Proton collisions in cosmic ray sources

In this paper we have studied the possible proton collisions in cosmic ray sources. On the basis of our calculations of background temperature, the operational domains of various proton collisions are suggested. The energy rate loss through the photo-neutrino processes on protons is computed and we have discussed the energy distribution of the secondary particles in various collisions.     

Transient MHD free convection in a rotating system

The classical Rayleigh problem has been extended to the case of the hydromagnetic free-convective flow of an electrically-conducting and incompressible viscous fluid past an infinite vertical naturally permeable wall in a rotating system. The applied transverse magnetic field is fixed with the moving wall and the magnetic Reynolds number of the flow is taken small so that the induced magnetic field can be neglected in comparison to the applied magnetic field. The permeable wall starts moving from rest in the still fluid and thus arises an initial value problem whose solution has been obtained by the Laplace transform method for two important cases impulsive as well as accelerated start of the plate. Mathematical expression for skin friction components have been also obtained in a closed form. Asymptotic behaviour of the solution is analysed for both the cases, and some interesting particular cases have also been encountered. Influence of various physical parameters occurring into the problem has been discussed with the aid of graphs and tables.     

Relative abundances of 10≤Z≤26 nuclei in medium energy cosmic rays

Abundances of primary cosmic-ray nuclei from neon to iron, in the energy interval 200 to 650 MeV n^–1, have been determined using a balloon exposed cellulose nitrate plastic detector. These abundances have been extrapolated back to the source regions using various models of cosmic ray interstellar propagation. Some aspects of cosmic-ray propagation and origin have been discussed in the light of results of the present experiment.     

Hall effects on MHD free-convection flow past an accelerated vertical porous plate

The effect of Hall currents on the hydromagnetic free-convection flow of an electrically conducting and incompressible viscous fluid past a uniformly accelerated infinite vertical porous plate is discussed. The magnetic Reynolds number is assumed to be small so that the induced magnetic field can be neglected. The governing equations of the flow are solved by defining a complex velocity with the help of the Laplace transform method when the Prandtl number is equal to unity. The influence of the various parameters on the unsteady flow field is presented for both the cases, cooling and heating of the porous plate by free-convection currents.     

Energy loss of protons in the molecular oxygen

A theoretical study of the proton loss function in the molecular oxygen based on the most appropriate elastic and inelastic cross-sections is made. The earlier results of the loss function are modified for ionization, charge exchange and elastic scattering. The present results are in good agreement with experiment.     

Tidal effects of the galaxy on a globular cluster

Tidal effects of a Schmidt (1965) model galaxy on a typical globular cluster moving in an orbit along the axis of symmetry of the spheroid is studied under the impulsive approximation. Ann-body simulation is made for comparison. Results show that in both cases, a high concentration cluster gains enough energy to be totally dissolved within a distance of 2 kpc. A significant mass loss occurs as the cluster approaches the Roche distance.