J/ApJ/708/717 Light curve templates of RR Lyrae stars (Sesar+, 2010)
Light curve templates and Galactic distribution of RR Lyrae stars from Sloan
Digital Sky Survey stripe 82.
Sesar B., Ivezic Z., Grammer S.H., Morgan D.P., Becker A.C., Juric M.,
De Lee N., Annis J., Beers T.C., Fan X., Lupton R.H., Gunn J.E.,
Knapp G.R., Jiang L., Jester S., Johnston D.E., Lampeitl H.
<Astrophys. J., 708, 717-741 (2010)>
=2010ApJ...708..717S 2010ApJ...708..717S
ADC_Keywords: Photometry, SDSS ; Stars, variable ; Stars, halo
Keywords: Galaxy: halo - Galaxy: stellar content - Galaxy: structure -
methods: data analysis - stars: horizontal-branch -
stars: statistics - stars: variables: other
Abstract:
We present an improved analysis of halo substructure traced by RR
Lyrae stars in the Sloan Digital Sky Survey (SDSS) stripe 82 region.
With the addition of SDSS-II data, a revised selection method based on
new ugriz light curve templates results in a sample of 483 RR Lyrae
stars that is essentially free of contamination. The main result from
our first study persists: the spatial distribution of halo stars at
galactocentric distances 5-100kpc is highly inhomogeneous. At least
20% of halo stars within 30kpc from the Galactic center can be
statistically associated with substructure. We present strong direct
evidence, based on both RR Lyrae stars and main-sequence stars, that
the halo stellar number density profile significantly steepens beyond
a Galactocentric distance of ∼30kpc, and a larger fraction of the
stars are associated with substructure. By using a novel method that
simultaneously combines data for RR Lyrae and main-sequence stars, and
using photometric metallicity estimates for main-sequence stars
derived from deep co-added u-band data, we measure the metallicity of
the Sagittarius dSph tidal stream (trailing arm) toward RA∼2h-3h
and DE∼0° to be 0.3dex higher ([Fe/H]=-1.2) than that of
surrounding halo field stars.
Description:
We have combined SDSS-I imaging runs used in Sesar et al.
(2007AJ....134.2236S 2007AJ....134.2236S) with recalibrated SDSS-II SN (Frieman et al.
2008AJ....135..338F 2008AJ....135..338F) imaging runs, and created a catalog with ∼4.4
million unique unresolved (point source) objects. Each object in the
catalog was observed at least four times in the ugr bands. We selected
483 RR Lyrae stars in SDSS stripe 82.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 295 483 Light curve parameters for stripe 82 RR Lyrae stars
table3.dat 115 483 Positions and derived parameters of stripe 82
RR Lyrae stars
phot/* . 483 *Position and ugriz photometry for each star
templ/* . 98 *Individual files for ugriz RR Lyrae template
light curves
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Notes on phot/*: This directory contains positions and ugriz photometry
for 483 stripe 82 RR Lyrae stars. The filenames correspond to RR Lyrae ID
numbers in Tables 2 and 3.
Notes on templ/*: This directory contains ugriz RR Lyrae template light
curves. The number in the filename corresponds to the template ID in
Table 2 and the letter identifies the band.
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See also:
II/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)
J/A+A/526/A28 : SDSS-II supernovae NTT and NOT spectroscopy (Oestman+, 2011)
J/ApJS/186/233 : Variable point sources in SDSS stripe 82. I. (Bhatti+, 2010)
J/AJ/130/1640 : Photometry of candidate RR Lyrae stars in the SDSS (Wu+, 2005)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 7 I7 --- [SIG2010] RR Lyrae identification number
9- 10 A2 --- Type [abc ] RR Lyrae type
12- 25 F14.12 d Per Period
27- 40 F14.12 mag uAmp Best-fit template u band amplitude
42- 56 F15.12 mag umag1 Best-fit template u band maximum brightness (1)
58- 75 F18.12 d T0.u Best-fit template u band epoch of maximum
brightness (MJD)
77- 79 I3 --- Tu Best-fit template u band ID number
81- 94 F14.12 mag gAmp Best-fit template g band amplitude
96-110 F15.12 mag gmag1 Best-fit template g band maximum brightness (1)
112-129 F18.12 d T0.g Best-fit template g band epoch of maximum
brightness (MJD)
131-133 I3 --- Tg Best-fit template g band ID number
135-148 F14.12 mag rAmp Best-fit template r band amplitude
150-164 F15.12 mag rmag1 Best-fit template r band maximum brightness (1)
166-183 F18.12 d T0.r Best-fit template r band epoch of maximum
brightness (MJD)
185-187 I3 --- Tr Best-fit template r band ID number
189-202 F14.12 mag iAmp Best-fit template i band amplitude
204-218 F15.12 mag imag1 Best-fit template i band maximum brightness (1)
220-237 F18.12 d T0.i Best-fit template i band epoch of maximum
brightness (MJD)
239-241 I3 --- Ti Best-fit template i band ID number
243-256 F14.12 mag zAmp Best-fit template z band amplitude
258-272 F15.12 mag zmag1 Best-fit template z band maximum brightness (1)
274-291 F18.12 d T0.z Best-fit template z band epoch of maximum
brightness (MJD)
293-295 I3 --- Tz Best-fit template z band ID number
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Note (1): Corrected for the ISM extinction.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 I7 --- [SIG2010] RR Lyrae identification number
9- 18 F10.6 deg RAdeg Right Ascension in decimal degrees (J2000)
20- 28 F9.6 deg DEdeg Declination in decimal degrees (J2000)
30- 34 F5.3 mag Ar Schlegel et al. 1998ApJ...500..525S 1998ApJ...500..525S ISM
extinction in r band
36- 41 F6.2 kpc Dist Heliocentric distance
43- 48 F6.2 kpc RGC Galactocentric distance
50- 55 F6.3 mag umag Flux-averaged u band magnitude (1)
57- 62 F6.3 mag gmag Flux-averaged g band magnitude (1)
64- 69 F6.3 mag rmag Flux-averaged r band magnitude (1)
71- 76 F6.3 mag imag Flux-averaged i band magnitude (1)
78- 83 F6.3 mag zmag Flux-averaged z band magnitude (1)
85- 90 F6.3 mag Vmag Flux-averaged V band magnitude (1)
92- 96 F5.3 mag u-g Median (u-g) color at minimum brightness (1)
98-102 F5.3 mag e_u-g Uncertainty in u-g
104-109 F6.3 mag g-r Median (g-r) color at minimum brightness (1)
111-115 F5.3 mag e_g-r Uncertainty in g-r
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Note (1): Corrected for ISM extinction.
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Byte-by-byte Description of files: phot/*
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Bytes Format Units Label Explanations
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1- 10 F10.6 deg RAdeg [-51.99/59.25] Right Ascension in decimal
degrees (J2000)
12- 20 F9.6 deg DEdeg Declination in decimal degrees (J2000)
22- 33 F12.6 d JDu Modified Julian date of u band observation
35- 41 F7.3 mag umag ?=-99.99 u band magnitude (1)
43- 49 F7.3 mag e_umag ?=-99 u band magnitude error
51- 62 F12.6 d JDg Modified Julian date of g band observation
64- 70 F7.3 mag gmag ?=-99.99 g band magnitude (1)
72- 78 F7.3 mag e_gmag ?=-99 g band magnitude error
80- 91 F12.6 d JDr Modified Julian date of r band observation
93- 99 F7.3 mag rmag ?=-99.99 r band magnitude (1)
101-107 F7.3 mag e_rmag ?=-99 r band magnitude error
109-120 F12.6 d JDi Modified Julian date of i band observation
122-128 F7.3 mag imag ?=-99.99 i band magnitude (1)
130-136 F7.3 mag e_imag ?=-99 i band magnitude error
138-149 F12.6 d JDz Modified Julian date of z band observation
151-157 F7.3 mag zmag ?=-99.99 z band magnitude (1)
159-165 F7.3 mag e_zmag ?=-99 z band magnitude error
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Note (1): Not corrected for ISM extinction.
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Byte-by-byte Description of files: templ/*
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Bytes Format Units Label Explanations
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1- 5 F5.3 --- phase Template light curve phase
7- 11 F5.3 --- value Template value
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 13-Feb-2012