Sergei Levshakov

Calibration issues in estimating variability of the fine structure constant (alpha) with cosmic time (2009)

Centurión, Miriam, Molaro, Paolo, Levshakov, Sergei

Laser Comb Wavelength calibration shows that the ThAr one is locally unreliable with possible deviations of up to 100 m/s within one order range, while delivering an overall 1 m/s accuracy (Wilken et...

Measurability Of Kinetic Temperature From Metal Absorption-Line Spectra Formed In Chaotic Media (2007)

Sergei Levshakov, Fumio Takahara, Irina I. Agafonova

We present a new method for recovering the kinetic temperature of the intervening di+use gas to an accuracy of 10%. The method is based on the comparison of unsaturated absorption-line proles of two...

Exploring variations in the fundamental constants with ELTs: The CODEX spectrograph on OWL (2006)

Molaro, Paolo, Murphy, Michael T., Levshakov, Sergei, Di Trieste, Osservatorio Astronomico, ...

Cosmological variations in the fine structure constant, alpha, can be probed through precise velocity measurements of metallic absorption lines from intervening gas clouds seen in spectra of distant...

CODEX : measuring the expansion of the universe (2005)

Pasquini, Luca, Cristiani, Stefano, Dekker, Hans, Haehnelt, Martin, Molaro, Paolo, Pepe, Francesco, ...

CODEX, a high-resolution, super-stable spectrograph to be fed by OWL, the most powerful telescope ever conceived, will for the first time provide the possibility of directly measuring the change of...

CODEX : measuring the expansion of the universe (2005)

Pasquini, Luca, Cristiani, Stefano, Dekker, Hans, Haehnelt, Martin, Molaro, Paolo, Pepe, Francesco, ...

CODEX, a high-resolution, super-stable spectrograph to be fed by OWL, the most powerful telescope ever conceived, will for the first time provide the possibility of directly measuring the change of...

CODEX : measuring the expansion of the universe (2005)

Pasquini, Luca, Cristiani, Stefano, Dekker, Hans, Haehnelt, Martin, Molaro, Paolo, Pepe, Francesco, ...

CODEX, a high-resolution, super-stable spectrograph to be fed by OWL, the most powerful telescope ever conceived, will for the first time provide the possibility of directly measuring the change of...

How Accurately Can the Deuterium Abundance Be Determined ? (1997)

Sergei Levshakov, Wilhelm H. Kegel, Fumio Takahara, N Hi

h respect to the H+D absorption observed in QSO spectra. The hydrogen absorbers with N HI ¸ 10 17 \Gamma 10 18 cm \Gamma2 (which are especially useful for deuterium observations) are usually...