• VINOD KUMAR

Articles written in Pramana – Journal of Physics

• Comments on the number of sensitivity centres in silver halide grains

A comment on the number of sensitivity centres in silver halide grains of nuclear emulsions is made and a theory for its evaluation at different temperatures is presented. The results at room temperature agree satisfactorily with assumptions made by various workers.

• On the behaviour of Er3+ ion in tetragonal crystalline field

Crystal field parameters for ErGaG and Er3+ YAlG and used to compute the temperature dependence of Schottky specific heat, paramagnetic susceptibility, magnetic anisotropy,μeff and quadrupole splitting in the range 10–400 K. The hyperfine interaction parametersA andB for166Er and167Er in both the systems are also obtained and in turn used to estimate the nuclear specific heat contribution. The studied parameters compare well with the available experimental results.

• Laser optogalvanic spectrum of pure bromine discharge

Doppler limited laser optogalvanic (LOG) spectra are obtained by irradiating a bromine discharge with a cw dye laser. The discrete bands of the Br2B-X system appear superimposed on a strong continuum. The LOG spectrum is closely identical with the absorption/emission spectrum of Br2. Some extra bands and assigned in theB-X system are also observed and their vibrational quantum number assignment is given.

• Kelvin-Helmholtz instability in a rotating ideally conducting inhomogeneous plasma

The Kelvin-Helmholtz instability in sheared magnetohydrodynamic flow of an ideally conducting rotating inhomogeneous compressible plasma is investigated. The asymptotic behaviour inx of the Kelvin-Helmholtz eigenfunctions for the case of finite compressibility in the presence of rotation is discussed and instability condition is derived. In the incompressible limit, a dispersion relation is derived which has been solved numerically and discussed in detail. It is found that the inhomogeneous system is unstable in an incompressible plasma.

• Mass spectra and thermodynamic properties of some heavy and light mesons

An energy eigenvalue expression for a sextic anharmonic interaction potential is derived by solving the Schrödinger equation analytically within the framework of the Nikiforov–Uvarov (NU) method. The resultant expression is then used to calculate the mass spectra of some heavy and light mesons, viz., c$\bar{c}$, b$\bar{b}$ , b$\bar{c}$, c$\bar{s}$, b$\bar{s}$ and b$\bar{q}$, and the results are found to be in good agreement with the other theoretical and experimental studies. The energy eigenvalue expression is further used to compute some important thermodynamic quantities like partition function, specific heat capacity, free energy, mean energy, entropy and magnetisation.

• # Pramana – Journal of Physics

Volume 97, 2023
All articles
Continuous Article Publishing mode

• # Editorial Note on Continuous Article Publication

Posted on July 25, 2019