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Kozlov M.G.,RAS Petersburg Nuclear Physics Institute
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2013

In polyatomic molecules with a Π electronic ground state, the rovibrational spectrum can be strongly modified by the Renner-Teller effect (the coupling between bending vibrational mode and electrons in the degenerate Π state). The linear form of the C3H molecule has particularly strong Renner-Teller interactions and a very-low-lying vibronic Σ1/2+ level, which corresponds to the excited bending vibrational mode. This leads to the increased sensitivities of the microwave and submillimeter transition frequencies to the possible variation of the fine structure constant α and electron-to-proton mass ratio μ. © 2013 American Physical Society.

Azimov Y.I.,RAS Petersburg Nuclear Physics Institute
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2011

Proof of the Froissart theorem is reconsidered in a different way to extract its necessary conditions. Two physical inputs, unitarity and absence of massless intermediate hadrons, are indisputable. Also important are mathematical properties of the Legendre functions. Assumptions on dispersion relations, single or double, appear to be excessive. Instead, one should make assumptions on possible high-energy asymptotics of the amplitude in nonphysical configurations, which have today no firm basis. Asymptotics for the physical amplitude always appear essentially softer than for the nonphysical one. Froissart's paper explicitly assumed the hypothesis of power behavior and obtained asymptotic bound for total cross sections ∼log2(s/s 0) with some constant s0. Our bounds are slightly stronger than original Froissart ones. They show that the scale s0 should itself slowly grow with s. Under different assumptions about asymptotic behavior of nonphysical amplitudes, the total cross section could grow even faster than log2s. The problem of correct asymptotics might be clarified by precise measurements at the LHC and higher energies. © 2011 American Physical Society.

Velizhanin V.N.,RAS Petersburg Nuclear Physics Institute
Journal of High Energy Physics | Year: 2010

The result for the six-loop anomalous dimension of twist-three operators in the planar N = 4 SYM theory is presented. The calculations were performed along the paper arXiv:0912.1624. This result provides a new data for testing the proposed spectral equations for planar AdS/CFT correspondence. © 2010 SISSA.

Bulat S.A.,RAS Petersburg Nuclear Physics Institute
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences | Year: 2016

This article examines the question of the possible existence of microbial life inhabiting the subglacial Lake Vostok buried beneath a 4 km thick Antarctic ice sheet. It represents the results of analysis of the only available frozen lake water samples obtained upon the first lake entry and subsequent re-coring the water frozen within the borehole. For comparison, results obtained by earlier molecular microbiological studies of accretion ice are included in this study, with the focus on thermophiles and an unknown bacterial phylotype. A description of two Lake Vostok penetrations is presented for the first time from the point of view of possible clean water sampling. Finally, the results of current studies of Lake Vostok frozen water samples are presented, with the focus on the discovery of another unknown bacterial phylotype w123-10 distantly related to the above-mentioned unknown phylotype AF532061 detected in Vostok accretion ice, both successfully passing all possible controls for contamination. The use of clean-room facilities and the establishment of a contaminant library are considered to be prerequisites for research on microorganisms from Lake Vostok. It seems that not yet recorded microbial life could exist within the Lake Vostok water body. In conclusion, the prospects for searching for lake inhabitants are expressed with the intention to sample the lake water as cleanly as possible in order to make sure that further results will be robust. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Velizhanin V.N.,RAS Petersburg Nuclear Physics Institute
Nuclear Physics B | Year: 2012

We present the result of a calculation for the first even moment of the non-singlet four-loop anomalous dimension of Wilson twist-2 operators in QCD with full color and flavor structures. © 2012 Elsevier B.V.

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