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J/ApJ/657/116    X-ray and UV parameters of radio-quiet quasars  (Kelly+, 2007)

Evolution of the X-ray emission of radio-quiet quasars. Kelly B.C., Bechtold J. <Astrophys. J. 657, 116 (2007)> =2007ApJ...657..116K
ADC_Keywords: QSOs ; X-ray sources ; Redshifts Keywords: accretion, accretion disks - quasars: general - ultraviolet: galaxies - X-rays: galaxies Abstract: We report new Chandra observations of seven optically faint, z∼4 radio-quiet quasars (RQQs). We have combined these new observations with previous Chandra observations of RQQs to create a sample of 174 sources. These sources have 0.1<z<4.7, and 1044ergs/s<νLν(2500Å)<1048ergs/s. The X-ray detection fraction is 90%. Description: The new observations targeted seven non-BAL (broad absorption line) RQQs with z>4 from the literature. These were known to be among the faintest [νLν(2500Å)~<3x1046ergs/s] z∼4 optically selected quasars to be targeted thus far by Chandra or XMM-Newton. All seven were observed on-axis on the ACIS-S3 chip with exposure times 10-23ks. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table2.dat 88 204 List of Archival Sources table4.dat 82 174 X-ray and UV Parameters
See also: B/chandra : The Chandra Archive Log (CXC, 1999-) Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 9 A9 --- Name Source identification (HHMM+DDMM, J2000, QSO JHHMM+DDMM in Simbad) 11- 12 I2 h RAh Hour of Right Ascension (J2000) 14- 15 I2 min RAm Minute of Right Ascension (J2000) 17- 20 F4.1 s RAs Second of Right Ascension (J2000) 22 A1 --- DE- Sign of the Declination (J2000) 23- 24 I2 deg DEd Degree of Declination (J2000) 26- 27 I2 arcmin DEm Arcminute of Declination (J2000) 29- 32 F4.1 arcsec DEs Arcsecond of Declination (J2000) 34- 38 F5.3 --- z Redshift 40- 44 F5.2 mag rmag The r-band apparent magnitude 46- 49 I4 --- OBSID Observation identification number 51- 55 F5.2 arcmin theta Off-axis angle 57- 62 F6.1 ct Cts Number of observed background-subtracted 0.3-7.0keV source counts (1) 64- 69 F6.1 ks ExpTime Exposure time (1) 71 A1 --- l_FX Limit flag on FX 73- 79 F7.3 10-17W/m2 FX Unabsorbed 2-10 keV flux (2) 81- 84 F4.2 10-17W/m2 e_FX ? Uncertainty in FX (2) 86 I1 --- r_z Observed frame optical spectrum reference (3) 88 I1 --- r_rmag Reference for rmag (3)
Note (1): For sources with multiple observation IDs, the reported counts and exposure time are summed over the observation IDs. Note (2): Assuming a power-law. A photon index of ΓX=1.9 was assumed for those sources with <50 counts. In units of 10-14erg/cm2/s. Note (3): References as follows: 1 = SDSS, Cat. II/282 2 = Constantin et al. (2002ApJ...565...50C) 3 = Peroux et al. (2001AJ....121.1799P) 4 = Anderson et al. (2001, cat. J/AJ/122/503) 5 = Kennefick et al. (1995AJ....110...78K) 6 = Storrie-Lombardi et al. (1996ApJ...468..121S)
Byte-by-byte Description of file: table4.dat
Bytes Format Units Label Explanations
1- 9 A9 --- Name Source name (HHMM+DDMM, J2000) 11 A1 --- New [e] e: One of seven new Chandra observations 13- 17 F5.3 --- z Redshift 19- 22 F4.2 10+20cm-2 NH Galactic Hydrogen column density (1) 24 A1 --- l_n0 Limit flag on n0 25- 30 F6.2 10-6cm-2/s/keV n0 Normalization value at 1keV (2) 32- 36 F5.2 10-6cm-2/s/keV E_n0 ? Upper 1σ error in n0 38- 42 F5.2 10-6cm-2/s/keV e_n0 ? Lower 1σ error in n0 44- 47 F4.2 --- Gamma ? Photon index (3) 49- 52 F4.2 --- E_Gamma ? Upper 1σ error in Gamma 54- 57 F4.2 --- e_Gamma ? Lower 1σ error in Gamma 59- 63 F5.2 10-7W logL2500 Log of the 2500Å luminosity (4) 65 A1 --- l_logL2keV Limit flag on logL2keV 66- 70 F5.2 10-7W logL2keV Log of the 2keV luminosity (4) 72 A1 --- l_a-ox Limit flag on a-ox 73- 76 F4.2 --- a-ox The X-ray to UV/optical flux ratio 78- 82 F5.2 --- a-UV ? The UV spectral slope (5)
Note (1): Inferred from COLDEN (Dickey & Lockman, 1990ARA&A..28..215D). Note (2): When fitting n0 for the sources with <50 counts, we fix Gamma=1.9. Note (3): The photon index could not be estimated for those sources with upper limits. Note (4): In units of erg/s. Note (5): The UV spectral slope could not be estimated for sources with z<0.5.
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 06-Jan-2009
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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