Less and more IGM-transmitted galaxies from z ∼ 2.7 to z ∼ 6 from VANDELS and VUDS
Abstract
Aims: Our aim is to analyze the variance of the intergalactic medium (IGM) transmission by studying this parameter in the rest-frame UV spectra of a large sample of high-redshift galaxies.
Methods: We made use of the VIMOS Ultra Deep Survey and the VANDELS public survey to gain insight into the far UV spectrum of 2.7 < z < 6 galaxies. Using the SPARTAN fitting software, we estimated the IGM toward individual galaxies and then divided them into two sub-samples characterized by a transmission above or below the theoretical prescription. We created average spectra of combined VUDS and VANDELS data for each set of galaxies in seven redshift bins.
Results: The resulting spectra clearly exhibit the variance of the IGM transmission that can be seen directly from high-redshift galaxy observations. Computing the optical depth based on the IGM transmission, we find an excellent agreement with results for quasi-stellar objects. In addition, our measurements appear to suggest that there is a large dispersion of redshift where a complete Gunn-Peterson Trough occurs, depending on the line of sight.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- June 2021
- DOI:
- 10.1051/0004-6361/202038438
- arXiv:
- arXiv:2103.02946
- Bibcode:
- 2021A&A...650A..63T
- Keywords:
-
- intergalactic medium;
- galaxies: high-redshift;
- cosmology: miscellaneous;
- Astrophysics - Cosmology and Nongalactic Astrophysics;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- Accepted for publication on A&