J/AJ/130/1640 Photometry of candidate RR Lyrae stars in the SDSS (Wu+, 2005) ================================================================================ CCD photometry of candidate RR Lyrae stars in the Sloan Digital Sky Survey. Wu C., Qiu Y.L., Deng J.S., Hu J.Y., Zhao Y.H. =2005AJ....130.1640W ================================================================================ ADC_Keywords: Stars, variable ; Photometry, CCD Keywords: Galaxy: halo - Galaxy: structure - stars: variables: other Abstract: We present unfiltered CCD photometry of a sample of 71 candidate RR Lyrae stars during 2003 and 2004, out of 148 candidate stars that were selected from Sloan Digital Sky Survey (SDSS) commissioning data by Ivezic and coworkers (2000AJ....120..963I). We obtain light curves of 69 candidate stars and present a catalog of their positions, amplitudes, periods, types, and mean magnitudes. We confirm that the 69 stars are true RR Lyrae variables based on periods and light curves, for the first time for 41 of them. We identify 57 type ab, 11 type c, and 1 type d (double-mode) in our sample. The double-mode RR Lyrae star shows properties similar to globular cluster stars and are unlike field stars of the Galactic halo in the Petersen diagram. Description: Our CCD images were obtained without a filter using two telescope systems, the 0.6 and 0.8m telescopes at the Xinglong station of the National Astronomical Observatory of China (NAOC) during 2003 and 2004. File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file table1.dat 73 70 RR Lyrae stars (one with two different modes) -------------------------------------------------------------------------------- See also: J/PASP/109/524 : Light Curves for 40 RR Lyraes (Layden 1997) J/ApJ/542/257 : MACHO LMC first-overtone RR Lyrae (Alcock+, 2000) J/AJ/127/1158 : QUEST RR Lyrae Survey first catalog (Vivas+, 2004) http://www.sdss.org : SDSS Home Page Byte-by-byte Description of file: table1.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 3 I3 --- [IGF2000] Running RR Lyrae identification number (1) 5- 6 I2 h RAh Hour of Right Ascension (J2000) 8- 9 I2 min RAm Minute of Right Ascension (J2000) 11- 15 F5.2 s RAs Second of Right Ascension (J2000) 17 A1 --- DE- Sign of the Declination (J2000) 18- 19 I2 deg DEd Degree of Declination (J2000) 21- 22 I2 arcmin DEm Arcminute of Declination (J2000) 24- 27 F4.1 arcsec DEs Arcsecond of Declination (J2000) 29- 30 I2 --- o_r'amp Number of light curve observations of ID 32- 35 F4.2 mag r'amp r' amplitude 37- 44 F8.6 d Per Period 46- 57 F12.4 d HJD Heliocentric Julian date at maximum light 59- 60 A2 --- Type RR Lyrae type 62- 66 F5.2 mag r'mag Mean SDSS r' band magnitude 68- 71 F4.2 mag e_r'mag Error in r'mag 73 A1 --- n_[IGF2000] [q] Indicates ID identified by Vivas et al. (2004, Cat. ) -------------------------------------------------------------------------------- Note (1): Star 91 is a RRd with fundamental mode (amplitude=0.46, period=0.354260) and secondary mode (amplitude=0.25,period=0.474188). -------------------------------------------------------------------------------- History: From electronic version of the journal ================================================================================ (End) Greg Schwarz [AAS], Marianne Brouty [CDS] 16-Feb-2006