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 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:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 88 204 List of Archival Sources
table4.dat 82 174 X-ray and UV Parameters
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See also:
B/chandra : The Chandra Archive Log (CXC, 1999-)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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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)
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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 2002ApJ...565...50C)
3 = Peroux et al. (2001AJ....121.1799P 2001AJ....121.1799P)
4 = Anderson et al. (2001, cat. J/AJ/122/503)
5 = Kennefick et al. (1995AJ....110...78K 1995AJ....110...78K)
6 = Storrie-Lombardi et al. (1996ApJ...468..121S 1996ApJ...468..121S)
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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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)
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Note (1): Inferred from COLDEN (Dickey & Lockman, 1990ARA&A..28..215D 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.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 06-Jan-2009