J/MNRAS/491/129 The GTC OSIRIS broad-band DR1 (Cortes-Contreras+, 2020)
The Gran Telescopio Canarias OSIRIS broad-band first data release.
Cortes-Contreras M., Bouy H., Solano E., Mahlke M., Jimenez-Esteban F.,
Alacid J.M., Rodrigo C.
<Mon. Not. R. Astron. Soc., 491, 129-152 (2020)>
=2020MNRAS.491..129C 2020MNRAS.491..129C (SIMBAD/NED BibCode)
ADC_Keywords: Photometry, SDSS ; Photometry, Kron ; Fundamental catalog ;
Stars, dwarfs ; Effective temperatures
Keywords: techniques: image processing - catalogues - virtual observatory tools
Abstract:
We present the first release of GTC OSIRIS broad-band data archive.
This is an effort conducted in the framework of the Spanish Virtual
Observatory to help optimize science from the Gran Telescopio Canarias
Archive. Data Release 1 includes 6788 broad-band images in the Sloan
griz filters obtained between 2009 April and 2014 January and the
associated catalogue with roughly 6.23 million detections of more than
630000 unique sources. The catalogue contains standard PSF and Kron
aperture photometry with a mean accuracy better than 0.09 and 0.15mag,
respectively. The relative astrometric residuals are always better
than 30mas and better than 15mas in most cases. The absolute
astrometric uncertainty of the catalogue is of 0.12arcsec. In this
paper we describe the procedure followed to build the image archive
and the associated catalogue, as well as the quality tests carried out
for validation. To illustrate some of the scientific potential of the
catalogue, we also provide two examples of its scientific
exploitation: discovery and identification of asteroids and cool
dwarfs.
Description:
We obtain 27470 raw broad-band images from the GTC Public Archive
acquired between 2009 April and 2014 January in the griz bands. A
total of 5638 among them were obtained using windowing (moving target
images) and were discarded for the present release. The vast majority
of them were targeting a few transiting targets requiring a high
temporal frequency, and the loss in spatial coverage is minimum. Thus,
it is important to remark that the absence of a source in the
catalogue does not imply the absence of GTC OSIRIS observations in
that position of the sky.
A significant number (13230) of early images were missing the standard
MJD-OBS keyword giving the precise acquisition date, which is crucial
for many studies focusing on the time-domain. Although it is possible
to recover the missing information through other non-standard FITS
keywords (e.g. OPENTIME), we will focus in this first data release on
the 8602 (27470-5638-13230) images with the standard MJD-OBS keyword.
Among them, there are 858 calibration images that will not be included
in the catalogue. Hence, we process 7744 OSIRIS images in the griz
filters.
In this first release, the data base includes 6788 images in the Sloan
griz bands with exposure times ranging from 0.5 to 900s, and 6226520
entries in the catalogue corresponding to 633559 astronomical sources.
The catalogue is astrometrically and photometrically calibrated in
standard PSF and automatic (Kron equivalent) photometry using 2MASS,
SDSS DR10, or USNO-B1 for the astrometry and Pan-STARRS DR1 for the
photometry, allowing a broad range of scientific activities.
Table C1 lists the OSIRIS and Gaia DR2 identifiers and effective
temperatures of the 49 dwarf candidates and the identifiers of the
late-type binary components.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
gtcdet.dat 1185 6226520 Detection catalogue
gtcsrc.dat 2335 633559 Source catalogue
tablec1.dat 69 51 OSIRIS and Gaia DR2 identifiers, and effective
temperatures of the 49 cool dwarf candidates
--------------------------------------------------------------------------------
Byte-by-byte Description of file: gtcdet.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 21 F21.17 deg RAdeg Right ascension (J2000)
23- 43 F21.19 arcsec e_RAdeg Error on RAdeg
45- 65 F21.17 deg DEdeg Declination (J2000)
67- 85 F19.17 arcsec e_DEdeg Error on DEdeg
87- 124 A38 --- ID Unique source identifier
(GTC-OSIRIS-BBI-DR1-JHHMMSS.ss+DDMMSS.s)
126- 167 A42 --- IDdet Detection identifier composed by the ID
of the source and '_n', where n is an
integer going from 1 to the total number
of detections of the source
169- 261 A93 --- imurl URL access to the FITS image in which the
detection has been made
263- 366 A104 --- GTC Link to GTC archive
368- 373 F6.3 mag gmag ? PSF calibrated g-band magnitude
375- 379 F5.3 mag e_gmag ? Error on gmag
381- 386 F6.3 mag rmag ? PSF calibrated r-band magnitude
388- 392 F5.3 mag e_rmag ? Error on rmag
394- 399 F6.3 mag imag ? PSF calibrated i-band magnitude
401- 405 F5.3 mag e_imag ? Error on imag
407- 412 F6.3 mag zmag ? PSF calibrated z-band magnitude
414- 418 F5.3 mag e_zmag ? Error on zmag
420 A1 --- fpsf [ABC] Flag for PSF calibrated
magnitude (G1)
422- 427 F6.3 mag gmagauto ? AUTO calibrated g-band magnitude
429- 433 F5.3 mag e_gmagauto ? Error on gmagauto
435- 440 F6.3 mag rmagauto ? AUTO calibrated r-band magnitude
442- 446 F5.3 mag e_rmagauto ? Error on rmagauto
448- 453 F6.3 mag imagauto ? AUTO calibrated i-band magnitude
455- 459 F5.3 mag e_imagauto ? Error on imagauto
461- 466 F6.3 mag zmagauto ? AUTO calibrated z-band magnitude
468- 472 F5.3 mag e_zmagauto ? Error on zmagauto
474 A1 --- fauto [ABC] Flag for AUTO calibrated
magnitude (G2)
476- 486 F11.7 mag gmagap1 ? g-band aperture photometry for
aperture 1 (1)
488- 498 F11.7 mag gmagap2 ? g-band aperture photometry for
aperture 2 (1)
500- 510 F11.7 mag gmagap3 ? g-band aperture photometry for
aperture 3 (1)
512- 523 E12.7 mag e_gmagap1 ? Error on gmagap1
525- 536 E12.7 mag e_gmagap2 ? Error on gmagap2
538- 549 E12.7 mag e_gmagap3 ? Error on gmagap3
551- 561 F11.7 mag gmagmod ? g-band model photometry
563- 575 E13.8 mag e_gmagmod ? Error on gmagmod
577- 596 F20.16 mag rmagap1 ? r-band aperture photometry for
aperture 1 (1)
598- 617 F20.16 mag rmagap2 ? r-band aperture photometry for
aperture 2 (1)
619- 638 F20.16 mag rmagap3 ? r-band aperture photometry for
aperture 3 (1)
640- 660 E21.16 mag e_rmagap1 ? Error on rmagap1
662- 682 E21.16 mag e_rmagap2 ? Error on rmagap2
684- 704 E21.16 mag e_rmagap3 ? Error on rmagap3
706- 725 F20.16 mag rmagmod ? r-band model photometry
727- 748 E22.17 mag e_rmagmod ? Error on rmagmod
750- 769 F20.16 mag imagap1 ? i-band aperture photometry for
aperture 1 (1)
771- 790 F20.16 mag imagap2 ? i-band aperture photometry for
aperture 2 (1)
792- 811 F20.16 mag imagap3 ? i-band aperture photometry for
aperture 3 (1)
813- 833 E21.16 mag e_imagap1 ? Error on imagap1
835- 855 E21.16 mag e_imagap2 ? Error on imagap2
857- 877 E21.16 mag e_imagap3 ? Error on imagap3
879- 898 F20.16 mag imagmod ? i-band model photometry
900- 921 E22.17 mag e_imagmod ? Error on imagmod
923- 942 F20.16 mag zmagap1 ? z-band aperture photometry for
aperture 1 (1)
944- 963 F20.16 mag zmagap2 ? z-band aperture photometry for
aperture 2 (1)
965- 984 F20.16 mag zmagap3 ? z-band aperture photometry for
aperture 3 (1)
986-1006 E21.16 mag e_zmagap1 ? Error on zmagap1
1008-1028 E21.16 mag e_zmagap2 ? Error on zmagap2
1030-1050 E21.16 mag e_zmagap3 ? Error on zmagap3
1052-1071 F20.16 mag zmagmod ? z-band model photometry
1073-1094 E22.17 mag e_zmagmod ? Error on zmagmod
1096-1104 F9.7 --- elong Elongation of the detection defined as A/B
1106-1118 E13.8 --- ellip ? Ellipticity of the detection defined as
1-B/A
1120-1137 F18.16 arcsec FWHM ? Full width half maximum of the detection
1139-1150 F12.7 --- SNR ? Signal to noise ratio
1152-1169 F18.12 d MJD ? Modified Julian Date of the observation
1171-1172 A2 --- Type [E/E*/P/P*/ ] Flag indicating whether the
detection is point-like (P or P*) or
extense (E or E*) (2)
1174 A1 --- f_ID [ps] Inicates if it is a primary (p) or
secondary (s) detection, as defined in
Section 7.1.3
1176-1185 F10.8 --- cl ? Point-like coefficient (G3)
--------------------------------------------------------------------------------
Note (1): Three fixed apertures were used:
- 21, 31, and 41 pixels in 1x1 binning mode, corresponding to 2.66,
3.94, and 5.21arcsec, respectively
- 11, 15, and 21 pixels in 2x2 binning mode, corresponding to 2.79,
3.81, and 5.33arcsec, respectively
Note (2): See Section 7.1.2 of the article for details
--------------------------------------------------------------------------------
Byte-by-byte Description of file: gtcsrc.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 38 A38 --- ID Unique source identifier
(GTC-OSIRIS-BBI-DR1-JHHMMSS.ss+DDMMSS.s)
40- 60 F21.17 deg RAdeg Right ascension (J2000)
62- 82 F21.19 arcsec e_RAdeg Error on RAdeg
84- 104 F21.17 deg DEdeg Declination (J2000)
106- 124 F19.17 arcsec e_DEdeg Error on DEdeg
126- 135 F10.8 --- cl ? Point-like coefficient (G3)
137- 178 A42 --- IDdetg Detection identifier of the PSF
photometry in the g-band (1)
180- 272 A93 --- imurlg URL access to the FITS image in which
the PSF detection in the g-band has
been made
274- 377 A104 --- GTCg Link to GTC archive for the observations
in the g-band
379- 384 F6.3 mag gmag ? PSF calibrated g-band magnitude
386- 390 F5.3 mag e_gmag ? Error on gmag
392 A1 --- f_gmag [ABC] Flag on gmag (G1)
394- 411 F18.12 d MJDgpsf ? Modified Julian Date of the observation
of the PSF photometry in the g-band
413- 454 A42 --- IDdetgauto Detection identifier of the AUTO
photometry in the g-band (1)
456- 548 A93 --- imurlgauto URL access to the FITS image in which
the AUTO detection in the g-band has
been made
550- 653 A104 --- GTCgauto Link to GTC archive for the observations
in the g-band
655- 660 F6.3 mag gmagauto ? AUTO calibrated g-band magnitude
662- 666 F5.3 mag e_gmagauto ? Error on gmagauto
668 A1 --- f_gmagauto [ABC] Flag on gmagauto (G2)
670- 687 F18.12 d MJDgauto ? Modified Julian Date of the observation
of the AUTO photometry in the g-band
689- 730 A42 --- IDdetr Detection identifier of the PSF
photometry in the r-band (1)
732- 824 A93 --- imurlr URL access to the FITS image in which the
PSF detection in the r-band has been
made
826- 928 A103 --- GTCr Link to GTC archive for the observations
in the r-band
930- 935 F6.3 mag rmag ? PSF calibrated r-band magnitude
937- 941 F5.3 mag e_rmag ? Error on rmag
943 A1 --- f_rmag [ABC] Flag on rmag (G1)
945- 962 F18.12 d MJDrpsf ? Modified Julian Date of the observation
of the PSF photometry in the r-band
964-1005 A42 --- IDdetrauto Detection identifier of the AUTO
photometry in the r-band (1)
1007-1099 A93 --- imurlrauto URL access to the FITS image in which the
AUTO detection in the r-band has been
made
1101-1203 A103 --- GTCrauto Link to GTC archive for the observations
in the r-band
1205-1210 F6.3 mag rmagauto ? AUTO calibrated r-band magnitude
1212-1216 F5.3 mag e_rmagauto ? Error on rmagauto
1218 A1 --- f_rmagauto [ABC] Flag on rmagauto (G2)
1220-1237 F18.12 d MJDrauto ? Modified Julian Date of the observation
of the AUTO photometry in the r-band
1239-1280 A42 --- IDdeti Detection identifier of the PSF
photometry in the i-band (1)
1282-1374 A93 --- imurli URL access to the FITS image in which the
PSF detection in the i-band has been
made
1376-1477 A102 --- GTCi Link to GTC archive for the observations
in the i-band
1479-1484 F6.3 mag imag ? PSF calibrated i-band magnitude
1486-1490 F5.3 mag e_imag ? Error on imag
1492 A1 --- f_imag [ABC] Flag on imag (G1)
1494-1511 F18.12 d MJDipsf ? Modified Julian Date of the observation
of the PSF photometry in the i-band
1513-1554 A42 --- IDdetiauto Detection identifier of the AUTO
photometry in the i-band (1)
1556-1648 A93 --- imurliauto URL access to the FITS image in which the
AUTO detection in the i-band has been
made
1650-1751 A102 --- GTCiauto Link to GTC archive for the observations
in the i-band
1753-1758 F6.3 mag imagauto ? AUTO calibrated i-band magnitude
1760-1764 F5.3 mag e_imagauto ? Error on imagauto
1766 A1 --- f_imagauto [ABC] Flag on imagauto (G2)
1768-1785 F18.12 d MJDiauto ? Modified Julian Date of the observation
of the AUTO photometry in the i-band
1787-1828 A42 --- IDdetz Detection identifier of the PSF
photometry in the z-band (1)
1830-1922 A93 --- imurlz URL access to the FITS image in which the
PSF detection in the z-band has been
made
1924-2026 A103 --- GTCz Link to GTC archive for the observations
in the z-band
2028-2033 F6.3 mag zmag ? PSF calibrated z-band magnitude
2035-2039 F5.3 mag e_zmag ? Error on zmag
2041 A1 --- f_zmag [ABC] Flag on zmag (G1)
2043-2060 F18.12 d MJDzpsf ? Modified Julian Date of the
observation of the PSF photometry in
the z-band
2062-2103 A42 --- IDdetzauto Detection identifier of the AUTO
photometry in the z-band (1)
2105-2197 A93 --- imurlzauto URL access to the FITS image in which the
AUTO detection in the z-band has been
made
2199-2301 A103 --- GTCzauto Link to GTC archive for the observations
in the z-band
2303-2308 F6.3 mag zmagauto ? AUTO calibrated z-band magnitude
2310-2314 F5.3 mag e_zmagauto ? Error on zmagauto
2316 A1 --- f_zmagauto [ABC] Flag on zmagauto (G2)
2318-2335 F18.12 d MJDzauto ? Modified Julian Date of the
observation of the AUTO photometry in
the z-band
--------------------------------------------------------------------------------
Note (1): Identifier composed by the ID of the source and '_n', where n is an
integer going from 1 to the total number of detections of the source
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablec1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 38 A38 --- ID Unique source identifier
(GTC-OSIRIS-BBI-DR1-JHHMMSS.ss+DDMMSS.s)
40- 42 A3 --- f_ID [*/**/***/ ] Flag on ID (1)
44- 62 I19 --- GaiaDR2 Gaia DR2 source identifier
64- 69 F6.1 K Teff ? Effective temperature
--------------------------------------------------------------------------------
Note (1): Flag as follows:
* = Secondary component of the close K+M binary system
** = Primary component of the late-type binary
*** = Secondary component of the late-type binary
--------------------------------------------------------------------------------
Global Notes:
Note (G1): Flag as follows:
A = PSF calibrated magnitudes within the interval of magnitudes used for
the photometric calibration
B = PSF calibrated magnitudes fainter than the faintest magnitude used for
the photometric calibration
C = PSF calibrated magnitudes brighter than the brightest magnitude used for
the photometric calibration
Note (G2): Flag as follows:
A = AUTO calibrated magnitudes within the interval of magnitudes used for
the photometric calibration
B = AUTO calibrated magnitudes fainter than the faintest magnitude used for
the photometric calibration
C = AUTO calibrated magnitudes brighter than the brightest magnitude used
for the photometric calibration
Note (G3): cl is defined as the ratio between number of point-like (P or P*)
detections and the total number of point-like and extense (E or E*)
classifications of the same source (NP/(NP+NE). cl equal to 1
indicates that the source has been always classified as point-like,
and cl equal to 0 indicates that the source has been always
classified as extense.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 08-Feb-2023