Publications (8)
VLT/UVES observations of peculiar alpha abundances in a sub-DLA at z ~ 1.8 towards the quasar B1101-26
Anne Fox, Philipp Richter, Cora Fechner
We present a detailed analysis of chemical abundances in a sub-damped Lyman alpha absorber at z=1.839 towards the quasar B1101-26, based on a very-high-resolution (R ~ 75,000) and…
A Measurement of Small Scale Structure in the 2.2 < z < 4.2 Lyman-alpha Forest
Adam Lidz, C. -A. Faucher-Giguere, Aldo Dall'Aglio +5
The amplitude of fluctuations in the Ly-a forest on small spatial scales is sensitive to the temperature of the IGM and its spatial fluctuations. The temperature of the IGM and its…
The End of Helium Reionization at z~2.7 Inferred from Cosmic Variance in HST/COS HeII Lyman Alpha Absorption Spectra
Gábor Worseck, J. Xavier Prochaska, Matthew McQuinn +6
We report on the detection of strongly varying intergalactic HeII absorption in HST/COS spectra of two z~3 quasars. From our homogeneous analysis of the HeII absorption in these an…
Nucleosynthetic signatures of the first stars
Anna Frebel, Wako Aoki, Norbert Christlieb +16
The chemically most primitive stars provide constraints on the nature of the first stellar objects that formed in the Universe; elements other than hydrogen, helium and traces of l…
The COS/UVES Absorption Survey of the Magellanic Stream: II. Evidence for a complex enrichment history of the Stream from the Fairall 9 sightline
Philipp Richter, Andrew J. Fox, Bart P. Wakker +5
We present a multi-wavelength study of the Magellanic Stream (MS), a massive gaseous structure in the Local Group that is believed to represent material stripped from the Magellani…
A population of high-velocity absorption-line systems residing in the Local Group
Sietske J. D. Bouma, Philipp Richter, Cora Fechner
Aims. We aim to investigate the ionisation conditions and distances of Galactic high-velocity clouds (HVCs) in the Galactic halo and beyond in the direction of the Local Group (LG)…
Reconstructing the intergalactic UV background with QSO absorption lines
Cora Fechner
We present a new approach to constrain the spectral energy distribution of the intergalactic UV background observationally by studying metal absorption systems. We study single-com…
The associated system of HE2347-4342
Cora Fechner, Robert Baade, Dieter Reimers
We present an analysis of the complex associated system of the high-redshift QSO HE2347-4342. Absorption features of HI, CIII, CIV, NV, and OVI with up to 16 components occur in th…