207 citations · 2.7k across the 59 of their papers we have counts for
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The precision of line position measurements of unresolved quasar absorption lines and its influence on the search for variations of fundamental constants
Nils Prause, Dieter Reimers
Optical quasar spectra can be used to trace variations of the fine-structure constant alpha. Controversial results that have been published in last years suggest that in addition t…
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…
Metal-rich absorbers at high redshifts: abundance patterns
S. A. Levshakov, I. I. Agafonova, P. Molaro +2
(Abbreviated) From six spectra of high-z QSOs, we select eleven metal-rich, Z>=Z_solar, and optically-thin to the ionizing radiation, N(HI)<10^17 cm^-2, absorption systems ranging…
Transition frequency shifts with fine-structure constant variation for Fe I. Isotope shift calculations in Fe I and Fe II
S. G. Porsev, M. G. Kozlov, D. Reimers
In this paper we calculated the relativistic corrections to transition frequencies (q factors) of Fe I for the transitions from the even- and odd-parity states to the ground state.…