V/141 Light-Motion Curve Catalogue (LMCC) in Stripe 82 (Bramich+ 2008)
The Light-Motion Curve Catalogue in SDSS Stripe 82 (LMCC)
Bramich D.M., Vidrih S., Wyrzykowski L., Munn J.A., Lin H., Evans N.W.,
Smith M.C., Belokurov V., Gilmore G., Zucker D.B., Hewett P.C.,
Watkins L.L., Faria D.C., Fellhauer M., Miknaitis G., Bizyaev D., Ivezic Z.,
Schneider D.P., Snedden S.A., Malanushenko E., Malanushenko V., Pan K.
<Mon. Not. R. Astron. Soc. 386, 887 (2008)>
=2008MNRAS.386..887B 2008MNRAS.386..887B
=2013yCat.5141....0B 2013yCat.5141....0B
ADC_Keywords: Positional data ; Proper motions ; Photometry, ugriz ;
Stars, variable
Keywords: catalogues ; stars: photometry, astrometry, variables ;
Galaxy: stellar content ; galaxies: photometry
Abstract:
We present a public archive of light-motion curves in Sloan Digital
Sky Survey (SDSS) Stripe 82, covering 99° in right ascension
(20.7h to 3.3h) and spanning 2.52° in declination (-1.26 to 1.26),
for a total sky area of about 249sq.deg. Stripe 82 has been repeatedly
monitored in the u, g, r, i and z bands over a seven-year baseline.
Objects are cross-matched between runs, taking into account the
effects of any proper motion. The resulting catalogue contains almost
4million light-motion curves of stellar objects and galaxies. The
photometry are recalibrated to correct for varying photometric
zeropoints, achieving ∼20mmag and 30mmag root-mean-square (RMS)
accuracy down to 18mag in the g, r, i and z bands for point sources
and extended sources, respectively. The astrometry are recalibrated
to correct for inherent systematic errors in the SDSS astrometric
solutions, achieving 32mas and 35mas RMS accuracy down to 18mag for
point sources and extended sources, respectively.
For each light-motion curve, 229 photometric and astrometric
quantities are derived and stored in a higher-level catalogue. On the
photometric side, these include mean exponential and PSF magnitudes
along with uncertainties, RMS scatter, χ2 per degree of freedom,
various magnitude distribution percentiles, object type (stellar or
galaxy), and eclipse, Stetson and Vidrih variability indices. On the
astrometric side, these quantities include mean positions, proper
motions as well as their uncertainties and χ2 per degree of
freedom. The here presented light-motion curve catalogue is complete
down to r∼21.5mag and is at present the deepest large-area photometric
and astrometric variability catalogue available.
Description:
The full LMCC catalogue consists of 396 FITS files in the "lmcc"
subdirectory, each of these files containing the astrometric and
photometric results for the sources in 1 minute of right ascension.
The higher-level catalogue consists of 8 FITS files in the "hlc"
subdirectory, each containing the 229 photometric and astrometric
quantities for the sources in 1 hour of right ascension.
The 8 files "hlc_xx.dat" (xx representing the hour of right ascension)
represent a "slim" version of the full catalogue, and contain 36 of
the 229 parameters for each of the 3,700,548 sources.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
hlc_00.dat 303 446842 High-level "slim" catalogue, RA=00:00-01:00
hlc_01.dat 303 426892 High-level "slim" catalogue, RA=01:00-02:00
hlc_02.dat 303 442984 High-level "slim" catalogue, RA=02:00-03:00
hlc_03.dat 303 128785 High-level "slim" catalogue, RA=03:00-03:18
hlc_20.dat 303 390491 High-level "slim" catalogue, RA=20:42-21:00
hlc_21.dat 303 844981 High-level "slim" catalogue, RA=21:00-22:00
hlc_22.dat 303 549637 High-level "slim" catalogue, RA=22:00-23:00
hlc_23.dat 303 469936 High-level "slim" catalogue, RA=23:00-24:00
hlc/* . 8 Full FITS version of Higher-level catalogue
lmcc/* . 396 Full Light-Motion Curve Catalog, FITS files
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See also:
http://das.sdss.org/value_added/stripe_82_variability/SDSS_82_public :
SDSS-Stripe82 LMCC page
Byte-by-byte Description of file: hlc_*.dat
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Bytes Format Units Label Explanations
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1- 21 A21 --- Name Light curve name (LC_NAME)
24- 33 F10.2 d t0 [2451075/2456710] Weighted mean heliocentric
Julian date (T0)
35- 41 F7.2 d dt Time span of the light-motion curve (TIME_SPAN)
44- 45 I2 --- Nep [1/85] Number of good positional measurements
(NPOSEPOCHS)
47- 49 F3.1 --- Ot [3/6] Mean object type (MEANOBJECTTYPE) (3)
51- 61 F11.7 deg RAdeg Weighted mean of the RA measurements (ICRS)
(RA_MEAN)
63- 73 F11.7 deg DEdeg Weighted mean of the Dec measurements (ICRS)
(DEC_MEAN)
75- 77 I3 mas e_RAdeg [3/78] Uncertainty on RAdeg (RAMEANERR)
79- 81 I3 mas e_DEdeg [3/78] Uncertainty on DEdeg (DECMEANERR)
83- 90 E8.2 --- chi2RA ?=- χ2 of RA for a model with a proper
motion (RACHISQLIN)
92- 99 E8.2 --- chi2DE ?=- χ2 of Declination for a model with
a proper motion (DECCHISQLIN)
101-109 F9.1 mas/yr pmRA ?=- Proper motion along RA (RA_PM) (1)
111-116 F6.1 mas/yr e_pmRA ?=- Uncertainty on pmRA (RAPMERR)
118-126 F9.1 mas/yr pmDE ?=- Proper motion along Declination (DEC_PM)
128-133 F6.1 mas/yr e_pmDE ?=- Uncertainty on pmDE (DECPMERR)
136-137 I2 --- Nu [0/66] Number of good u-band photometric
data points (NGOODEPOCHS)
139-144 F6.3 mag umag ?=- Weighted mean SDSS u-band magnitude (2)
146-151 F6.3 mag e_umag ?=- Uncertainty on umag
153-158 F6.3 mag s_umag ?=- Root-mean-square deviation of umag
160-167 E8.2 --- uchi2 ?=- Chi-squared of umag
170-171 I2 --- Ng [0/84] Number of good g-band photometric
data points (NGOODEPOCHS)
173-178 F6.3 mag gmag ?=- Weighted mean SDSS g-band magnitude (2)
180-185 F6.3 mag e_gmag ?=- Uncertainty on gmag
187-192 F6.3 mag s_gmag ?=- Root-mean-square deviation of gmag
194-201 E8.2 --- gchi2 ?=- Chi-squared of gmag
204-205 I2 --- Nr [0/84] Number of good r-band photometric
data points (NGOODEPOCHS)
207-212 F6.3 mag rmag ?=- Weighted mean SDSS r-band magnitude (2)
214-219 F6.3 mag e_rmag ?=- Uncertainty on rmag
221-226 F6.3 mag s_rmag ?=- Root-mean-square deviation of rmag
228-235 E8.2 --- rchi2 ?=- Chi-squared of rmag
238-239 I2 --- Ni [0/85] Number of good i-band photometric
data points (NGOODEPOCHS)
241-246 F6.3 mag imag ?=- Weighted mean SDSS i-band magnitude (2)
248-253 F6.3 mag e_imag ?=- Uncertainty on imag
255-260 F6.3 mag s_imag ?=- Root-mean-square deviation of imag
262-269 E8.2 --- ichi2 ?=- Chi-squared of imag
272-273 I2 --- Nz [0/85] Number of good z-band photometric
data points (NGOODEPOCHS)
275-280 F6.3 mag zmag ?=- Weighted mean SDSS z-band magnitude (2)
282-287 F6.3 mag e_zmag ?=- Uncertainty on zmag
289-294 F6.3 mag s_zmag ?=- Root-mean-square deviation of zmag
296-303 E8.2 --- zchi2 ?=- Chi-squared of zmag
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Note (1): Computed only when dt≥1.5 days
Note (2): PSF magnitude (MEAN_PSFMAG) for point sources (Ot≥4.5),
or exponential magnitude (MEAN_EXPMAG) for extended objects (Ot<4.5).
Note (3): the value is the averaged types from the various observations,
between 3.0=galaxy and 6.0=stellar
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History:
* 07-Oct-2013: The FITS files were prepared by D. Bramich;
creation of the files hlc_*.dat from the FITS files at CDS,
unfortunately with the wrong magnitude (MEAN_PSFMAG for extended
sources and MEAN_EXPMAG for point sources)
* 20-Mar-2014: correction of magnitudes (use MEAN_EXPMAG for extended
sources and MEAN_PSFMAG for point sources)
(End) Francois Ochsenbein [CDS] 07-Oct-2013