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J/ApJS/165/19       SEXSI catalog. III                       (Eckart+, 2006)

The Serendipitous Extragalactic X-ray Source Identification (SEXSI) program. III. Optical spectroscopy. Eckart M.E., Stern D., Helfand D.J., Harrison F.A., Mao P.H., Yost S.A. <Astrophys. J. Suppl. Ser., 165, 19-56 (2006)> =2006ApJS..165...19E
ADC_Keywords: Surveys ; X-ray sources ; Redshifts ; Photometry Keywords: catalogs - galaxies: active - surveys - X-rays: diffuse background - X-rays: galaxies - X-rays: galaxies: clusters - X-rays: general Abstract: We present the catalog of 477 spectra from the Serendipitous Extragalactic X-ray Source Identification (SEXSI) program, a survey designed to probe the dominant contributors to the 2-10keV cosmic X-ray background. Our survey covers 1deg2 of sky to 2-10keV fluxes of 1x10-14ergs/cm2/s, and 2deg2 for fluxes of 3x10-14ergs/cm2/s. Our spectra reach to R-band magnitudes of ~<24 and have produced identifications and redshifts for 438 hard X-ray sources. Description: The SEXSI survey is designed to obtain optical identifications for a large sample of hard (2-10keV) X-ray sources detected in extragalactic Chandra fields in the flux range 10-13 to 10-15ergs/cm2/s. Paper I (Harrison et al., 2003, Cat. J/ApJ/596/944) provides details of the X-ray source extraction and analysis. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table2.dat 134 477 SEXSI Optical Spectroscopy Catalog notes.dat 80 26 Spectral notes
See also: J/ApJ/596/944 : SEXSI catalog. I (Harrison+, 2003) J/ApJS/156/35 : SEXSI catalog. II (Eckart+, 2005) Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 16 A16 --- CXOSEXSI The IAU-registered name (JHHMMSS.s+DDMMSS) 18- 19 I2 h RAh Hour of Right Ascension (J2000) (1) 21- 22 I2 min RAm Minute of Right Ascension (J2000) (1) 24- 28 F5.2 s RAs Second of Right Ascension (J2000) (1) 30 A1 --- DE- Sign of the Declination (J2000) (1) 31- 32 I2 deg DEd Degree of Declination (J2000) (1) 34- 35 I2 arcmin DEm Arcminute of Declination (J2000) (1) 37- 40 F4.1 arcsec DEs Arcsecond of Declination (J2000) (1) 42- 46 F5.2 arcmin OAA Off-axis angle 48- 54 F7.2 aW/m2 HFlux Galactic extinction corrected hard band (2.0-10keV) flux (in 10-15erg/cm2/s) 56 I1 --- f_HR [0/1] Flag on HR, 1 for lower limit (2) 58- 62 F5.2 --- HR Hardness ratio (3) 64 I1 --- Opt [0/6] Optical ID flag (4) 66- 70 F5.2 mag Rcmag ? The Cousins R band magnitude 72- 75 F4.1 mag RmagLim ? Limiting R Magnitude of Image 77- 81 F5.2 [-] FX/opt ? Log of the X-ray-to-optical flux ratio 83- 87 F5.3 --- z ? Redshift 89- 93 A5 --- Class ? Object type (5) 95- 97 A3 --- Notes ? Spectral footnotes, in notes.dat file 99-102 F4.1 [10-7W] LX ? Log of the hard band (2.0-10keV) luminosity in erg/s (6) 104-105 A2 --- f_nH ? Unsecure nH value (7) 107-110 F4.1 [cm-2] nH ? Log of best-fit n_H_ from spectral fit (8) 112 A1 --- f_nH.lo ? Unsecure nHlo value (7) 113-116 F4.1 [cm-2] nH.lo ? One sigma low value of log10(nH) (8) 118 A1 --- f_nH.hi ? Unsecure nHhi value (7) 119-122 F4.1 --- nH.hi ? One sigma high value of log10(nH) (8) 124-128 I5 0.1nm wl.lo ? Lower spectrum wavelength range (9) 130-134 I5 0.1nm wl.hi ? Higher spectrum wavelength range (9)
Note (1): X-ray positions are corrected for average X-ray to optical offset (to correct Chandra astrometry). Note (2): Hardness ratio flag as follows: 1 = hardness ratio is a lower limit 0 = hardness ratio is measurement (not a limit) Note (3): HR=(H-S)/(H+S) where H is the corrected counts in the 2.0-10keV band and S is the corrected counts in the 0.5-2.0keV band. See Section 5 for details. Note (4): Optical ID flag as follows: 6 = non-detection but near bright source (limiting mag will be incorrect) 5 = unclear which source is optical counterpart 4 = near bright source (magnitude affected) 3 = bright source - magnitude taken from Guide Star Catalog II 2 = Upper Limit 1 = optical identification 0 = no optical coverage Note (5): Object type as follows: ALG = absorption-line galaxy ELG = emission-line galaxy BLAGN = broad-lined AGN NLAGN = narrow-line AGN star = any type of star (see Section 5 for class definitions) Note (6): For this calculation, we assume the source has an X-ray spectral index Γ=1.4, and use the cosmology Ωm=0.3, Ωλ=0.7, h=0.65 to calculate the luminosity distance. Note (7): Flag as follows: S = Source detected on off-axis ACIS-S chip (2-3) and thus nH is calculated from HR, not spectral fit. See Section 5. < = When a nH measurement is zero we report '<' in the corresponding flag column. > = nH is a lower limit (occurs when HR is a lower limit and nH derived from HR). H = Bad XSPEC fit. nH is calculated from HR, not spectral fit. Note (8): These columns present the logarithm of the best-fit nH value, as well as 1σ low and 1σ high values from the fit. When a nH measurement is zero we report '<' in the flag column. Note (9): Shifted to the rest frame and in units of Angstroms. Sources with no z/class (only continuum detected) have the wavelength range reported in the observed frame.
Byte-by-byte Description of file: notes.dat
Bytes Format Units Label Explanations
1 A1 --- Note Note code 3- 80 A78 --- Text Text of the note
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 14-Dec-2007
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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