Circum-Galactic Medium in the Halo of Quasars

Frontiers in Astronomy and Space Sciences

Falomo, Renato¹  Scarpa, Riccardo¹  Kotilainen, Jari K.²  Ottolina, Riccardo²  Treves, Aldo⁵  Farina, Emanuele Paolo⁵  Uslenghi, Michela⁸ 

[1] degli Studi dell'Dipartimento di Scienza e Alta Tecnologia (DISAT), UniversitàFinnish Centre for Astronomy with ESO (FINCA), University of Turku, Finland;Instituto de Astrofisica de Canarias, Spain;Insubria, Italy;Istituto di Astrofisica Spaziale e Fisica Cosmica di Milano (INAF), Italy;Max-Planck-Institut füOsservatorio Astronomico di Padova (INAF), Italy;r Astronomie, Germany

关键词: quasar;    quasar pair;    quasar environment;    Quasar spectra;    galaxy around quasar;   

DOI  :  10.3389/fspas.2017.00061

学科分类：空间科学

来源: Frontiers

【 摘 要 】

The properties of circum-galactic gas in the halo of quasar host galaxies are investigated analyzing Mg II 2800 and C IV 1540 absorption-line systems along the line of sight close to quasars. We use optical spectroscopy of closely aligned pairs of quasars (projected distance ≤ 200 kpc, but at very different redshift) obtained at the VLT and Gran Telescopio Canarias to investigate the distribution of the absorbing gas for a sample of quasars at z∼1. Absorption ̊ associated with the foreground quasars are revealed up to 200 kpc systems of EW ≥ 0.3 A from the centre of the host galaxy, showing that the structure of the absorbing gas is patchy with a covering fraction quickly decreasing beyond 100 kpc. We used optical and near-IR images obtained at VLT to investigate the relations between the properties of the circum-galactic medium of the host galaxies and of the large scale galaxy environments of the foreground quasars.

【 授权许可】

CC BY