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 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:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 134 477 SEXSI Optical Spectroscopy Catalog
notes.dat 80 26 Spectral notes
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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
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Bytes Format Units Label Explanations
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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 nH from spectral fit (8)
112 A1 --- f_nH.lo ? Unsecure nHlo value (7)
113-116 F4.1 [cm-2] nH.lo ? One σ low value of log10(nH) (8)
118 A1 --- f_nH.hi ? Unsecure nHhi value (7)
119-122 F4.1 --- nH.hi ? One σ 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)
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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.
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Byte-by-byte Description of file: notes.dat
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Bytes Format Units Label Explanations
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1 A1 --- Note Note code
3- 80 A78 --- Text Text of the note
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 14-Dec-2007