M. V. Marchenko

Publications (4)0 Total impact

• Source

  Available from: arxiv.org

  Article: Calculation of the dependence of transition frequencies on the fine structure constant and the search for variation of alpha in QSO spectra

  J. C. Berengut, V. A. Dzuba, V. V. Flambaum, M. V. Marchenko
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  ABSTRACT: We calculate the dependence of atomic transition frequencies on the fine structure constant, $\alpha = e^2/\hbar c$, for some ions of Ti, Mn, Na, C, and O. The results of these calculations will be used in the search for variation of alpha in quasar absorption spectra.
  09/2004;
• Source

  Available from: V. A. Dzuba

  Article: Laboratory spectroscopy and the search for space-time variation of the fine structure constant using QSO spectra

  J. C. Berengut, V. A. Dzuba, V. V. Flambaum, M. G. Kozlov, M. V. Marchenko, M. T. Murphy, J. K. Webb
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  ABSTRACT: Theories unifying gravity with other interactions suggest spatial and temporal variation of fundamental ``constants'' in the Universe. A change in the fine structure constant, alpha, could be detected via shifts in the frequencies of atomic transitions in quasar absorption systems. Previous studies of three independent samples of data, containing 143 absorption systems spread from 2 to 10 billion years after big bang, hint that alpha was smaller 7 - 11 billion years ago. To continue this study we urgently need accurate laboratory measurements of atomic transition frequencies. In this paper, we present a current list of transitions of importance to the search for alpha variation. They are E1 transitions to the ground state in several different atoms and ions, with wavelengths ranging from around 900 - 6000 Angstroms, and require an accuracy of better than 10^(-4) Angstroms. We also discuss isotope shift measurements that are needed in order to resolve systematic effects in the study. Researchers who are interested in performing these measurements should contact the authors directly.
  09/2004;
• Source

  Available from: V. A. Dzuba

  Article: The alpha-dependence of transition frequencies for some ions of Ti, Mn, Na, C, and O, and the search for variation of the fine structure constant

  J. C. Berengut, V. A. Dzuba, V. V. Flambaum, M. V. Marchenko
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  ABSTRACT: We use the relativistic Hartree-Fock method, many-body perturbation theory and configuration-interaction method to calculate the dependence of atomic transition frequencies on the fine structure constant, alpha. The results of these calculations will be used in the search for variation of the fine structure constant in quasar absorption spectra.
  05/2004;
• Source

  Available from: V. A. Dzuba

  Article: Relativistic effects in Sr, Dy, YbII and YbIII and search for variation of the fine structure constant

  V. A. Dzuba, V. V. Flambaum, M. V. Marchenko
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  ABSTRACT: A possibility for fundamental constants to vary in time is suggested by theories unifying gravity with other interactions. In this article we examine proposals to use optical transitions of Sr, Dy, YbII and YbIII for the search of the time variation of the fine structure constant $\alpha$. Frequencies of atomic transitions are calculated using relativistic Hartree-Fock method and configuration interaction technique. The effect of variation of $\alpha$ on the frequencies is studied by varying $\alpha$ in computer codes. Accuracy of measurements needed to improve current best limit on the time variation of $\alpha$ is discussed.
  06/2003;