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: http://www.sao.ru/cats/doc/CHANDRA_MP.html
Дата изменения: Wed Mar 18 12:25:11 2015 Дата индексирования: Sun Apr 10 04:15:51 2016 Кодировка: Поисковые слова: extreme ultraviolet |
Chandra Multiwavelength Project. I. First X-Ray Source Catalog Abstract The Chandra Multiwavelength Project (ChaMP) is a wide-area (~14 deg2) survey of serendipitous Chandra X-ray sources, aiming to establish fair statistical samples covering a wide range of characteristics (such as absorbed active galactic nuclei, high-z clusters of galaxies) at flux levels (fX~10-15to10-14 ergs s-1 cm-2) intermediate between the Chandra deep surveys and previous missions. We present the first ChaMP catalog, which consists of 991 near on-axis, bright X-ray sources obtained from the initial sample of 62 observations. The data have been uniformly reduced and analyzed with techniques specifically developed for the ChaMP and then validated by visual examination. To assess source reliability and positional uncertainty, we perform a series of simulations and also use Chandra data to complement the simulation study. The false source detection rate is found to be as good as or better than expected for a given limiting threshold. On the other hand, the chance of missing a real source is rather complex, depending on the source counts, off-axis distance (or PSF), and background rate. The positional error (95% confidence level) is usually less than 1" for a bright source, regardless of its off-axis distance, while it can be as large as 4" for a weak source (~20 counts) at a large off-axis distance (Doff-axis>8'). We have also developed new methods to find spatially extended or temporary variable sources, and those sources are listed in the catalog. Title: Chandra Multi-wavelength Project (ChaMP). I. First X-ray Source Catalog Authors: Kim D.-W., Cameron R.A., Drake J.J., Evans N.R., Freeman P., Gaetz T.J., Ghosh H., Green P.J., Harnden F.R., Karovska M., Kashyap P.W., Maksym P.W., Ratzlaff P.W., Schlegel E.M., Silverman J.D., Tananbaum A.A., Vikhlinin A.A., Wilkes B.J. Table: ChaMP X-ray Sources ================================================================================ Byte-by-byte Description of file: datafile7.txt -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 22 A22 --- Name ChaMP source position name in J2000 24- 27 I4 --- ObsID ChaMP X-ray source identification number 29 I1 --- CCDID The CCD identification number (1) 31- 33 I3 --- SNum Source number assigned by wavdetect 35- 44 F10.6 deg RAdeg Right Ascension in decimal degrees (J2000) 46- 55 F10.6 deg DEdeg Declination in decimal degrees (J2000) 57- 59 F3.1 arcsec Error Positional error (see section 5) 61- 64 F4.1 arcmin Doff The off-axis distance 66- 69 F4.1 arcsec Rad The 95% EE source extraction radius (see section 3.3) 71- 76 F6.2 ks EExp Effective exposure 78- 84 A7 --- SrcFlag Source flag (see Table 3 and section 3.5) -------------------------------------------------------------------------------- CXOMP J001758.9+163119 520 2 20 4.495466 16.522075 2.2 8.2 17.1 59.01