J/ApJ/596/768 Optical depths in 19 QSOs (Schaye+, 2003)
Metallicity of the intergalactic medium using pixel statistics.
II. The distribution of metals as traced by C IV.
Schaye J., Aguirre A., Kim T.-S., Theuns T., Rauch M., Sargent W.L.W.
<Astrophys. J., 596, 768-796 (2003)>
=2003ApJ...596..768S 2003ApJ...596..768S
ADC_Keywords: QSOs ; Redshifts ; Spectra, ultraviolet
Keywords: cosmology: miscellaneous - galaxies: formation -
intergalactic medium - quasars: absorption lines
Abstract:
We measure the distribution of carbon in the intergalactic medium as a
function of redshift z and overdensity δ. Using a hydrodynamical
simulation to link the H I absorption to the density and temperature
of the absorbing gas, and a model for the UV background radiation, we
convert ratios of C IV to H I pixel optical depths into carbon
abundances. For the median metallicity this technique was described
and tested in Paper I (Aguirre et al., 2002ApJ...576....1A 2002ApJ...576....1A) of this
series. Here we generalize it to reconstruct the full probability
distribution of the carbon abundance and apply it to 19 high-quality
quasar absorption spectra.
Description:
We analyzed spectra of the 19 quasars listed in the first column of
Table 1. Fourteen spectra were taken with the UV-Visual Echelle
Spectrograph on the VLT, and five were taken with the High Resolution
Echelle Spectrograph on the Keck telescope. The UVES spectra were
taken from the ESO archive.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 54 19 Observed quasars
table4.dat 117 456 Recovered CIV optical depths
table5.dat 73 42 Observed effective optical depth
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Name QSO name
14- 18 F5.3 --- zem Emission redshift
20- 24 F5.3 --- zmin Minimum absorption redshift
26- 30 F5.3 --- zmed Median absorption redshift
32- 36 F5.3 --- zmax Maximum absorption redshift
38- 44 F7.2 0.1nm Lambdamin Minimum wavelength
46- 50 A5 --- Inst Instrument (UVER or HIRES)
52- 54 A3 --- Ref References (1)
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Note (1): References are numbered as follows:
1 = Kim et al., 2002MNRAS.335..555K 2002MNRAS.335..555K
2 = Kim et al., 2003, MNRAS, submitted (0308103)
3 = Kim et al., 2001, Cat. J/A+A/373/757
4 = Rauch et al., 1997ApJ...481..601R 1997ApJ...481..601R, 1997ApJ...489....7R 1997ApJ...489....7R
5 = Boksenberg et al., 2003, submitted (0307557)
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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- 12 A12 --- Name QSO name
14- 19 F6.3 [---] logtauHI Recovered HI (1216) optical depth (1)
21- 26 F6.3 [---] logtauCIV-0.5 ? 30.85th percentile of the recovered
CIV (1548) optical depth
28 A1 --- n_logtauCIV-0.5 [-] Note (2)
29- 33 F5.3 [---] e_logtauCIV-0.5 ? 1σ error in logtauCIV,-0.5
35- 40 F6.3 [---] logtauCIV ? 50th percentile of the recovered
CIV (1548) optical depth
42 A1 --- n_logtauCIV [-] Note (2)
43- 47 F5.3 [---] e_logtauCIV ? 1σ error in logtauCIV
49- 54 F6.3 [---] logtauCIV+0.5 ? 69.15th percentile of the recovered
CIV (1548) optical depth
56 A1 --- n_logtauCIV+0.5 [-] Note (2)
57- 61 F5.3 [---] e_logtauCIV+0.5 ? 1σ error in logtauCIV,+0.5
63- 68 F6.3 [---] logtauCIV+1.0 ? 84.13th percentile of the recovered
CIV (1548) optical depth
70 A1 --- n_logtauCIV+1.0 [-] Note (2)
71- 75 F5.3 [---] e_logtauCIV+1.0 ? 1σ error in logtauCIV,+1.0
77- 82 F6.3 [---] logtauCIV+1.5 ? 93.32th percentile of the recovered
CIV (1548) optical depth
84 A1 --- n_logtauCIV+1.5 [-] Note (2)
85- 89 F5.3 [---] e_logtauCIV+1.5 ? 1σ error in logtauCIV,+1.5
91- 96 F6.3 [---] logtauCIV+2.0 ? 97.73th percentile of the recovered
CIV (1548) optical depth
98 A1 --- n_logtauCIV+2.0 [-] Note (2)
99-103 F5.3 [---] e_logtauCIV+2.0 ? 1σ error in logtauCIV,+2.0
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Note (1): -9 = indicates that the corresponding tauCIV are the taumin values
(see section 5.1 for the definition of taumin).
Note (2): A '-' indicates that tauHI<tauc
(see section 5.1 for the definition of tauc).
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Name QSO name
15- 19 F5.3 --- zmedA Median absorption redshift, all pixels
21- 25 F5.3 --- zminA Minimum absorption redshift value, all pixels
27- 31 F5.3 --- zmaxA Maximum absorption redshift value, all pixels
33- 37 F5.3 --- taueffA Effective optical depth, all pixels (1)
39- 43 F5.3 --- e_taueffA rms uncertainty on taueffA
45- 49 F5.3 --- zmed Median absorption redshift,
after removal of contamination
51- 55 F5.3 --- zmin Minimum absorption redshift value,
after removal of contamination
57- 61 F5.3 --- zmax Maximum absorption redshift value,
after removal of contamination
63- 67 F5.3 --- taueff Effective optical depth,
after removal of contamination (1)
69- 73 F5.3 --- e_taueff rms uncertainty on taueff
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Note (1): taueff=←lnF>, where F is the normalized flux in the Lyα forest
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History:
From electronic version of the journal
References:
Aguirre et al., Paper I 2002ApJ...576....1A 2002ApJ...576....1A
(End) Greg Schwarz [AAS], Patricia Bauer [CDS] 19-Dec-2003