Samirendra N. Biswas

Tests of second-class currents

Abstract We argue that the presence of second-class neutral currents can be tested from the observations of η→π 0 ν l ν l and electron polarisation in η→π0e+e-. Consequences of this model in η→π±e∓νe,τ±→ηπ±ντ and τ±→ωπ±ντ decays which would establish second-class charged currents are also discussed.

Symmetry breaking by deformations

The effects of symmetry breaking and renormalization on a unified field theory can be simulated by the use of a deformed gauge group instead of U(3). Here the use of a deformation of u(3) called uQ(3), with three independent parameters, is proposed and illustrated by obtaining a mass formula with electromagnetic mass splitting as well as the hypercharge and isospin dependence for the baryons.

Hannay angle for a classical spinning particle in a rotating magnetic field

For the spin-1 system in a slowly varying magnetic field, the authors investigate its classical analogue to calculate the Hannay angle and explicitly check that this is related to Berrys phase according to the well known semiclassical formula.

Quark matter core in neutron star

The possible phase transition to quark matter in a neutron star is considered using the neutron matter equation of state proposed recently by Canuto, Datta and Kalman (1978) which involves spin 2-meson interaction among nucleons. The corresponding equation of state for quark matter is taken from quantum chromodynamics. The Oppenheimer-Volkoff equation is then numerically solved to investigate the stability of a superdense system with quarkion cores.

Magnetic moment of relativistic quark gas in intense magnetic field

Magnetic properties of a system of noninteracting relativistic quark gas in presence of an external intense magnetic field has been calculated assuming that quarks obey parastatistics of order three. It is found, although the magnetization is greater for quark gas than that for normal hadronic system, it is unlikely that the spontaneous magnetization will take place in a quark star.

Magnetisation of quark gas in intense magnetic field

The magnetisation of a non-interacting quark gas in an intense magnetic field has been calculated assuming that the quarks obey parastatistics of order three. It is observed that magnetisation would attain larger values if quarks could obey parastatistics of higher order.

Study of scale invariance in a Bethe-Salpeter model

We study the scale invariance of the electroproduction structure functions W1(q2, ν) and νW2(q2, ν) in the limit q2 → ∞. Our model involves charged scalar particles φ, interacting minimally with the electromagnetic field and also with a massless scalar field χ via an interaction of the form g φ2χ. The forward Compton scattering amplitude is then studied in the ladder approximation with the ladder rungs made up of the particles χ. We obtain a non-trivial scaling law for νW2 but W1 goes to zero in the limit q2 → ∞.