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Title: The evolution of the Si  iv content in the Universe from the epoch of reionization to cosmic noon
ABSTRACT

We investigate the abundance and distribution of metals in the high-redshift intergalactic medium and circum-galactic medium through the analysis of a sample of almost 600 Si iv absorption lines detected in high- and intermediate-resolution spectra of 147 quasars. The evolution of the number density of Si iv lines, the column density distribution function, and the cosmic mass density are studied in the redshift interval 1.7 ≲ z ≲ 6.2 and for log N(Si iv) ≥ 12.5. All quantities show a rapid increase between z ∼ 6 and z ≲ 5 and then an almost constant behaviour to z ∼ 2 in very good agreement with what is already observed for C iv absorption lines. The present results are challenging for numerical simulations: When simulations reproduce our Si iv results, they tend to underpredict the properties of C iv, and when the properties of C iv are reproduced, the number of strong Si iv lines [log N(Si iv) > 14] is overpredicted.

 
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Award ID(s):
2006550 1751404
NSF-PAR ID:
10364669
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Oxford University Press
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
512
Issue:
2
ISSN:
0035-8711
Format(s):
Medium: X Size: p. 2389-2401
Size(s):
["p. 2389-2401"]
Sponsoring Org:
National Science Foundation
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