This column is null if the the 22.0" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w4sigm_4 | allwise_sc2 | WISE | Uncertainty in the W4 27.5" radius aperture magnitude. This column is null if the the 27.5" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w4sigm_5 | allwise_sc2 | WISE | Uncertainty in the W4 33.0" radius aperture magnitude. This column is null if the the 33.0" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w4sigm_6 | allwise_sc2 | WISE | Uncertainty in the W4 38.5" radius aperture magnitude. This column is null if the the 38.5" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w4sigm_7 | allwise_sc2 | WISE | Uncertainty in the W4 44.0" radius aperture magnitude. This column is null if the the 44.0" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w4sigm_8 | allwise_sc2 | WISE | Uncertainty in the W4 49.5" radius aperture magnitude. This column is null if the the 49.5" radius aperture magnitude is an upper limit, or if an aperture measurement was not possible. | float | 8 | mag | ||
| w4sigmpro | allwise_sc2 | WISE | W4 profile-fit photometric measurement uncertainty in mag units. This column is null if the W4 profile-fit magnitude is a 95% confidence upper limit or if the source is not measurable. | float | 8 | mag | ||
| w4sigp1 | allwise_sc2 | WISE | Standard deviation of the population of W4 fluxes measured on the w4m individual frames covering this source, in magnitudes. This provides a measure of the characteristic uncertainty of the measurement of this source on individual frames. This column is "null" if w4m<2 or if no individual frame measurements are possible. | float | 8 | mag | ||
| w4sigp2 | allwise_sc2 | WISE | Standard deviation of the mean of the distribution of W4 fluxes (w4magp) computed from profile-fit measurements on the w4m individual frames covering this source, in magnitudes. This is equivalent to w4sigp1/sqrt(w4m). This column is "null" if w4m<2 or if no individual frame measurements are possible. | float | 8 | mag | ||
| w4sigsk | allwise_sc2 | WISE | The uncertainty in the W4 sky background value in units of digital numbers measured in an annulus with an inner radius of 50" and outer radius of 70". | float | 8 | dn | ||
| w4sky | allwise_sc2 | WISE | The trimmed average of the W4 sky background value in digital numbers measured in an annulus with an inner radius of 50" and outer radius of 70". Both profile-fit and aperture photometry source brightness measurements are made relative to this sky background value. | float | 8 | dn | ||
| For profile-fit photometry, the sky background is measured on the individual single-exposure images that are used for source characterization. For aperture photometry, the sky background is measured on the Atlas Image. | ||||||||
| w4snr | allwise_sc2 | WISE | W4 profile-fit measurement signal-to-noise ratio. This value is the ratio of the flux (w4flux) to flux uncertainty (w4sigflux)in the W4 photometry measurement. This column is null if w4flux is negative, or if w4flux or w4sigflux are null. | float | 8 | |||
| warnFlag | firstSource | FIRST | Warning flag indicating that the source may be a sidelobe of a nearby bright source. | varchar | 1 | CODE_MISC | ||
| wcs | RequiredDiffImage | WSA | CASU difference image tool option to specify use of implicit WCS in the input files (y/n; recommended value=y) | varchar | 1 | ?? | ||
| wcs | RequiredDiffImage | WSACalib | CASU difference image tool option to specify use of implicit WCS in the input files (y/n; recommended value=y) | varchar | 1 | ?? | ||
| wcs | RequiredDiffImage | WSATransit | CASU difference image tool option to specify use of implicit WCS in the input files (y/n; recommended value=y) | varchar | 1 | ?? | ||
| wcs | RequiredDiffImage | WSAUHS | CASU difference image tool option to specify use of implicit WCS in the input files (y/n; recommended value=y) | varchar | 1 | ?? | ||
| wcsAxes | Multiframe | WSA | Number of axes in world co-ordinate system {image primary HDU keyword: WCSAXES} | tinyint | 1 | 0 | ?? | |
| wcsAxes | Multiframe | WSACalib | Number of axes in world co-ordinate system {image primary HDU keyword: WCSAXES} | tinyint | 1 | 0 | ?? | |
| wcsAxes | Multiframe | WSATransit | Number of axes in world co-ordinate system {image primary HDU keyword: WCSAXES} | tinyint | 1 | 0 | ?? | |
| wcsAxes | Multiframe | WSAUHS | Number of axes in world co-ordinate system {image primary HDU keyword: WCSAXES} | tinyint | 1 | 0 | ?? | |
| wcsPass | CurrentAstrometry | WSACalib | Pass level of WCS {image extension keyword: WCSPASS} | tinyint | 1 | 0 | pos.wcs | |
| wcsPass | CurrentAstrometry | WSATransit | Pass level of WCS {image extension keyword: WCSPASS} | tinyint | 1 | 0 | pos.wcs | |
| wcsPass | CurrentAstrometry | WSAUHS | Pass level of WCS {image extension keyword: WCSPASS} | tinyint | 1 | 0 | pos.wcs | |
| wcsPass | CurrentAstrometry, PreviousAstrometry | WSA | Pass level of WCS {image extension keyword: WCSPASS} | tinyint | 1 | 0 | pos.wcs | |
| windDirection | Multiframe | WSA | Wind direction, azimuth {image primary HDU keyword: WIND_DIR} | real | 4 | deg | -0.9999995e9 | meta.note;obs |
| windDirection | Multiframe | WSACalib | Wind direction, azimuth {image primary HDU keyword: WIND_DIR} | real | 4 | deg | -0.9999995e9 | meta.note;obs |
| windDirection | Multiframe | WSATransit | Wind direction, azimuth {image primary HDU keyword: WIND_DIR} | real | 4 | deg | -0.9999995e9 | meta.note;obs |
| windDirection | Multiframe | WSAUHS | Wind direction, azimuth {image primary HDU keyword: WIND_DIR} | real | 4 | deg | -0.9999995e9 | meta.note;obs |
| windSpeed | Multiframe | WSA | Wind speed {image primary HDU keyword: WIND_SPD} | real | 4 | km/h | -0.9999995e9 | phys.veloc;arith.ratio |
| windSpeed | Multiframe | WSACalib | Wind speed {image primary HDU keyword: WIND_SPD} | real | 4 | km/h | -0.9999995e9 | phys.veloc;arith.ratio |
| windSpeed | Multiframe | WSATransit | Wind speed {image primary HDU keyword: WIND_SPD} | real | 4 | km/h | -0.9999995e9 | phys.veloc;arith.ratio |
| windSpeed | Multiframe | WSAUHS | Wind speed {image primary HDU keyword: WIND_SPD} | real | 4 | km/h | -0.9999995e9 | phys.veloc;arith.ratio |
| wx | allwise_sc2 | WISE | The x-pixel coordinate of this source on the Atlas Image. | float | 8 | pix | ||
| wy | allwise_sc2 | WISE | The y-pixel coordinate of this source on the Atlas Image. | float | 8 | pix | ||