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G. M. Vereshkov

Publications and source records attributed to G. M. Vereshkov.

13 recordsLinked to original sources
arXiv2013

On evolution of Primary Cosmic Ray mass composition in the energy region $10^{14}-10^{16}$ eV

A new method of determining Primary Cosmic Ray mass composition is proposed. The method is based on quasi-localization of the integral equation for the Extensive Air Showers spectrum versus the total number of high energy muons ($E_μ\geqslant 235$ GeV) and an expansion of the experimentally measured spectrum in spectra of five group of primary nuclei. The cosmic ray mass composition is established in the energy region $10^{14}-10^{16}$ eV. In the region $10^{15}-10^{16}$ eV our analysis points to a lightening of the mass composition from $p+α\simeq 0.54,\ \langle \ln A \rangle \simeq 1.97$ to $p+α\simeq 0.69,\ \langle \ln A \rangle\simeq 1.56$.

hep-ph↗
arXiv2011

On the mass composition of primary cosmic rays in the energy region 10^15-10^16 eV

The method of a determination of the Primary Cosmic Ray mass composition is presented. Data processing is based on the theoretical model representing the integral muon multiplicity spectrum as the superposition of the spectra corresponding to different kinds of primary nuclei. The method consists of two stages. At the first stage, the permissible intervals of primary nuclei fractions f_i are determined on the base of the EAS spectrum vs the total number of muons (E_mu > 235 GeV). At the second stage, the permissible intervals of f_i are narrowed by fitting procedure. We use the experimental data on high multiplicity muon events (n_mu > 114) collected at the Baksan underground scintillation telescope. Within the framework of three components (protons, helium and heavy nuclei), the mass composition in the region 10^15-10^16 eV has been defined: f_p = 0.235 +- 0.02, f_He = 0.290 +- 0.02$, f_H = 0.475 +- 0.03.

hep-ph↗
arXiv2009

Neutralino-nucleon interaction in the Split SUSY scenario of the Dark Matter

The Split SUSY scenario with light Higgsino states is treated as an application to the Dark Matter problem. We have considered the structure of the neutralino-nucleon interaction and calculated cross-section of the neutralino-nucleon scattering. The decay properties of the lightest chargino and next lightest neutralino are analyzed in details.

hep-ph↗
arXiv2008

Diagonalization of the neutralino mass matrix and boson-neutralino interaction

We analyze a connection between neutralino mass sign, parity and structure of the neutralino-boson interaction. Correct calculation of spin-dependent and spin-independent contributions to neutralino-nuclear scattering should consider this connection. A convenient diagonalization procedure, based on the exponetial parametrization of unitary matrix, is suggested.

hep-ph↗
arXiv2006

High energy Gamma-Ray Bursts as a result of the collapse and total annihilation of neutralino clumps

Rare astrophysical events - cosmological gamma-ray bursts with energies over GeV - are considered as an origin of information about some SUSY parameters. The model of generation of the powerful gamma-ray bursts is proposed. According to this model the gamma-ray burst represents as a result of the collapse and the total annihilation of the neutralino clump. About 80 % of the clump mass radiates during about 100 second at the final stage of annihilation. The annihilation spectrum and its characteristic energies are calculated in the framework of Split Higgsino model.

hep-ph↗
arXiv2004

Estimation of charm production cross section in hadronic interactions at high energies

Results of processing experimental data on charm production in hadron-hadron interactions are presented. The analysis is carried out within the frame of phenomenological model of diffraction production and quark statistics based on additive quark model (AQM). In low energy region sqrt s = 20 - 40GeV, the cross sections si_ {pN to c bar cX} (s), si_ {pi N to c bar cX} (s) are fitted by logarithmic function with the parameters connected by relationship of AQM. At collider energies 200, 540, 900, 1800 GeV, the values of si_{bar pp to c bar cX} (s) were obtained by a quark statistics method from the data on diffraction dissociation. It is established, that logarithmic function with universal numerical parameters describes the whole set of low-energy and high-energy data with high accuracy. The expected values of cross sections are si_{pp to c bar cX} = 250 pm 40 mu b and 355 pm 57 mu b at TEVATRON energy sqrt {s} = 1.96 TeV and LHC energy sqrt {s} = 14 TeV accordingly. Opportunities of use of the obtained results for calibration of a flux of "prompt" muons in high-energy component of cosmic rays are discussed.

hep-ex↗
arXiv2003

A fitting function for the SNAP data

A mathematically motivated fitting function for analyzing supernovae distance-redshift data is suggested. It is pointed out that this function can be useful in analyzing SNAP data. To illustrate our method, we analyze current experimental data which includes 78 supernovae and 20 radio galaxies. From these data we obtain vacuum equation of state in a model independent way. We show that the flat Universe model with a cosmological constant is in a good agreement with observations.

astro-ph↗
arXiv2002

Topological Vacuum of the Closed Universe as a Gauging Factor

The only known general base to eliminate the vacuum divergencies of quantized matter fields in quantum geometrodynamics is the fermion-boson supersymmetry. The topological effect of the closed Universe -- discretization of the vacuum fluctuations spectra -- allows to formulate the conditions of cancellation of the divergencies. In the center of attention of this work is the fact that these conditions result in the considerable restrictions on the gauge and factor-ordering ambiguities peculiar to the equations of the theory and, in the limits of the isotropic model of the Universe, remove these ambiguities completely.

gr-qc↗
arXiv2000

Quantum geometrodynamics in extended phase space - II. The Bianchi IX model

The mathematically correct approach to constructing quantum geometrodynamics of a closed universe formulated in Part I is realized on the cosmological Bianchi-IX model with scalar fields. The physical adequacy of the obtained gauge-noninvariant theory to existing concepts about possible cosmological scenarios is shown. It is demonstrated that the Wheeler-DeWitt quantum geometrodynamics based on general quantum theoretical principles with probability interpretation of a closed universe wave function does not exist. The problem of the creation of the Universe is considered as a computational problem of a quantum reduction of the singular state "Nothing" to one of possible initial physical quantum states.

gr-qc↗
arXiv2000

Quantum geometrodynamics in extended phase space - I. Physical problems of interpretation and mathematical problems of gauge invariance

The paper is the first of two parts of the work devoted to the investigation of constructing quantum theory of a closed universe as a system without asynptotic states. In Part I the role of asymptotic states in quantum theory of gravity is discussed, that enables us to argue that mathematically correct quantum geometrodynamics of a closed universe has to be gauge-noninvariant. It is shown that a gauge-noninvariant quantum geometrodynamics is consistent with the Copenhagen interpretation. The proposed version of the theory is thought of as describing the integrated system ``the physical object + observation means''. It is also demonstrated that introducing the observer into the theory causes the appearance of time in it.

gr-qc↗
arXiv2000

The exact cosmological solution to the dynamical equations for the Bianchi IX model

Quantum geometrodynamics in extended phase space describes phenomenologically the integrated system ``a physical object + observation means (a gravitational vacuum condensate)''. The central place in this version of QGD belongs to the Schrodinger equation for a wave function of the Universe. An exact solution to the ``conditionally-classical'' set of equations in extended phase space for the Bianchi-IX model and the appropriate solution to the Schrodinger equation are considered. The physical adequacy of the obtained solutions to existing concepts about possible cosmological scenarios is demonstrated. The gravitational vacuum condensate is shown to be a cosmological evolution factor.

gr-qc↗
arXiv1999

Quantum geometrodynamics of the Bianchi IX model in extended phase space

A way of constructing mathematically correct quantum geometrodynamics of a closed universe is presented. The resulting theory appears to be gauge-noninvariant and thus consistent with the observation conditions of a closed universe, by that being considerably distinguished from the conventional Wheeler - DeWitt one. For the Bianchi-IX cosmological model it is shown that a normalizable wave function of the Universe depends on time, allows the standard probability interpretation and satisfies a gauge-noninvariant dynamical Schrodinger equation. The Wheeler - DeWitt quantum geometrodynamics is represented by a singular, BRST-invariant solution to the Schrodinger equation having no property of normalizability.

gr-qc↗