526 citations · 2.1k across the 38 of their papers we have counts for
30 papers · 1 filter
UVES radial velocity accuracy from asteroid observations. Implications for the fine structure constant variability
P. Molaro, S. A. Levshakov, S. Monai +4
High resolution observations of the asteroids Iris and Juno have been performed by means of the UVES spectrograph at the ESO VLT to obtain the effective accurac y of the spectrogra…
A new measure of Delta alpha/alpha at redshift z = 1.84 from very high resolution spectra of Q1101-264
S. A. Levshakov, P. Molaro, S. Lopez +5
We probe the evolution of the fine-structure constant, alpha, with cosmic time. Accurate positions of the FeII lines 1608, 2382,and 2600 A are measured in the z = 1.84 absorption s…
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…
Extinction and metal column density of HI regions up to redshift z~2
G. Vladilo, M. Centurion, S. A. Levshakov +4
We used the photometric database of the Sloan Digital Sky Survey (SDSS) to estimate the reddening of 13 SDSS quasars selected on the basis of the presence of zinc absorption lines…
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…
Most precise single redshift bound to the variability of the fine-structure constant
S. A. Levshakov, M. Centurion, P. Molaro +4
Verification of theoretical predictions of an oscillating behavior of the fine-structure constant, alpha, with cosmic time requires high precision measurements at individual redshi…