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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.


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.


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.


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

We calculate the three-loop anomalous dimension of the non-singlet transverse operator from N=1 to N=15. Using some guess we have reconstructed a general form of three-loop anomalous dimension for arbitrary Mellin moment N. Obtained result is transformed into Bjorken- x space by an inverse Mellin transformation. The final expressions are presented in both Mellin- N and Bjorken- x space. © 2012 Elsevier B.V.


Velizhanin V.N.,RAS Petersburg Nuclear Physics Institute
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2011

We calculate the renormalization constants of the maximally extended N=4 supersymmetric Yang-Mills theories in the dimensional reduction scheme up to four loops. We have found, that the beta-function is zero both from gauge and Yukawa vertices. © 2011 Elsevier B.V.


Grant
Agency: European Commission | Branch: H2020 | Program: CSA | Phase: INFRASUPP-6-2014 | Award Amount: 1.70M | Year: 2015

This CREMLIN proposal is to foster scientific cooperation between the Russian Federation and the European Union in the development and scientific exploitation of large-scale research infrastructures. It has been triggered by the recent so-called megascience projects initiative launched by and in the Russian Federation which is now very actively seeking European integration. The proposed megascience facilities have an enormous potential for the international scientific communities and represent a unique opportunity for the EU to engage in a strong collaborative framework with the Russian Federation. The CREMLIN proposal is a first and path finding step to identify, build and enhance scientific cooperation and strong enduring networks between European research infrastructures and the corresponding megascience facilities to maximize scientific returns. The proposal follows the specific recommendations of an EC Expert Group by devising concrete coordination and support measures for each megascience facility and by developing common best practice and policies on internationalisation and opening. CREMLIN will thus effectively contribute to better connect Russian RIs to the European Research Area.


Grant
Agency: European Commission | Branch: FP7 | Program: CP | Phase: INFRA-2011-2.1.1. | Award Amount: 10.17M | Year: 2011

Key questions in physics can be answered only by constructing a giant underground observatory to search for rare events and study terrestrial and astrophysical neutrinos. The Astroparticle Roadmap of ApPEC/ASPERA strongly supports this, recommending that: a new large European infrastructure of 100000-500000 ton for proton decay and low-energy neutrinos be evaluated as a common design study together with the underground infrastructure and eventual detection of accelerator neutrino beams. The latest CERN roadmap also states: a range of very important non-accelerator experiments takes place at the overlap of particle and astroparticle physics exploring otherwise inaccessible phenomena; Council will seek with ApPEC a coordinated strategy in these areas of mutual interest. Reacting to this, uniting scientists across Europe with industrial support to produce a very strong collaboration, the LAGUNA FP7 design study has had a very positive effect. It enabled, via study of seven pre-selected locations (Finland, France, Italy, Poland, Romania, Spain and UK), a detailed geo-technical assessment of the giant underground cavern needed, concluding finally that no geo-technical show-stoppers to cavern construction exist. Building on this, the present design study will address two challenges vital to making a final detector and site choice: (i) to determine the full cost of construction underground, commissioning and long-term operation of the infrastructure, and (ii) to determine the full impact of including long baseline neutrino physics with beams from CERN.


Grant
Agency: European Commission | Branch: FP7 | Program: CPCSA | Phase: INFRA-2010-1.2.1 | Award Amount: 70.14M | Year: 2010

Scientific research is no longer conducted within national boundaries and is becoming increasing dependent on the large-scale analysis of data, generated from instruments or computer simulations housed in trans-national facilities, by using e Infrastructure (distributed computing and storage resources linked by high-performance networks).\nThe 48 month EGI-InSPIRE project will continue the transition to a sustainable pan-European e-Infrastructure started in EGEE-III. It will sustain support for Grids of high-performance and high-throughput computing resources, while seeking to integrate new Distributed Computing Infrastructures (DCIs), i.e. Clouds, SuperComputing, Desktop Grids, etc., as they are required by the European user community. It will establish a central coordinating organisation, EGI.eu, and support the staff throughout Europe necessary to integrate and interoperate individual national grid infrastructures. EGI.eu will provide a coordinating hub for European DCIs, working to bring existing technologies into a single integrated persistent production infrastructure for researchers within the European Research Area.\nEGI-InSPIRE will collect requirements and provide user-support for the current and new (e.g. ESFRI) users. Support will also be given for the current heavy users as they move their critical services and tools from a central support model to ones driven by their own individual communities. The project will define, verify and integrate within the Unified Middleware Distribution, the middleware from external providers needed to access the e-Infrastructure. The operational tools will be extended by the project to support a national operational deployment model, include new DCI technologies in the production infrastructure and the associated accounting information to help define EGIs future revenue model.

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