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nonSurvey ** Announcement - Workshop: Science from UKIDSS II, 15-17 Dec 2008, London UK ** |
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Glossary of WSA attributes |
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This Glossary alphabetically lists all attributes used in the UKIDSSDR1 database(s) held in the WSA. If you would like to have more information about the schema tables please use the UKIDSSDR1 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 |
J | ||||||||
|---|---|---|---|---|---|---|---|---|
| Name | Schema Table | Database | Description | Type | Length | Unit | Default Value | Unified Content Descriptor |
| j_1AperMag3 | lasSource | WSA | Default point/extended source 1st epoch J aperture corrected mag (2.0 arcsec aperture diameter) If in doubt use this flux estimator |
real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| j_1AperMag3Err | lasSource | WSA | Error in default point/extended source 1st epoch J mag (2.0 arcsec aperture diameter) | real | 4 | mag | -0.9999995e9 | ERROR |
| j_1AperMag4 | lasSource | WSA | Extended source 1st epoch J aperture corrected mag (2.8 arcsec aperture diameter) | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| j_1AperMag4Err | lasSource | WSA | Error in extended source 1st epoch J mag (2.8 arcsec aperture diameter) | real | 4 | mag | -0.9999995e9 | ERROR |
| j_1AperMag6 | lasSource | WSA | Extended source 1st epoch J aperture corrected mag (5.7 arcsec aperture diameter) | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| j_1AperMag6Err | lasSource | WSA | Error in extended source 1st epoch J mag (5.7 arcsec aperture diameter) | real | 4 | mag | -0.9999995e9 | ERROR |
| j_1Class | lasSource, lasSourceRemeasurement | WSA | discrete image classification flag in 1st epoch J | smallint | 2 | -9999 | CLASS_MISC | |
| j_1ClassStat | lasSource, lasSourceRemeasurement | WSA | N(0,1) stellarness-of-profile statistic in 1st epoch J | real | 4 | -0.9999995e9 | STAT_PROP | |
| j_1Deblend | lasSource, lasSourceRemeasurement | WSA | flag indicating parent/child relation in 1st epoch J | int | 4 | -99999999 | CODE_MISC | |
| j_1Ell | lasSource, lasSourceRemeasurement | WSA | 1-b/a, where a/b=semi-major/minor axes in 1st epoch J | real | 4 | -0.9999995e9 | PHYS_ELLIPTICITY | |
| j_1eNum | lasMergeLog | WSA | the extension number of this 1st epoch J frame | tinyint | 1 | NUMBER | ||
| j_1ErrBits | lasSource, lasSourceRemeasurement | WSA | processing warning/error bitwise flags in 1st epoch J | int | 4 | -99999999 | CODE_MISC | |
| j_1Eta | lasSource | WSA | Offset of 1st epoch J detection from master position (+north/-south) | real | 4 | arcsec | -0.9999995e9 | POS_EQ_DEC_OFF |
| When associating individual passband detections into merged sources, a generous (in terms of the positional uncertainties) pairing radius of 2.0 (UKIDSS LAS and GPS; also non-survey programmes) or 1.0 (UKIDSS GPS, DXS and UDS) arcseconds is used, the higher value enabling pairing of moving sources when epoch separations may be several years. Such a large association criterion can of course lead to spurious pairings in the merged sources lists (although note that between passband pairs, handshake pairing is done: both passbands must agree that the candidate pair is their nearest neighbour for the pair to propagate through into the merged source table). In order to help filter spurious pairings out, and assuming that large positional offsets between the different passband detections are not expected (e.g. because of source motion, or larger than usual positional uncertainties) then the attributes Xi and Eta can be used to filter any pairings with suspiciously large offsets in one or more bands. For example, for a clean sample of QSOs from the LAS, you might wish to insist that the offsets in the selected sample are all below 1 arcsecond: simply add WHERE clauses into the SQL sample selection script to exclude all Xi and Eta values larger than the threshold you want. | ||||||||
| j_1Gausig | lasSource, lasSourceRemeasurement | WSA | RMS of axes of ellipse fit in 1st epoch J | real | 4 | pixels | -0.9999995e9 | MORPH_PARAM |
| j_1HallMag | lasSource | WSA | Total point source 1st epoch J mag | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| j_1HallMagErr | lasSource | WSA | Error in total point source 1st epoch J mag | real | 4 | mag | -0.9999995e9 | ERROR |
| j_1Mag | lasSourceRemeasurement | WSA | 1st epoch J mag (as appropriate for this merged source) | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| j_1MagErr | lasSourceRemeasurement | WSA | Error in 1st epoch J mag | real | 4 | mag | -0.9999995e9 | ERROR |
| j_1mfID | lasMergeLog | WSA | the UID of the relevant 1st epoch J multiframe | bigint | 8 | ID_FRAME | ||
| j_1mhExt | lasSource | WSA | Extended source colour J-H (using aperMag3) | real | 4 | mag | -0.9999995e9 | PHOT_COLOR |
| Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits. | ||||||||
| j_1mhExtErr | lasSource | WSA | Error on extended source colour J-H | real | 4 | mag | -0.9999995e9 | ERROR |
| Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits. | ||||||||
| j_1mhPnt | lasSource | WSA | Point source colour J-H (using aperMag3) | real | 4 | mag | -0.9999995e9 | PHOT_COLOR |
| Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits. | ||||||||
| j_1mhPntErr | lasSource | WSA | Error on point source colour J-H | real | 4 | mag | -0.9999995e9 | ERROR |
| Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits. | ||||||||
| j_1ObjID | lasSource | WSA | the UID of the 1st epoch J detection | bigint | 8 | -99999999 | ID_NUMBER | |
| j_1ObjID | lasSourceRemeasurement | WSA | the UID of the 1st epoch J remeasurement | bigint | 8 | -99999999 | ID_NUMBER | |
| j_1PA | lasSource, lasSourceRemeasurement | WSA | ellipse fit celestial orientation in 1st epoch J | real | 4 | Degrees | -0.9999995e9 | POS_POS-ANG |
| j_1PetroMag | lasSource | WSA | Extended source 1st epoch J mag (Petrosian) | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| j_1PetroMagErr | lasSource | WSA | Error in extended source 1st epoch J mag (Petrosian) | real | 4 | mag | -0.9999995e9 | ERROR |
| j_1ppErrBits | lasSource, lasSourceRemeasurement | WSA | additional WFAU post-processing error bits in 1st epoch J | int | 4 | 0 | CODE_MISC | |
| j_1PsfMag | lasSource | WSA | Point source profile-fitted 1st epoch J mag | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| j_1PsfMagErr | lasSource | WSA | Error in point source profile-fitted 1st epoch J mag | real | 4 | mag | -0.9999995e9 | ERROR |
| j_1SeqNum | lasSource | WSA | the running number of the 1st epoch J detection | int | 4 | -99999999 | ID_NUMBER | |
| j_1SeqNum | lasSourceRemeasurement | WSA | the running number of the 1st epoch J remeasurement | int | 4 | -99999999 | ID_NUMBER | |
| j_1SerMag2D | lasSource | WSA | Extended source 1st epoch J mag (profile-fitted) | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| j_1SerMag2DErr | lasSource | WSA | Error in extended source 1st epoch J mag (profile-fitted) | real | 4 | mag | -0.9999995e9 | ERROR |
| j_1Xi | lasSource | WSA | Offset of 1st epoch J detection from master position (+east/-west) | real | 4 | arcsec | -0.9999995e9 | POS_EQ_RA_OFF |
| When associating individual passband detections into merged sources, a generous (in terms of the positional uncertainties) pairing radius of 2.0 (UKIDSS LAS and GPS; also non-survey programmes) or 1.0 (UKIDSS GPS, DXS and UDS) arcseconds is used, the higher value enabling pairing of moving sources when epoch separations may be several years. Such a large association criterion can of course lead to spurious pairings in the merged sources lists (although note that between passband pairs, handshake pairing is done: both passbands must agree that the candidate pair is their nearest neighbour for the pair to propagate through into the merged source table). In order to help filter spurious pairings out, and assuming that large positional offsets between the different passband detections are not expected (e.g. because of source motion, or larger than usual positional uncertainties) then the attributes Xi and Eta can be used to filter any pairings with suspiciously large offsets in one or more bands. For example, for a clean sample of QSOs from the LAS, you might wish to insist that the offsets in the selected sample are all below 1 arcsecond: simply add WHERE clauses into the SQL sample selection script to exclude all Xi and Eta values larger than the threshold you want. | ||||||||
| j_2AperMag3 | lasSource | WSA | Default point/extended source 2nd epoch J aperture corrected mag (2.0 arcsec aperture diameter) If in doubt use this flux estimator |
real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| j_2AperMag3Err | lasSource | WSA | Error in default point/extended source 2nd epoch J mag (2.0 arcsec aperture diameter) | real | 4 | mag | -0.9999995e9 | ERROR |
| j_2AperMag4 | lasSource | WSA | Extended source 2nd epoch J aperture corrected mag (2.8 arcsec aperture diameter) | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| j_2AperMag4Err | lasSource | WSA | Error in extended source 2nd epoch J mag (2.8 arcsec aperture diameter) | real | 4 | mag | -0.9999995e9 | ERROR |
| j_2AperMag6 | lasSource | WSA | Extended source 2nd epoch J aperture corrected mag (5.7 arcsec aperture diameter) | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| j_2AperMag6Err | lasSource | WSA | Error in extended source 2nd epoch J mag (5.7 arcsec aperture diameter) | real | 4 | mag | -0.9999995e9 | ERROR |
| j_2Class | lasSource, lasSourceRemeasurement | WSA | discrete image classification flag in 2nd epoch J | smallint | 2 | -9999 | CLASS_MISC | |
| j_2ClassStat | lasSource, lasSourceRemeasurement | WSA | N(0,1) stellarness-of-profile statistic in 2nd epoch J | real | 4 | -0.9999995e9 | STAT_PROP | |
| j_2Deblend | lasSource, lasSourceRemeasurement | WSA | flag indicating parent/child relation in 2nd epoch J | int | 4 | -99999999 | CODE_MISC | |
| j_2Ell | lasSource, lasSourceRemeasurement | WSA | 1-b/a, where a/b=semi-major/minor axes in 2nd epoch J | real | 4 | -0.9999995e9 | PHYS_ELLIPTICITY | |
| j_2eNum | lasMergeLog | WSA | the extension number of this 2nd epoch J frame | tinyint | 1 | NUMBER | ||
| j_2ErrBits | lasSource, lasSourceRemeasurement | WSA | processing warning/error bitwise flags in 2nd epoch J | int | 4 | -99999999 | CODE_MISC | |
| j_2Eta | lasSource | WSA | Offset of 2nd epoch J detection from master position (+north/-south) | real | 4 | arcsec | -0.9999995e9 | POS_EQ_DEC_OFF |
| When associating individual passband detections into merged sources, a generous (in terms of the positional uncertainties) pairing radius of 2.0 (UKIDSS LAS and GPS; also non-survey programmes) or 1.0 (UKIDSS GPS, DXS and UDS) arcseconds is used, the higher value enabling pairing of moving sources when epoch separations may be several years. Such a large association criterion can of course lead to spurious pairings in the merged sources lists (although note that between passband pairs, handshake pairing is done: both passbands must agree that the candidate pair is their nearest neighbour for the pair to propagate through into the merged source table). In order to help filter spurious pairings out, and assuming that large positional offsets between the different passband detections are not expected (e.g. because of source motion, or larger than usual positional uncertainties) then the attributes Xi and Eta can be used to filter any pairings with suspiciously large offsets in one or more bands. For example, for a clean sample of QSOs from the LAS, you might wish to insist that the offsets in the selected sample are all below 1 arcsecond: simply add WHERE clauses into the SQL sample selection script to exclude all Xi and Eta values larger than the threshold you want. | ||||||||
| j_2Gausig | lasSource, lasSourceRemeasurement | WSA | RMS of axes of ellipse fit in 2nd epoch J | real | 4 | pixels | -0.9999995e9 | MORPH_PARAM |
| j_2HallMag | lasSource | WSA | Total point source 2nd epoch J mag | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| j_2HallMagErr | lasSource | WSA | Error in total point source 2nd epoch J mag | real | 4 | mag | -0.9999995e9 | ERROR |
| j_2Mag | lasSourceRemeasurement | WSA | 2nd epoch J mag (as appropriate for this merged source) | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| j_2MagErr | lasSourceRemeasurement | WSA | Error in 2nd epoch J mag | real | 4 | mag | -0.9999995e9 | ERROR |
| j_2mfID | lasMergeLog | WSA | the UID of the relevant 2nd epoch J multiframe | bigint | 8 | ID_FRAME | ||
| j_2mrat | twomass_scn | 2MASS | J-band average 2nd image moment ratio. | real | 4 | FIT_PARAM_VALUE | ||
| j_2ObjID | lasSource | WSA | the UID of the 2nd epoch J detection | bigint | 8 | -99999999 | ID_NUMBER | |
| j_2ObjID | lasSourceRemeasurement | WSA | the UID of the 2nd epoch J remeasurement | bigint | 8 | -99999999 | ID_NUMBER | |
| j_2PA | lasSource, lasSourceRemeasurement | WSA | ellipse fit celestial orientation in 2nd epoch J | real | 4 | Degrees | -0.9999995e9 | POS_POS-ANG |
| j_2PetroMag | lasSource | WSA | Extended source 2nd epoch J mag (Petrosian) | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| j_2PetroMagErr | lasSource | WSA | Error in extended source 2nd epoch J mag (Petrosian) | real | 4 | mag | -0.9999995e9 | ERROR |
| j_2ppErrBits | lasSource, lasSourceRemeasurement | WSA | additional WFAU post-processing error bits in 2nd epoch J | int | 4 | 0 | CODE_MISC | |
| j_2PsfMag | lasSource | WSA | Point source profile-fitted 2nd epoch J mag | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| j_2PsfMagErr | lasSource | WSA | Error in point source profile-fitted 2nd epoch J mag | real | 4 | mag | -0.9999995e9 | ERROR |
| j_2SeqNum | lasSource | WSA | the running number of the 2nd epoch J detection | int | 4 | -99999999 | ID_NUMBER | |
| j_2SeqNum | lasSourceRemeasurement | WSA | the running number of the 2nd epoch J remeasurement | int | 4 | -99999999 | ID_NUMBER | |
| j_2SerMag2D | lasSource | WSA | Extended source 2nd epoch J mag (profile-fitted) | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| j_2SerMag2DErr | lasSource | WSA | Error in extended source 2nd epoch J mag (profile-fitted) | real | 4 | mag | -0.9999995e9 | ERROR |
| j_2Xi | lasSource | WSA | Offset of 2nd epoch J detection from master position (+east/-west) | real | 4 | arcsec | -0.9999995e9 | POS_EQ_RA_OFF |
| When associating individual passband detections into merged sources, a generous (in terms of the positional uncertainties) pairing radius of 2.0 (UKIDSS LAS and GPS; also non-survey programmes) or 1.0 (UKIDSS GPS, DXS and UDS) arcseconds is used, the higher value enabling pairing of moving sources when epoch separations may be several years. Such a large association criterion can of course lead to spurious pairings in the merged sources lists (although note that between passband pairs, handshake pairing is done: both passbands must agree that the candidate pair is their nearest neighbour for the pair to propagate through into the merged source table). In order to help filter spurious pairings out, and assuming that large positional offsets between the different passband detections are not expected (e.g. because of source motion, or larger than usual positional uncertainties) then the attributes Xi and Eta can be used to filter any pairings with suspiciously large offsets in one or more bands. For example, for a clean sample of QSOs from the LAS, you might wish to insist that the offsets in the selected sample are all below 1 arcsecond: simply add WHERE clauses into the SQL sample selection script to exclude all Xi and Eta values larger than the threshold you want. | ||||||||
| j_5sig_ba | twomass_xsc | 2MASS | J minor/major axis ratio fit to the 5-sigma isophote. | real | 4 | PHYS_AXIS-RATIO | ||
| j_5sig_phi | twomass_xsc | 2MASS | J angle to 5-sigma major axis (E of N). | smallint | 2 | degrees | ERROR | |
| j_5surf | twomass_xsc | 2MASS | J central surface brightness (r<=5). | real | 4 | mag | PHOT_SB_GENERAL | |
| j_ba | twomass_xsc | 2MASS | J minor/major axis ratio fit to the 3-sigma isophote. | real | 4 | PHYS_AXIS-RATIO | ||
| j_back | twomass_xsc | 2MASS | J coadd median background. | real | 4 | CODE_MISC | ||
| j_bisym_chi | twomass_xsc | 2MASS | J bi-symmetric cross-correlation chi. | real | 4 | FIT_PARAM_VALUE | ||
| j_bisym_rat | twomass_xsc | 2MASS | J bi-symmetric flux ratio. | real | 4 | PHOT_FLUX_RATIO | ||
| j_bndg_amp | twomass_xsc | 2MASS | J banding maximum FT amplitude on this side of coadd. | real | 4 | DN | FIT_PARAM_VALUE | |
| j_bndg_per | twomass_xsc | 2MASS | J banding Fourier Transf. period on this side of coadd. | int | 4 | arcsec | FIT_PARAM_VALUE | |
| j_chif_ellf | twomass_xsc | 2MASS | J % chi-fraction for elliptical fit to 3-sig isophote. | real | 4 | FIT_PARAM_VALUE | ||
| j_cmsig | twomass_psc | 2MASS | Corrected photometric uncertainty for the default J-band magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_con_indx | twomass_xsc | 2MASS | J concentration index r_75%/r_25%. | real | 4 | PHYS_CONCENT_INDEX | ||
| j_d_area | twomass_xsc | 2MASS | J 5-sigma to 3-sigma differential area. | smallint | 2 | FIT_RESIDUAL | ||
| j_flg_10 | twomass_xsc | 2MASS | J confusion flag for 10 arcsec circular ap. mag. | smallint | 2 | CODE_MISC | ||
| j_flg_15 | twomass_xsc | 2MASS | J confusion flag for 15 arcsec circular ap. mag. | smallint | 2 | CODE_MISC | ||
| j_flg_20 | twomass_xsc | 2MASS | J confusion flag for 20 arcsec circular ap. mag. | smallint | 2 | CODE_MISC | ||
| j_flg_25 | twomass_xsc | 2MASS | J confusion flag for 25 arcsec circular ap. mag. | smallint | 2 | CODE_MISC | ||
| j_flg_30 | twomass_xsc | 2MASS | J confusion flag for 30 arcsec circular ap. mag. | smallint | 2 | CODE_MISC | ||
| j_flg_40 | twomass_xsc | 2MASS | J confusion flag for 40 arcsec circular ap. mag. | smallint | 2 | CODE_MISC | ||
| j_flg_5 | twomass_xsc | 2MASS | J confusion flag for 5 arcsec circular ap. mag. | smallint | 2 | CODE_MISC | ||
| j_flg_50 | twomass_xsc | 2MASS | J confusion flag for 50 arcsec circular ap. mag. | smallint | 2 | CODE_MISC | ||
| j_flg_60 | twomass_xsc | 2MASS | J confusion flag for 60 arcsec circular ap. mag. | smallint | 2 | CODE_MISC | ||
| j_flg_7 | twomass_xsc | 2MASS | J confusion flag for 7 arcsec circular ap. mag. | smallint | 2 | CODE_MISC | ||
| j_flg_70 | twomass_xsc | 2MASS | J confusion flag for 70 arcsec circular ap. mag. | smallint | 2 | CODE_MISC | ||
| j_flg_c | twomass_xsc | 2MASS | J confusion flag for Kron circular mag. | smallint | 2 | CODE_MISC | ||
| j_flg_e | twomass_xsc | 2MASS | J confusion flag for Kron elliptical mag. | smallint | 2 | CODE_MISC | ||
| j_flg_fc | twomass_xsc | 2MASS | J confusion flag for fiducial Kron circ. mag. | smallint | 2 | CODE_MISC | ||
| j_flg_fe | twomass_xsc | 2MASS | J confusion flag for fiducial Kron ell. mag. | smallint | 2 | CODE_MISC | ||
| j_flg_i20c | twomass_xsc | 2MASS | J confusion flag for 20mag/sq." iso. circ. mag. | smallint | 2 | CODE_MISC | ||
| j_flg_i20e | twomass_xsc | 2MASS | J confusion flag for 20mag/sq." iso. ell. mag. | smallint | 2 | CODE_MISC | ||
| j_flg_i21c | twomass_xsc | 2MASS | J confusion flag for 21mag/sq." iso. circ. mag. | smallint | 2 | CODE_MISC | ||
| j_flg_i21e | twomass_xsc | 2MASS | J confusion flag for 21mag/sq." iso. ell. mag. | smallint | 2 | CODE_MISC | ||
| j_flg_j21fc | twomass_xsc | 2MASS | J confusion flag for 21mag/sq." iso. fid. circ. mag. | smallint | 2 | CODE_MISC | ||
| j_flg_j21fe | twomass_xsc | 2MASS | J confusion flag for 21mag/sq." iso. fid. ell. mag. | smallint | 2 | CODE_MISC | ||
| j_flg_k20fc | twomass_xsc | 2MASS | J confusion flag for 20mag/sq." iso. fid. circ. mag. | smallint | 2 | CODE_MISC | ||
| j_flg_k20fe | twomass_xsc | 2MASS | J confusion flag for 20mag/sq." iso. fid. ell. mag. | smallint | 2 | CODE_MISC | ||
| j_m | twomass_psc | 2MASS | Default J-band magnitude | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_10 | twomass_xsc | 2MASS | J 10 arcsec radius circular aperture magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_15 | twomass_xsc | 2MASS | J 15 arcsec radius circular aperture magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_20 | twomass_xsc | 2MASS | J 20 arcsec radius circular aperture magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_25 | twomass_xsc | 2MASS | J 25 arcsec radius circular aperture magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_30 | twomass_xsc | 2MASS | J 30 arcsec radius circular aperture magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_40 | twomass_xsc | 2MASS | J 40 arcsec radius circular aperture magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_5 | twomass_xsc | 2MASS | J 5 arcsec radius circular aperture magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_50 | twomass_xsc | 2MASS | J 50 arcsec radius circular aperture magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_60 | twomass_xsc | 2MASS | J 60 arcsec radius circular aperture magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_7 | twomass_xsc | 2MASS | J 7 arcsec radius circular aperture magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_70 | twomass_xsc | 2MASS | J 70 arcsec radius circular aperture magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_c | twomass_xsc | 2MASS | J Kron circular aperture magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_e | twomass_xsc | 2MASS | J Kron elliptical aperture magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_ext | twomass_xsc | 2MASS | J mag from fit extrapolation. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_fc | twomass_xsc | 2MASS | J fiducial Kron circular magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_fe | twomass_xsc | 2MASS | J fiducial Kron ell. mag aperture magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_i20c | twomass_xsc | 2MASS | J 20mag/sq." isophotal circular ap. magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_i20e | twomass_xsc | 2MASS | J 20mag/sq." isophotal elliptical ap. magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_i21c | twomass_xsc | 2MASS | J 21mag/sq." isophotal circular ap. magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_i21e | twomass_xsc | 2MASS | J 21mag/sq." isophotal elliptical ap. magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_j21fc | twomass_xsc | 2MASS | J 21mag/sq." isophotal fiducial circ. ap. mag. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_j21fe | twomass_xsc | 2MASS | J 21mag/sq." isophotal fiducial ell. ap. magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_k20fc | twomass_xsc | 2MASS | J 20mag/sq." isophotal fiducial circ. ap. mag. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_k20fe | twomass_xsc | 2MASS | J 20mag/sq." isophotal fiducial ell. ap. magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_stdap | twomass_psc | 2MASS | J-band "standard" aperture magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_m_sys | twomass_xsc | 2MASS | J system photometry magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_mnsurfb_eff | twomass_xsc | 2MASS | J mean surface brightness at the half-light radius. | real | 4 | mag | PHOT_SB_GENERAL | |
| j_msig_10 | twomass_xsc | 2MASS | J 1-sigma uncertainty in 10 arcsec circular ap. mag. | real | 4 | mag | ERROR | |
| j_msig_15 | twomass_xsc | 2MASS | J 1-sigma uncertainty in 15 arcsec circular ap. mag. | real | 4 | mag | ERROR | |
| j_msig_20 | twomass_xsc | 2MASS | J 1-sigma uncertainty in 20 arcsec circular ap. mag. | real | 4 | mag | ERROR | |
| j_msig_25 | twomass_xsc | 2MASS | J 1-sigma uncertainty in 25 arcsec circular ap. mag. | real | 4 | mag | ERROR | |
| j_msig_30 | twomass_xsc | 2MASS | J 1-sigma uncertainty in 30 arcsec circular ap. mag. | real | 4 | mag | ERROR | |
| j_msig_40 | twomass_xsc | 2MASS | J 1-sigma uncertainty in 40 arcsec circular ap. mag. | real | 4 | mag | ERROR | |
| j_msig_5 | twomass_xsc | 2MASS | J 1-sigma uncertainty in 5 arcsec circular ap. mag. | real | 4 | mag | ERROR | |
| j_msig_50 | twomass_xsc | 2MASS | J 1-sigma uncertainty in 50 arcsec circular ap. mag. | real | 4 | mag | ERROR | |
| j_msig_60 | twomass_xsc | 2MASS | J 1-sigma uncertainty in 60 arcsec circular ap. mag. | real | 4 | mag | ERROR | |
| j_msig_7 | twomass_xsc | 2MASS | J 1-sigma uncertainty in 7 arcsec circular ap. mag. | real | 4 | mag | ERROR | |
| j_msig_70 | twomass_xsc | 2MASS | J 1-sigma uncertainty in 70 arcsec circular ap. mag. | real | 4 | mag | ERROR | |
| j_msig_c | twomass_xsc | 2MASS | J 1-sigma uncertainty in Kron circular mag. | real | 4 | mag | ERROR | |
| j_msig_e | twomass_xsc | 2MASS | J 1-sigma uncertainty in Kron elliptical mag. | real | 4 | mag | ERROR | |
| j_msig_ext | twomass_xsc | 2MASS | J 1-sigma uncertainty in mag from fit extrapolation. | real | 4 | mag | ERROR | |
| j_msig_fc | twomass_xsc | 2MASS | J 1-sigma uncertainty in fiducial Kron circ. mag. | real | 4 | mag | ERROR | |
| j_msig_fe | twomass_xsc | 2MASS | J 1-sigma uncertainty in fiducial Kron ell. mag. | real | 4 | mag | ERROR | |
| j_msig_i20c | twomass_xsc | 2MASS | J 1-sigma uncertainty in 20mag/sq." iso. circ. mag. | real | 4 | mag | ERROR | |
| j_msig_i20e | twomass_xsc | 2MASS | J 1-sigma uncertainty in 20mag/sq." iso. ell. mag. | real | 4 | mag | ERROR | |
| j_msig_i21c | twomass_xsc | 2MASS | J 1-sigma uncertainty in 21mag/sq." iso. circ. mag. | real | 4 | mag | ERROR | |
| j_msig_i21e | twomass_xsc | 2MASS | J 1-sigma uncertainty in 21mag/sq." iso. ell. mag. | real | 4 | mag | ERROR | |
| j_msig_j21fc | twomass_xsc | 2MASS | J 1-sigma uncertainty in 21mag/sq." iso.fid.circ.mag. | real | 4 | mag | ERROR | |
| j_msig_j21fe | twomass_xsc | 2MASS | J 1-sigma uncertainty in 21mag/sq." iso.fid.ell.mag. | real | 4 | mag | ERROR | |
| j_msig_k20fc | twomass_xsc | 2MASS | J 1-sigma uncertainty in 20mag/sq." iso.fid.circ. mag. | real | 4 | mag | ERROR | |
| j_msig_k20fe | twomass_xsc | 2MASS | J 1-sigma uncertainty in 20mag/sq." iso.fid.ell.mag. | real | 4 | mag | ERROR | |
| j_msig_stdap | twomass_psc | 2MASS | Uncertainty in the J-band standard aperture magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_msig_sys | twomass_xsc | 2MASS | J 1-sigma uncertainty in system photometry mag. | real | 4 | mag | ERROR | |
| j_msigcom | twomass_psc | 2MASS | Combined, or total photometric uncertainty for the default J-band magnitude. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_msnr10 | twomass_scn | 2MASS | The estimated J-band magnitude at which SNR=10 is achieved for this scan. | real | 4 | mag | SPECT_FLUX_VALUE | |
| j_n_snr10 | twomass_scn | 2MASS | Number of point sources at J-band with SNR>10 (instrumental mag <=15.8) | int | 4 | NUMBER | ||
| j_pchi | twomass_xsc | 2MASS | J chi^2 of fit to rad. profile (LCSB: alpha scale len). | real | 4 | FIT_PARAM_VALUE | ||
| j_peak | twomass_xsc | 2MASS | J peak pixel brightness. | real | 4 | mag | PHOT_SB_GENERAL | |
| j_perc_darea | twomass_xsc | 2MASS | J 5-sigma to 3-sigma percent area change. | smallint | 2 | FIT_PARAM | ||
| j_phi | twomass_xsc | 2MASS | J angle to 3-sigma major axis (E of N). | smallint | 2 | degrees | POS_POS-ANG | |
| j_psfchi | twomass_psc | 2MASS | Reduced chi-squared goodness-of-fit value for the J-band profile-fit photometry made on the 1.3 s "Read_2" exposures. | real | 4 | FIT_PARAM_VALUE | ||
| j_psp | twomass_scn | 2MASS | J-band photometric sensitivity paramater (PSP). | real | 4 | INST_SENSITIVITY | ||
| j_pts_noise | twomass_scn | 2MASS | Base-10 logarithm of the mode of the noise distribution for all point source detections in the scan, where the noise is estimated from the measured J-band photometric errors and is expressed in units of mJy. | real | 4 | INST_NOISE | ||
| j_r_c | twomass_xsc | 2MASS | J Kron circular aperture radius. | real | 4 | arcsec | EXTENSION_RAD | |
| j_r_e | twomass_xsc | 2MASS | J Kron elliptical aperture semi-major axis. | real | 4 | arcsec | EXTENSION_RAD | |
| j_r_eff | twomass_xsc | 2MASS | J half-light (integrated half-flux point) radius. | real | 4 | arcsec | EXTENSION_RAD | |
| j_r_i20c | twomass_xsc | 2MASS | J 20mag/sq." isophotal circular aperture radius. | real | 4 | arcsec | EXTENSION_RAD | |
| j_r_i20e | twomass_xsc | 2MASS | J 20mag/sq." isophotal elliptical ap. semi-major axis. | real | 4 | arcsec | EXTENSION_RAD | |
| j_r_i21c | twomass_xsc | 2MASS | J 21mag/sq." isophotal circular aperture radius. | real | 4 | arcsec | EXTENSION_RAD | |
| j_r_i21e | twomass_xsc | 2MASS | J 21mag/sq." isophotal elliptical ap. semi-major axis. | real | 4 | arcsec | EXTENSION_RAD | |
| j_resid_ann | twomass_xsc | 2MASS | J residual annulus background median. | real | 4 | DN | CODE_MISC | |
| j_sc_1mm | twomass_xsc | 2MASS | J 1st moment (score) (LCSB: super blk 2,4,8 SNR). | real | 4 | CODE_MISC | ||
| j_sc_2mm | twomass_xsc | 2MASS | J 2nd moment (score) (LCSB: SNRMAX - super SNR max). | real | 4 | CODE_MISC | ||
| j_sc_msh | twomass_xsc | 2MASS | J median shape score. | real | 4 | CODE_MISC | ||
| j_sc_mxdn | twomass_xsc | 2MASS | J mxdn (score) (LCSB: BSNR - block/smoothed SNR). | real | 4 | CODE_MISC | ||
| j_sc_r1 | twomass_xsc | 2MASS | J r1 (score). | real | 4 | CODE_MISC | ||
| j_sc_r23 | twomass_xsc | 2MASS | J r23 (score) (LCSB: TSNR - integrated SNR for r=15). | real | 4 | CODE_MISC | ||
| j_sc_sh | twomass_xsc | 2MASS | J shape (score). | real | 4 | CODE_MISC | ||
| j_sc_vint | twomass_xsc | 2MASS | J vint (score). | real | 4 | CODE_MISC | ||
| j_sc_wsh | twomass_xsc | 2MASS | J wsh (score) (LCSB: PSNR - peak raw SNR). | real | 4 | CODE_MISC | ||
| j_seetrack | twomass_xsc | 2MASS | J band seetracking score. | real | 4 | CODE_MISC | ||
| j_sh0 | twomass_xsc | 2MASS | J ridge shape (LCSB: BSNR limit). | real | 4 | FIT_PARAM | ||
| j_shape_avg | twomass_scn | 2MASS | J-band average seeing shape for scan. | real | 4 | INST_SEEING | ||
| j_shape_rms | twomass_scn | 2MASS | RMS-error of J-band average seeing shape. | real | 4 | INST_SEEING | ||
| j_sig_sh0 | twomass_xsc | 2MASS | J ridge shape sigma (LCSB: B2SNR limit). | real | 4 | FIT_PARAM | ||
| j_snr | twomass_psc | 2MASS | J-band "scan" signal-to-noise ratio. | real | 4 | mag | INST_NOISE | |
| j_subst2 | twomass_xsc | 2MASS | J residual background #2 (score). | real | 4 | CODE_MISC | ||
| j_zp_ap | twomass_scn | 2MASS | Photometric zero-point for J-band aperture photometry. | real | 4 | mag | PHOT_ZP | |
| jAperMag3 | dxsSource, gcsSource, gpsSource | WSA | Default point/extended source J aperture corrected mag (2.0 arcsec aperture diameter) If in doubt use this flux estimator |
real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| jAperMag3 | udsSource | WSA | Default point/extended source J mag, no aperture correction applied If in doubt use this flux estimator |
real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| jAperMag3Err | dxsSource, gcsSource, gpsSource, udsSource | WSA | Error in default point/extended source J mag (2.0 arcsec aperture diameter) | real | 4 | mag | -0.9999995e9 | ERROR |
| jAperMag4 | dxsSource, gcsSource, gpsSource | WSA | Extended source J aperture corrected mag (2.8 arcsec aperture diameter) | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| jAperMag4 | udsSource | WSA | Extended source J mag, no aperture correction applied | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| jAperMag4Err | dxsSource, gcsSource, gpsSource, udsSource | WSA | Error in extended source J mag (2.8 arcsec aperture diameter) | real | 4 | mag | -0.9999995e9 | ERROR |
| jAperMag6 | dxsSource, gcsSource, gpsSource | WSA | Extended source J aperture corrected mag (5.7 arcsec aperture diameter) | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| jAperMag6 | udsSource | WSA | Extended source J mag, no aperture correction applied | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| jAperMag6Err | dxsSource, gcsSource, gpsSource, udsSource | WSA | Error in extended source J mag (5.7 arcsec aperture diameter) | real | 4 | mag | -0.9999995e9 | ERROR |
| jClass | dxsSource, dxsSourceRemeasurement, gcsSource, gcsSourceRemeasurement, gpsSource, gpsSourceRemeasurement, udsSource, udsSourceRemeasurement | WSA | discrete image classification flag in J | smallint | 2 | -9999 | CLASS_MISC | |
| jClassStat | dxsSource, dxsSourceRemeasurement, gcsSource, gcsSourceRemeasurement, gpsSource, gpsSourceRemeasurement, udsSourceRemeasurement | WSA | N(0,1) stellarness-of-profile statistic in J | real | 4 | -0.9999995e9 | STAT_PROP | |
| jClassStat | udsSource | WSA | S-Extractor classification statistic in J | real | 4 | -0.9999995e9 | STAT_PROP | |
| jdate | twomass_psc | 2MASS | The Julian Date of the source measurement accurate to +-30 seconds. | float | 8 | Julian days | TIME_DATE | |
| jdate | twomass_scn | 2MASS | Julian Date at beginning of scan. | float | 8 | Julian days | TIME_DATE | |
| jdate | twomass_xsc | 2MASS | Julian date of the source measurement accurate to +-3 minutes. | float | 8 | Julian days | TIME_DATE | |
| jDeblend | dxsSource, dxsSourceRemeasurement, gcsSource, gcsSourceRemeasurement, gpsSource, gpsSourceRemeasurement, udsSource, udsSourceRemeasurement | WSA | flag indicating parent/child relation in J | int | 4 | -99999999 | CODE_MISC | |
| jEll | dxsSource, dxsSourceRemeasurement, gcsSource, gcsSourceRemeasurement, gpsSource, gpsSourceRemeasurement, udsSource, udsSourceRemeasurement | WSA | 1-b/a, where a/b=semi-major/minor axes in J | real | 4 | -0.9999995e9 | PHYS_ELLIPTICITY | |
| jeNum | dxsMergeLog, gcsMergeLog, gpsMergeLog, udsMergeLog | WSA | the extension number of this J frame | tinyint | 1 | NUMBER | ||
| jErrBits | dxsSource, dxsSourceRemeasurement, gcsSource, gcsSourceRemeasurement, gpsSource, gpsSourceRemeasurement, udsSource, udsSourceRemeasurement | WSA | processing warning/error bitwise flags in J | int | 4 | -99999999 | CODE_MISC | |
| jEta | dxsSource, gcsSource, gpsSource, udsSource | WSA | Offset of J detection from master position (+north/-south) | real | 4 | arcsec | -0.9999995e9 | POS_EQ_DEC_OFF |
| When associating individual passband detections into merged sources, a generous (in terms of the positional uncertainties) pairing radius of 2.0 (UKIDSS LAS and GPS; also non-survey programmes) or 1.0 (UKIDSS GPS, DXS and UDS) arcseconds is used, the higher value enabling pairing of moving sources when epoch separations may be several years. Such a large association criterion can of course lead to spurious pairings in the merged sources lists (although note that between passband pairs, handshake pairing is done: both passbands must agree that the candidate pair is their nearest neighbour for the pair to propagate through into the merged source table). In order to help filter spurious pairings out, and assuming that large positional offsets between the different passband detections are not expected (e.g. because of source motion, or larger than usual positional uncertainties) then the attributes Xi and Eta can be used to filter any pairings with suspiciously large offsets in one or more bands. For example, for a clean sample of QSOs from the LAS, you might wish to insist that the offsets in the selected sample are all below 1 arcsecond: simply add WHERE clauses into the SQL sample selection script to exclude all Xi and Eta values larger than the threshold you want. | ||||||||
| jGausig | dxsSource, dxsSourceRemeasurement, gcsSource, gcsSourceRemeasurement, gpsSource, gpsSourceRemeasurement, udsSource, udsSourceRemeasurement | WSA | RMS of axes of ellipse fit in J | real | 4 | pixels | -0.9999995e9 | MORPH_PARAM |
| jHallMag | dxsSource, gcsSource, gpsSource | WSA | Total point source J mag | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| jHallMag | udsSource | WSA | Not available in SE output | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| jHallMagErr | dxsSource, gcsSource, gpsSource | WSA | Error in total point source J mag | real | 4 | mag | -0.9999995e9 | ERROR |
| jHallMagErr | udsSource | WSA | Not available in SE output | real | 4 | mag | -0.9999995e9 | ERROR |
| jitterID | Multiframe | WSA | Serial number in this telescope jitter pattern {image primary HDU keyword: JITTER_I} | smallint | 2 | -9999 | ID_NUMBER | |
| jitterID | Multiframe | WSATransit | Serial number in this telescope jitter pattern {image primary HDU keyword: JITTER_I} | smallint | 2 | -9999 | ID_NUMBER | |
| jitterX | Multiframe | WSA | X (RA) offset in tel jitter pattern {image primary HDU keyword: JITTER_X} | real | 4 | arcsec | -0.9999995e9 | POS_EQ_RA_OFF |
| jitterX | Multiframe | WSATransit | X (RA) offset in tel jitter pattern {image primary HDU keyword: JITTER_X} | real | 4 | arcsec | -0.9999995e9 | POS_EQ_RA_OFF |
| jitterY | Multiframe | WSA | Y (Dec) offset in tel jitter pattern {image primary HDU keyword: JITTER_Y} | real | 4 | arcsec | -0.9999995e9 | POS_EQ_DEC_OFF |
| jitterY | Multiframe | WSATransit | Y (Dec) offset in tel jitter pattern {image primary HDU keyword: JITTER_Y} | real | 4 | arcsec | -0.9999995e9 | POS_EQ_DEC_OFF |
| jMag | CurrentStdStarInfo, PreviousStdStarInfo | WSA | J band total magnitude of star (from external sources if primary) | real | 4 | mag | PHOT_INT-MAG | |
| jMag | dxsSourceRemeasurement, gcsSourceRemeasurement, gpsSourceRemeasurement, udsSourceRemeasurement | WSA | J mag (as appropriate for this merged source) | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| jMagErr | CurrentStdStarInfo, PreviousStdStarInfo | WSA | J band magnitude error of star | real | 4 | mag | ERROR | |
| jMagErr | dxsSourceRemeasurement, gcsSourceRemeasurement, gpsSourceRemeasurement, udsSourceRemeasurement | WSA | Error in J mag | real | 4 | mag | -0.9999995e9 | ERROR |
| jmfID | dxsMergeLog, gcsMergeLog, gpsMergeLog, udsMergeLog | WSA | the UID of the relevant J multiframe | bigint | 8 | ID_FRAME | ||
| jmh | dxsSourceRemeasurement, gcsSourceRemeasurement, gpsSourceRemeasurement, lasSourceRemeasurement, udsSourceRemeasurement | WSA | Default colour J-H (using appropriate mags) | real | 4 | mag | PHOT_COLOR | |
| jmhErr | dxsSourceRemeasurement, gcsSourceRemeasurement, gpsSourceRemeasurement, lasSourceRemeasurement, udsSourceRemeasurement | WSA | Error on colour J-H | real | 4 | mag | ERROR | |
| jmhExt | dxsSource, gcsSource, gpsSource, udsSource | WSA | Extended source colour J-H (using aperMag3) | real | 4 | mag | -0.9999995e9 | PHOT_COLOR |
| Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits. | ||||||||
| jmhExtErr | dxsSource, gcsSource, gpsSource, udsSource | WSA | Error on extended source colour J-H | real | 4 | mag | -0.9999995e9 | ERROR |
| Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits. | ||||||||
| jmhPnt | dxsSource, gcsSource, gpsSource, udsSource | WSA | Point source colour J-H (using aperMag3) | real | 4 | mag | -0.9999995e9 | PHOT_COLOR |
| Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits. | ||||||||
| jmhPntErr | dxsSource, gcsSource, gpsSource, udsSource | WSA | Error on point source colour J-H | real | 4 | mag | -0.9999995e9 | ERROR |
| Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits. | ||||||||
| jmkExt | dxsSource, udsSource | WSA | Extended source colour J-K (using aperMag3) | real | 4 | mag | -0.9999995e9 | PHOT_COLOR |
| Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits. | ||||||||
| jmkExtErr | dxsSource, udsSource | WSA | Error on extended source colour J-K | real | 4 | mag | -0.9999995e9 | ERROR |
| Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits. | ||||||||
| jmkPnt | dxsSource, udsSource | WSA | Point source colour J-K (using aperMag3) | real | 4 | mag | -0.9999995e9 | PHOT_COLOR |
| Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits. | ||||||||
| jmkPntErr | dxsSource, udsSource | WSA | Error on point source colour J-K | real | 4 | mag | -0.9999995e9 | ERROR |
| Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours and extended source colours are computed from the aperture corrected AperMag3 fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands) and generally good signal-to-noise. At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits. | ||||||||
| jObjID | dxsSource, gcsSource, gpsSource, udsSource | WSA | the UID of the J detection | bigint | 8 | -99999999 | ID_NUMBER | |
| jObjID | dxsSourceRemeasurement, gcsSourceRemeasurement, gpsSourceRemeasurement, udsSourceRemeasurement | WSA | the UID of the J remeasurement | bigint | 8 | -99999999 | ID_NUMBER | |
| joinCriterion | RequiredNeighbours | WSA | the join criterion (search radius for matches) | real | 4 | arcminutes | ?? | |
| joinCriterion | RequiredNeighbours | WSATransit | the join criterion (search radius for matches) | real | 4 | arcminutes | ?? | |
| joinType | RequiredNeighbours | WSA | the type of join: 0 (default) or N for special join | smallint | 2 | ?? | ||
| joinType | RequiredNeighbours | WSATransit | the type of join: 0 (default) or N for special join | smallint | 2 | ?? | ||
| jPA | dxsSource, dxsSourceRemeasurement, gcsSource, gcsSourceRemeasurement, gpsSource, gpsSourceRemeasurement, udsSource, udsSourceRemeasurement | WSA | ellipse fit celestial orientation in J | real | 4 | Degrees | -0.9999995e9 | POS_POS-ANG |
| jPetroMag | dxsSource, gcsSource, gpsSource, udsSource | WSA | Extended source J mag (Petrosian) | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| jPetroMagErr | dxsSource, gcsSource, gpsSource, udsSource | WSA | Error in extended source J mag (Petrosian) | real | 4 | mag | -0.9999995e9 | ERROR |
| jppErrBits | dxsSource, dxsSourceRemeasurement, gcsSource, gcsSourceRemeasurement, gpsSource, gpsSourceRemeasurement, udsSource, udsSourceRemeasurement | WSA | additional WFAU post-processing error bits in J | int | 4 | 0 | CODE_MISC | |
| jPsfMag | dxsSource, gcsSource, gpsSource | WSA | Point source profile-fitted J mag | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| jPsfMag | udsSource | WSA | Not available in SE output | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| jPsfMagErr | dxsSource, gcsSource, gpsSource | WSA | Error in point source profile-fitted J mag | real | 4 | mag | -0.9999995e9 | ERROR |
| jPsfMagErr | udsSource | WSA | Not available in SE output | real | 4 | mag | -0.9999995e9 | ERROR |
| jSeqNum | dxsSource, gcsSource, gpsSource, udsSource | WSA | the running number of the J detection | int | 4 | -99999999 | ID_NUMBER | |
| jSeqNum | dxsSourceRemeasurement, gcsSourceRemeasurement, gpsSourceRemeasurement, udsSourceRemeasurement | WSA | the running number of the J remeasurement | int | 4 | -99999999 | ID_NUMBER | |
| jSerMag2D | dxsSource, gcsSource, gpsSource | WSA | Extended source J mag (profile-fitted) | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| jSerMag2D | udsSource | WSA | Not available in SE output | real | 4 | mag | -0.9999995e9 | PHOT_MAG |
| jSerMag2DErr | dxsSource, gcsSource, gpsSource | WSA | Error in extended source J mag (profile-fitted) | real | 4 | mag | -0.9999995e9 | ERROR |
| jSerMag2DErr | udsSource | WSA | Not available in SE output | real | 4 | mag | -0.9999995e9 | ERROR |
| julianDayNum | CurrentNightlyExt | WSATransit | the Julian Day number of the UKIRT night {image primary HDU keyword: UTDATE} | int | 4 | Julian days | TIME_DATE | |
| julianDayNum | CurrentNightlyExt, DetectorSetUp, MultiframeDetector, MultiframeSetUp, PreviousNightlyExt | WSA | the Julian Day number of the UKIRT night {image primary HDU keyword: UTDATE} | int | 4 | Julian days | TIME_DATE | |
| julianDayNum | Multiframe | WSA | the Julian Day number of the UKIRT night | int | 4 | Julian days | TIME_DATE | |
| julianDayNum | Multiframe | WSATransit | the Julian Day number of the UKIRT night | int | 4 | Julian days | TIME_DATE | |
| junkSource | JunkDetection | SSA | Source of junk: 1=satellite track; 2=diffraction spike; 3=bright stellar halo | tinyint | 1 | CLASS_CODE | ||
| jXi | dxsSource, gcsSource, gpsSource, udsSource | WSA | Offset of J detection from master position (+east/-west) | real | 4 | arcsec | -0.9999995e9 | POS_EQ_RA_OFF |
| When associating individual passband detections into merged sources, a generous (in terms of the positional uncertainties) pairing radius of 2.0 (UKIDSS LAS and GPS; also non-survey programmes) or 1.0 (UKIDSS GPS, DXS and UDS) arcseconds is used, the higher value enabling pairing of moving sources when epoch separations may be several years. Such a large association criterion can of course lead to spurious pairings in the merged sources lists (although note that between passband pairs, handshake pairing is done: both passbands must agree that the candidate pair is their nearest neighbour for the pair to propagate through into the merged source table). In order to help filter spurious pairings out, and assuming that large positional offsets between the different passband detections are not expected (e.g. because of source motion, or larger than usual positional uncertainties) then the attributes Xi and Eta can be used to filter any pairings with suspiciously large offsets in one or more bands. For example, for a clean sample of QSOs from the LAS, you might wish to insist that the offsets in the selected sample are all below 1 arcsecond: simply add WHERE clauses into the SQL sample selection script to exclude all Xi and Eta values larger than the threshold you want. | ||||||||