258 citations · 590 across the 14 of their papers we have counts for
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High-Precision Measurements of Delta alpha/alpha from QSO Absorption Spectra
Sergei A. Levshakov, Paolo Molaro, Sebastian Lopez +4
Precise radial velocity measurements (delta v/c ~ 10^{-7}) of FeII lines in damped Ly-alpha systems from very high quality VLT/UVES spectra of quasars HE0515-4414 and Q1101-264 are…
Spectral shape of the UV ionizing background and HeII absorption at redshifts 1.8 < z < 2.9
I. I. Agafonova, S. A. Levshakov, D. Reimers +4
The shape of the UV ionizing background is reconstructed from optically thin metal absorption-line systems identified in spectra of HE2347-4342, Q1157+3143, and HS1700+6416 in the…
VLT/UVES constraints on the carbon isotope ratio 12C/13C at z=1.15 toward the quasar HE 0515-4414
S. A. Levshakov, M. Centurion, P. Molaro +1
We analyzed the CI lines associated with the damped Ly-alpha system observed at zabs = 1.15 in the spectrum of HE 0515-4414 to derive the 12C/13C ratio. The spectrum was obtained b…