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J/ApJS/188/473        Chandra variable guide star catalog       (Nichols+, 2010)

The Chandra Variable Guide Star Catalog. Nichols J.S., Henden A.A., Huenemoerder D.P., Lauer J.L., Martin E., Morgan D.L., Sundheim B.A. <Astrophys. J. Suppl. Ser., 188, 473-487 (2010)> =2010ApJS..188..473N
ADC_Keywords: Stars, variable ; Surveys ; X-ray sources Keywords: catalogs - methods: observational - space vehicles: instruments - stars: statistics - stars: variables: general Abstract: Variable stars have been identified among the optical-wavelength light curves of guide stars used for pointing control of the Chandra X-ray Observatory. We present a catalog of these variable stars along with their light curves and ancillary data. Variability was detected to a lower limit of 0.02mag amplitude in the 4000-10000Å range using the photometrically stable Aspect Camera on board the Chandra spacecraft. The Chandra Variable Guide Star Catalog (VGUIDE) contains 827 stars, of which 586 are classified as definitely variable and 241 are identified as possibly variable. Of the 586 definite variable stars, we believe 319 are new variable star identifications. Types of variables in the catalog include eclipsing binaries, pulsating stars, and rotating stars. The variability was detected during the course of normal verification of each Chandra pointing and results from analysis of over 75000 guide star light curves from the Chandra mission. The VGUIDE catalog represents data from only about 9 years of the Chandra mission. Also, guide stars were often used multiple times for Chandra observations, so many of the stars in the VGUIDE catalog have multiple light curves available from various times in the mission. The catalog is presented as both online data associated with this paper and as a public Web interface. The stars available for use as Chandra guide stars are generally 6-11mag and are commonly spectral types A and later. Statistics of variability compared to spectral type indicate the expected dominance of A-F stars as pulsators. Eclipsing binaries are consistently 20%-30% of the detected variables across all spectral types. Description: Identifications are based on examinations of the light curves of the guide stars for observations taken between 2000 January 29 and 2009 May 17. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table4.dat 203 827 The VGuide catalog
See also: B/gcvs : General Catalogue of Variable Stars (Samus+ 2007-2010) : Chandra VGuide home page Byte-by-byte Description of file: table4.dat
Bytes Format Units Label Explanations
1- 10 I10 --- AGASCID Chandra Guide Star Catalog (AGASC) ID 12- 29 A18 --- SIMBAD Simbad star name 31- 32 I2 h RAh AGASC Hour of Right Ascension (J2000) 34- 35 I2 min RAm AGASC Minute of Right Ascension (J2000) 37- 41 F5.2 s RAs AGASC Second of Right Ascension (J2000) 43- 53 F11.7 deg RAdeg AGASC Right Ascension in decimal degrees (J2000) 55 A1 --- DE- AGASC Sign of the Declination (J2000) 56- 57 I2 deg DEd AGASC Degree of Declination (J2000) 59- 60 I2 arcmin DEm AGASC Arcminute of Declination (J2000) 62- 65 F4.1 arcsec DEs AGASC Arcsecond of Declination (J2000) 67- 77 F11.7 deg DEdeg AGASC Declination in decimal degrees (J2000) 79-112 A34 --- OType Simbad long object type 114-123 A10 --- SpType Simbad spectral type 125-127 A3 --- otyp Simbad star short type (defined in OType) 129-141 A13 --- Var Variability Category (1) 143-154 A12 --- Vclass Variability Classification (as defined in B/gcvs) 156-166 F11.3 d Epoch ? Epoch of Variability 168-177 F10.6 d Period ? Period of Variability 179 A1 --- UV [Y/N] Ultra-Violet Source 181 A1 --- X [Y/N] X-Ray Source 183 A1 --- IR [Y/N] Infra-Red Source 185-187 I3 --- Num Number of Chandra observations (2) 189-192 I4 ks Exp Total Chandra observation time (2) 194 A1 --- Kn [Y/N] Previously Known Variable 196-203 A8 --- Status VGuide Status of Star (suspect or accepted)
Note (1): Seven categories defined as cataclysmic, eclipsing, eruptive, multiple, pulsating, rotating or indeterminate Note (2): Using this guide star.
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 29-Jul-2010
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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