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I. N. Nikitin

Publications and source records attributed to I. N. Nikitin.

6 recordsLinked to original sources

Search and detection of pulsars in the monitoring observations at the frequency 111 MHz

Pulsars with periods more than 0.4 seconds in the declination range -9o < decj < 42o and in the right ascension range 0h < r.a.< 24h were searched in parallel with the program of interplanetary scintillations monitoring of a large number of sources with the radiotelescope LPA LPI. Four-year observations carried out at the central frequency 110.25 MHz in the band 2.5 MHz and in six frequency channels with the time resolution 100 ms were used for the search. Initial detections of candidates for pulsars were based on the Fourier power spectra averaged over the whole observations period. The candidates for pulsars were checked in more details from observations analysis with higher time-frequency resolution: 32 frequency channels with time resolution of 12.5 ms. 18 new pulsars was discovered, their main characteristics are presented.

astro-ph.HE

Numerical Methods for the 3-dimensional 2-body Problem in the Action-at-a-Distance Electrodynamics

We develop two numerical methods to solve the differential equations with deviating arguments for the motion of two charges in the action-at-a-distance electrodynamics. Our first method uses Stürmer's extrapolation formula and assumes that a step of integration can be taken as a step of light ladder, which limits its use to shallow energies. The second method is an improvement of pre-existing iterative schemes, designed for stronger convergence and can be used at high-energies.

hep-th

On Continuous Ambiguities in Model-Independent Partial Wave Analysis. Part 1

A problem of amplitude reconstruction in terms of the given angular distribution is considered. Solution of this problem is not unique. A class of amplitudes, correspondent to one and the same angular distribution, forms a region in projection onto a finite set of spherical harmonics. An explicit parametrization of a boundary of the region is obtained. A shape of the region of ambiguities is studied in particular example. A scheme of partial-wave analysis, which describes all solutions in the limits of the region, is proposed.

hep-ph