Experimental data are given on the time structure of the disk in an extensive air shower recorded with the Moscow University EAS apparatus. Distributions have been derived for the particles over the depth of the shower disk and the radii of curvature for the shower front for the distance range from the axis 200-600 m.
Show AbstractThe paper discusses problems in researching primary cosmic rays in the energy range up to $\approx10^{15}$ eV. Methods are surveyed, and some results are presented that have been obtained with the Proton and Intercosmos-6 satellites and from research on the chemical composition of the nuclear component in the range E > l TeV with the Cosmos-1543 satellite.
Show AbstractData are given on the secondary-electron spatial distribution of energies > 15 MeV and the same for protons with energy > 400 MeV at a height of about 500 km, which have been recorded with a Cherenkov counter on the Cosmos 900 satellite in 1977-1979. There is a longitudinal dependence in the magnetic shelves at middle lattitudes, where the secondary-particle flux in a given L shell increases with the geomagnetic-field induction.
Show AbstractMeasurements have been made with the Prcgnoz satellite and the Venus space probes, which are used in considering the conditions for the generation of high-energy particles: electrons with E > 0.25 MeV and protons as well as heavier nuclei (E > 0.30 MeV/nucleon) during solar flares. There is a good correlation between the amplitudes of the flare-electron fluxes and those of the thermal X-radiation. There are two types of event in solar cosmic rays: accompanied or unaccompanied by bursts of hard X-radiation, and a model is discussed to explain this.
Show AbstractA solution has been obtained by an approximate analytic method fdr the electron-nuclear cascade equation giving the nonscaling inclusive spectra with allowance for the ionizati.on losses and decay in a homogeneous medium. An estimate is made of the accuracy, and the results are compared with those for scaling and logarithmic cross section increase. The results and the method can be used to calculate average characteristics and some first moments of the particle-number distributions for water and the atmosphere.
Show AbstractData are examined on the spatial distributions of the solar cosmic-ray fluxes in the magnetosphere. The boundaries of the polar cap and the plasma layer have been identified. There is a relationship between structure change in these fluxes arising from the pressure of the solar wind and the direction and magnitude of the interplanetary magnetic field. The structure of the high-latitude electron fluxes of magnetosphere origin is compared with model concepts on particle motion in the magnetosphere.
Show AbstractThe paper discusses processes in remote parts of the magnetosphere and polar ionosphere coupled by longitudinal electric currents. The currents in the tail of the magnetosphere have a component perpendicular to the neutral layer, and they provide nondissipative force-line linkage, whose rate is determined by the ionosphere's conductivity.
Show AbstractMeasurements have been made on the spin tensors $\rho_{k\kappa}(\vartheta_{y})$ of even rank in the density matrix for the 2$^+$ state of $^{12}$С formed in $^{12}$С$^\ast$ with $E_{\alpha}=30$ MeV and $^{13}$C($^3$Не, $\alpha'$)$^{12}$С$^\ast$ with $E_{{^3}\text{He}}=22.5$ MeV. The resulting $\rho_{k\kappa}(\vartheta_{y})$ have been used to obtain the angular dependence of the orientation tensors for the quadrupole and hexadecapole moments of the 2$^+$ state of $^{12}$С.
Show AbstractNew data are presented on the partial decay channels for the giant dipole resonance (GDR) of $^{40}$Са. In all, information has been obtained on 33 partial photoreaction channels, of which 16 have not been observed before. In particular, information has been obtained on the reactions $(\gamma, 2p_{i})$, $(\gamma, \tau_{i})$, and $(\gamma, \alpha_{i})$. A study is made of the isospin purity of the GDR states. It is found that the mixing of $T=0$ states with $T=1$ ones in the region of the GDR maximum does not exceed 2-3%. The proportions of the semidirect components in the partial photonucleon cross sections have been determined and in the cross section for photoabsorption by $^{40}$Са (the value is 0.55 for the latter).
Show AbstractThe shadow method has been used to examine the fission time for $^{238}$Nр formed by deuteron absorption by $^{238}$U and subsequent emission of two neutrons. The analysis is based on the two-hump fission-barrier model. It is shown that the transition-state lifetimes made a substantial contribution to the fission time for $^{238}$Np.
Show AbstractParameters have been determined for the optical potential OP providing close reproduction of the observed differential cross sections for elastic scattering and polarization, as well as the energy dependence of the total reaction cross section. The energy dependence has been determined for the proton OP parameters for $^{53}$Cr, as well as the energy dependence of the elastic-scattering cross section involving the compound nucleus and the dependence of the exchange integral for the imaginary potential per nucleon on the incident-proton energy.
Show AbstractFaddeev's equations have been modified to incorporate the Coulomb interaction in order to calculate the cross sections for nucleon $N$ stripping reactions $d + A \rightarrow N + B$. It is found that the proton-transfer cross section is larger than the neutron one. Analogous equations are used to describe electron transfer in ion-atom collisions. Total cross sections have been calculated for these reactions produced by ions with charges $Z=1-6$ at hydrogen and helium atoms, which agree satisfactorily with experiment.
Show AbstractA study is made of scope for using coincidences between scattered particle and the $\gamma$ ray from the daughter nuclide to measure the shape of the Doppler line in research on the shattering mechanism.
Show Abstract
