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J/ApJS/150/19       ChaMP. I. First X-ray source catalog     (Kim+, 2004)

Chandra Multiwavelength Project. I. First X-ray source catalog. 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.Jr, Karovska M., Kashyap V., Maksym P.W., Ratzlaff P.W., Schlegel E.M., Silverman J.D., Tananbaum H.D., Vikhlinin A.A., Wilkes B.J., Grimes J.P. <Astrophys. J. Suppl. Ser., 150, 19 (2004)> =2004ApJS..150...19K
ADC_Keywords: Surveys ; X-ray sources Keywords: surveys - X-rays: general Abstract: The Chandra Multiwavelength Project (ChaMP) is a wide-area (∼14deg2) 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∼10-15 to 10-14erg/s/cm2) ) 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 (∼20counts) 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. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table3.dat 80 19 Source Flags table6.dat 107 102 Energy Conversion Factors table7.dat 84 991 ChaMP X-ray Sources table8.dat 134 991 X-ray Photometry table9.dat 60 991 X-ray colors
Byte-by-byte Description of file: table3.dat
Bytes Format Units Label Explanations
1 A1 --- Type [FXVO] Flag letter (1) 3- 5 I3 --- Flag Flag number 7- 80 A74 --- Com Meaning of the flag
Note (1): Type of source as follows: F = False X-Ray Sources X = X-Ray Sources-Questionable V = Valid Sources, but Source Properties May Be Subject to a Large Uncertainty O = Other Cases
Byte-by-byte Description of file: table6.dat
Bytes Format Units Label Explanations
1- 4 I4 --- ObsID ChaMP X-ray source identification number 6- 8 A3 --- CCDID The CCD identification number (1) 10- 15 F6.2 --- B-1.2 B energy conversion factor for Gamma=1.2 (2) 17- 21 F5.2 --- S-1.2 S energy conversion factor for Gamma=1.2 (2) 23- 28 F6.2 --- H-1.2 H energy conversion factor for Gamma=1.2 (2) 30- 34 F5.2 --- Sc-1.2 Sc energy conversion factor for Gamma=1.2 (2) 36- 41 F6.2 --- Hc-1.2 Hc energy conversion factor for Gamma=1.2 (2) 43- 48 F6.2 --- B-1.4 B energy conversion factor for Gamma=1.4 (2) 50- 54 F5.2 --- S-1.4 S energy conversion factor for Gamma=1.4 (2) 56- 61 F6.2 --- H-1.4 H energy conversion factor for Gamma=1.4 (2) 63- 67 F5.2 --- Sc-1.4 Sc energy conversion factor for Gamma=1.4 (2) 69- 74 F6.2 --- Hc-1.4 Hc energy conversion factor for Gamma=1.4 (2) 76- 81 F6.2 --- B-1.7 B energy conversion factor for Gamma=1.7 (2) 83- 87 F5.2 --- S-1.7 S energy conversion factor for Gamma=1.7 (2) 89- 94 F6.2 --- H-1.7 H energy conversion factor for Gamma=1.7 (2) 96-100 F5.2 --- Sc-1.7 Sc energy conversion factor for Gamma=1.7 (2) 102-107 F6.2 --- Hc-1.7 Hc energy conversion factor for Gamma=1.7 (2)
Note (1): 0-3 for ACIS-I and 4-9 for ACIS-S. Note (2): Energy Conversion Factors (10-13erg/s/cm2 per 1ct/s) are calculated in the following energy bands: B = counts in 0.3-8.0keV and flux in 0.3-8.0keV; S = counts in 0.3-2.5keV and flux in 0.5-2.0keV; H = counts in 2.5-8.0keV and flux in 2.0-8.0keV; Sc = counts in 0.5-2.0keV and flux in 0.5-2.0keV; Hc = counts in 2.0-8.0keV and flux in 2.0-8.0keV.
Byte-by-byte Description of file: table7.dat
Bytes Format Units Label Explanations
1- 5 A5 --- --- [CXOMP] 7- 22 A16 --- CXOMP 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 ePos Positional error (see section 5) 61- 64 F4.1 arcmin Doff The off-axis distance 66- 69 F4.1 arcsec Rad Source extraction radius (see section 3.3) (2) 71- 76 F6.2 ks EExp Effective exposure 78- 80 I3 --- Flag1 ? Source flag (see table3.dat and section 3.5) 82- 84 I3 --- Flag2 ? Source flag (see table3.dat and section 3.5)
Note (1): 0-3 for ACIS-I and 4-9 for ACIS-S Note (2): We choose the source extraction radius to be a 95% encircled energy radius (at 1.5keV) as a function of off-axis angle (determined from the "psfsize" table, psfsize_2000830.fits, available in the CIAO and CALDB public distribution) with a minimum of 3" near the aim point and a maximum of 40" at the far edge of the field of view.
Byte-by-byte Description of file: table8.dat
Bytes Format Units Label Explanations
1- 5 A5 --- --- [CXOMP] 7- 22 A16 --- CXOMP ChaMP source position name in J2000 24- 31 F8.2 ct BNet Net 0.3-8.0keV counts (1) 33- 38 F6.2 ct e_BNet Error in BNet 40- 47 F8.2 ct S1Net Net 0.3-0.9keV counts (1) 49- 54 F6.2 ct e_S1Net Error in S1Net 56- 63 F8.2 ct S2Net Net 0.9-2.5keV counts (1) 65- 70 F6.2 ct e_S2Net Error in S2Net 72- 79 F8.2 ct HNet Net 2.5-8.00keV counts (1) 81- 86 F6.2 ct e_HNet Error in HNet 88- 95 F8.2 ct ScNet Net 0.5-2.0keV counts (1) 97-102 F6.2 ct e_ScNet Error in ScNet 104-111 F8.2 ct HcNet Net 2.0-8.0keV counts (1) 113-118 F6.2 ct e_HcNet Error in HcNet 120-126 F7.3 10-16W/m2 BFlux The 0.3-8.0keV flux in units of 10-13erg/s/cm2 (1) 128-133 F6.3 10-16W/m2 e_BFlux Error in BFlux
Note (1): Source counts were extracted within a circle centered on the wavdetect-determined source position and background counts are extracted locally in an annulus surrounding the source. See section 3.3 for more details.
Byte-by-byte Description of file: table9.dat
Bytes Format Units Label Explanations
1- 5 A5 --- --- [CXOMP] 7- 22 A16 --- CXOMP ChaMP source position name in J2000 24- 28 F5.2 --- HR The Hardness Ratio, (H-S)/(H+S) (1) 30- 33 F4.2 --- e_HR Error in HR 35- 40 F6.2 --- C21 The C21 (log(S1/S2)) X-ray color (1) (2) 42- 46 F5.2 --- e_C21 Error in C21 48- 53 F6.2 --- C32 The C32 (log(S2/H)) X-ray color (1) (2) 55- 59 F5.2 --- e_C32 Error in C32
Note (1): Where H is the total count in the hard (2.5-8.0keV) band, S is the total count in the soft (0.3-2.5keV) band, S1 is the total count in the 0.3-0.9keV band, S2 is the total count in the 0.9-2.5keV band. Note (2): Note on X-ray colors as follows: -99.00 = lower limit 99.00 = upper limit 999.00 = undetermined
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 23-Jan-2004
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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