Chemical abundances of the damped Lyman α systems in the XQ-100 survey

Berg, T. A. M.T. A. M.BergEllison, S. L.S. L.EllisonSánchez-Ramírez, R.R.Sánchez-RamírezProchaska, J. X.J. X.ProchaskaLopez, S.S.LopezD'ODORICO, ValentinaValentinaD'ODORICOBecker, G.G.BeckerChristensen, L.L.ChristensenCUPANI, GuidoGuidoCUPANIDenney, K.K.DenneyWorseck, G.G.Worseck2020-05-192020-05-1920160035-8711http://hdl.handle.net/20.500.12386/24980The XQ-100 survey has provided high signal-noise spectra of 100 redshift 3-4.5 quasars with the X-Shooter spectrograph. The metal abundances for 13 elements in the 41 damped Ly α systems (DLAs) identified in the XQ-100 sample are presented, and an investigation into abundances of a variety of DLA classes is conducted. The XQ-100 DLA sample contains five DLAs within 5000 km s-1 of their host quasar (proximate DLAs; PDLAs) as well as three sightlines which contain two DLAs within 10 000 km s-1 of each other along the same line of sight (multiple DLAs; MDLAs). Combined with previous observations in the literature, we demonstrate that PDLAs with log N(H I) < 21.0 show lower [S/H] and [Fe/H] [relative to intervening systems with similar redshift and N(H I)], whilst higher [S/H] and [Si/H] are seen in PDLAs with log N(H I) > 21.0. These abundance discrepancies are independent of their line-of-sight velocity separation from the host quasar, and the velocity width of the metal lines (v90). Contrary to previous studies, MDLAs show no difference in [α/Fe] relative to single DLAs matched in metallicity and redshift. In addition, we present follow-up UVES data of J0034+1639, a sightline containing three DLAs, including a metal-poor DLA with [Fe/H] = -2.82 (the third lowest [Fe/H] in DLAs identified to date) at zabs = 4.25. Lastly we study the dust-corrected [Zn/Fe], emphasizing that near-IR coverage of X-Shooter provides unprecedented access to Mg II, Ca II and Ti II lines (at redshifts 3-4) to provide additional evidence for subsolar [Zn/Fe] ratio in DLAs.STAMPAenChemical abundances of the damped Lyman α systems in the XQ-100 surveyArticle10.1093/mnras/stw22322-s2.0-85014995749000393566000057https://academic.oup.com/mnras/article/463/3/3021/26466332016MNRAS.463.3021BFIS/05 - ASTRONOMIA E ASTROFISICAERC sectors::Physical Sciences and Engineering::PE9 Universe sciences: astro-physics/chemistry/biology; solar systems; stellar, galactic and extragalactic astronomy, planetary systems, cosmology, space science, instrumentation::PE9_8 Formation and evolution of galaxies