J/MNRAS/401/2715 CIV column densities in z<2.5 QSOs (D'odorico+, 2010)
The rise of the C IV mass density at z < 2.5.
D'Odorico V., Calura F., Cristiani S., Viel M.
<Mon. Not. R. Astron. Soc., 401, 2715-2721 (2010)>
=2010MNRAS.401.2715D 2010MNRAS.401.2715D
ADC_Keywords: QSOs ; Redshifts ; Spectroscopy
Keywords: intergalactic medium - quasars: absorption lines -
cosmology: observations
Abstract:
The cosmic evolution of the metal content of the intergalactic medium
puts stringent constraints on the properties of galactic outflows and
on the nature of UV background. In this paper, we present a new
measure of the redshift evolution of the mass density of CIV,
{OMEGA}CIV, in the interval 1.5~<z~<4 based on a sample of more than
1500 CIV lines with column densities 1012~<N(CIV)~<1015cm-2.
This sample more than doubles the absorption redshift path covered in
the range z<2.5 by previous samples. The result shows a significant
increase of {OMEGA}CIV towards the lower redshifts at variance with
the previously pictured constant behaviour.
Description:
The core of our sample is formed by the high-resolution, high S/N QSO
spectra already described in Saitta et al. (2008MNRAS.385..519S 2008MNRAS.385..519S) and
D'Odorico et al. (2008MNRAS.389.1727D 2008MNRAS.389.1727D). Most of them were obtained
with the Ultraviolet and Visual Echelle Spectrograph (UVES)
spectrograph at the Kueyen unit of the European Southern Observatory
(ESO) VLT (Cerro Paranal, Chile) in the framework of the ESO Large
Programme (LP): 'The Cosmic Evolution of the IGM' (Bergeron et al.,
2004Msngr.118...40B 2004Msngr.118...40B).
In this work, three more QSOs were added to that sample, mainly to
increase the redshift extension above z∼3. UVES spectra of the QSOs,
Q0055-269, PKS 2000-330 and PKS 1937-101, were downloaded from
the ESO Archive and reduced with the UVES pipeline following the
standard procedure. The continuum level was determined by
interpolating with a cubic spline of the region of the spectrum free
from evident absorption features.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
sources.dat 39 25 List of studied QSOs
table2.dat 49 1107 CIV absorption lines
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See also:
J/A+A/283/759 : CIV QSO absorption systems (Petitjean+ 1994)
J/A+A/473/791 : CIV absorption in DLAs and sub-DLAs systems (Fox+, 2007)
J/ApJ/641/78 : CIV variability in 105 SDSS quasars (Wilhite+, 2006)
J/ApJ/666/757 : CIV(1549Å emission line in AGNs (Sulentic+, 2007)
Byte-by-byte Description of file: sources.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name QSO name
13- 14 I2 h RAh Simbad Right ascension (J2000)
16- 17 I2 min RAm Simbad Right ascension (J2000)
19- 22 F4.1 s RAs Simbad Right ascension (J2000)
24 A1 --- DE- Simbad Declination sign (J2000)
25- 26 I2 deg DEd Simbad Declination (J2000)
28- 29 I2 arcmin DEm Simbad Declination (J2000)
31- 32 I2 arcsec DEs Simbad Declination (J2000)
34- 39 F6.4 --- zem Emission redshift (from original table2)
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Byte-by-byte Description of file:table2.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name QSO name
13- 21 F9.7 --- z Redshift
23- 29 F7.3 km/s b Doppler parameter, b
30 A1 --- n_b [a] a when no error on b
32- 36 F5.3 km/s e_b ? rms uncertainty on b
38- 43 F6.3 [cm-2] logN(CIV) CIV column density
45- 49 F5.3 [cm-2] e_logN(CIV) rms uncertainty on logN(CIV)
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 01-Jun-2010