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L. V. Fil'kov

Publications and source records attributed to L. V. Fil'kov.

62 records · Page 4Linked to original sources
arXiv2000

Fishing for Narrow Dibaryons in pd->pX Reaction

An analysis of experimental data, obtained at the Linear Accelerator of INR, is carried out with the aim of searching for supernarrow dibaryons in the reactions pd->p+X and pd->p+pX_1. Dibaryons with masses 1904\pm 2, 1926\pm 2, and 1942\pm 2 MeV have been observed in M_{X} missing mass spectra. In M_{X_1} missing mass spectra, the peaks have been found at M_{X_1}=966\pm 2, 986\pm 2, and 1003\pm 2 MeV. These values of M_{X_1} coincide with the ones obtained by a simulation of a decay of the dibaryons into γ+pn. The analysis of the data obtained leads to the conclusion that the observed dibaryons are supernarrow dibaryons, the decay of which into two nucleons is forbidden by the Pauli exclusion principle. A possible interpretation of exited nucleon states with small masses is suggested.

nucl-th↗
arXiv2000

Search for Supernarrow Dibaryons in pd Interactions

The reaction pd-->pX at 305 MeV is studied with the aim to search for supernarrow dibaryons, the decay of which into two nucleons is forbidden by the Pauli exclusion principle. The experiment was carried out at the Moscow Meson Factory using the spectrometer TAMS, which detected the scattered proton in coincidence with another charged particle (either p or d) from the decay of particle X. The detection of the second charged particle at angles close to the emission angle of particle X with mass M allows to suppress essentially the contribution of background processes and to increase the relative contribution of a possible production of the dibaryons under consideration. Narrow peaks in missing mass spectra have been observed at 1905 and 1924 MeV with the statistical significance of ~4.8 SD. The widths of both observed peaks correspond to the experimental resolution (3 MeV). Comparison of the obtained data with theoretical predictions leads to the conclusion that the peak found at 1905 MeV most likely corresponds to a supernarrow dibaryon with the isotopic spin equal to 1. The possible origin of the peak at 1924 MeV is also discussed.

hep-ex↗
arXiv2000

Study of supernarrow dibaryon production in process pd-->pX

The reactions p+d-> p+pX and p+d-> p+dX at 305 MeV are studied with the aim to search for supernarrow dibaryons, decay of which into two nucleons is suppressed by the Pauli principle. The experiment was carried out at the Moscow Meson Factory using a spectrometer TAMS, which detected the scattered proton in coincidence with the second charged particle (the proton or deuteron) at various angles. Narrow peaks at 1905 and 1924 MeV with widths less than the experimental resolution (3 MeV) have been observed in missing- mass spectra of the process pd->pX. An analysis of the angular dependence of the experimental data shows that the resonance at $M$=1905 MeV most likely corresponds to the production of the isovector supernarrow dibaryon.

nucl-ex↗
arXiv1999

Compton Scattering on the Charged Pion and the Process γγ\to π^0 π^0

The Compton scattering on a charged pion and the process γγ\to π^0π^0 are studied using the dispersion relations. Unknown parameters of the S-wave ππinteraction, represented as a board Breit-Wignar resonance, and a sum and a difference of the π^0 meson polarizabilities are found from a fit to the experimental data for the process γ+γ\to π^0+π^0. This fit gives α+β=0.98\pm 0.03 and α-β=-1.6\pm 2.2. The found parameters of the S-wave ππinteraction are used for the calculation of the cross section of the Compton scattering on π^{\pm} meson. The analysis of the obtained results shows that the experimental data for the elastic γπscattering in the energy region up to 1 GeV together with the data for the process γ+γ\to π^0+π^0 could be used both for a determination of the pion polarizability values with quite high accuracy and for study of the S-wave ππinteraction.

nucl-th↗
arXiv1998

Compton Scattering on Pion and Pion Polarizabilities

The Compton scattering on a charged pion is studied using the dispersion relations. Unknown mass, full width and decay width into γγof the sigma meson are found from a fit to the experimental data for the process γ+γ\to π^0+π^0. These parameters are used for the calculation of the cross section of the Compton scattering on the charged pion. The analysis of the obtained results shows that the data on the elastic γ\pion scattering in the energy region up to \sqrt{s}=1 GeV (together with the data on process γγ\to π^0π^0) could be used both for a determination of the pion polarizability values with high precision and for research of the sigma meson.

hep-ph↗
arXiv1997

Hydrodynamical Evolution of a Quark-Gluon Plasma Drop With Boundary

We consider the evolution of a spherically symmetric Quark-Gluon Plasma (QGP) drop with limited size in the framework of relativistic hydrodynamics. In the presence of the boundary, the expanding and cooling of QGP drop may appear as oscillating processes, which realize via multiple traveling of rarefaction and compression waves through the plasma and lead to increasing of plasma life-time. Within this picture, deflagration is the main possible way of hadronization. The slow cooling mechanism also leads to a significant enhancement of photon yield in comparison with Bjorken scenario.

nucl-th↗
arXiv1996

Possibility of observation of supernarrow dibaryons with symmetric wave function in $γd --> π^{\pm}+γNN$ reactions

The possibility of obsevation of supernarrow dibaryons with symmetric wave function in reactions $γ+d to π^+ +γ+nn$ and $γ+d to π^- +γ+pp$ is studied. These dibaryons satisfy the condition $(-1)^{T+S}P=+1$ (where T is the isospin, S is the internal spin and P is the dibaryon parity) and their decay into two nucleons is suppressed by the Pauly principle. In the present paper the method of a dibaryon masses reconstruction over the dibaryon decay products (γnn) and (γpp) is analysed. The Monte-Carlo simulation is used to choose the optimal location of the detectors, to estimate the contribution of the main background processes and to calculate the expected yields of the dibaryon production. It is shown that 100 hours of the exposition time at the microtron MAMI (Mainz) is quite enough to determine whether or not the supernarrow dibaryons with symmetric wave function exist.

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