258 citations · 2.1k across the 69 of their papers we have counts for
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Probing the variability of the fine-structure constant with the VLT/UVES
Ralf Quast, Dieter Reimers, Sergei A. Levshakov
We assess the cosmological variability of the fine-structure constant from the analysis of an ensemble of Fe II absorption lines at the redshift z=1.15 toward the QSO HE 0515-4414…
Astrophysical constraints on hypothetical variability of fundamental constants
Sergei A. Levshakov
(Abridged) Many-multiplet (MM) method applied to three inhomogeneous samples of Keck/HIRES quasar absorption spectra gives a shift in the value of the fine-structure constant of De…
Metal Abundances and Kinematics of the Ly-alpha absorbers
Sergei A. Levshakov
Both high resolution spectra of QSOs observed at the 8-10m telescopes and advanced methods of data analysis are crucial for accurate measurements of the chemical composition and ph…
The broad OVI absorber at z = 3.02 toward CTQ 325
S. A. Levshakov, S. D'Odorico, I. I. Agafonova +1
We report on the multiphase absorption-line system detected at a redshift z = 3.021 in the spectrum of the quasi-stellar object CTQ 325 (z_em = 3.212). The system is displaced by ~…
Detection of molecular hydrogen at z=1.15 toward HE 0515-4414
D. Reimers, R. Baade, R. Quast +1
A new molecular hydrogen cloud is found in the sub-damped Ly-alpha absorber [log N(HI)=19.88+/-0.05] at the redshift z=1.15 toward the bright quasar HE0515-4414 (zem = 1.71). More…
Photoionized OVI absorbers toward the bright QSO HE 0515-4414
S. A. Levshakov, I. I. Agafonova, D. Reimers +1
We report on detailed Monte Carlo inversion analysis of five OVI systems from the spectrum of the bright quasar HE 0515-4414 (z_e = 1.71). The associated system at z_a = 1.697 with…