q-Deformation of the Krichever-Novikov Algebra

The recent focus on deformations of algebras called quantum algebras can be attributed to the fact that they appear to be the basic algebraic structures underlying an amazingly diverse set of physical situations. To date many interesting features of these algebras have been found and they are now known to belong to a class of algebras called Hopf algebras [1]. The remarkable aspect of these structures is that they can be regarded as deformations of the usual Lie algebras. Of late, there has been a considerable interest in the deformation of the Virasoro algebra and the underlying Heisenberg algebra [2-11]. In this letter we focus our attention on deforming generalizations of these algebras, namely the Krichever-Novikov (KN) algebra and its associated Heisenberg algebra.Comment: AmsTex. To appear in Letters in Mathematical Physic

Comparative study of magnetic and magnetotransport properties of Sm0.55Sr0.45MnO3 thin films grown on different substrates

Highly oriented polycrystalline SSMO thin films deposited on single crystal substrates by ultrasonic nebulized spray pyrolysis have been studied. The film on LAO is under compressive strain while LSAT and STO are under tensile strain. The presence of a metamagnetic state akin to cluster glass formed due to coexisting FM and antiferromagnetic/charge order (AFM/CO) clusters. All the films show colossal magnetoresistance but its temperature and magnetic field dependence are drastically different. In the lower temperature region the magnetic field dependent isothermal resistivity also shows signature of metamagnetic transitions. The observed results have been explained in terms of the variation of the relative fractions of the coexisting FM and AFM/CO phases as a function of the substrate induced strain and oxygen vacancy induced quenched disorder.Comment: 21 page

Symmetric Multiplets in Quantum Algebras

We consider a modified version of the coproduct for \U(\su_q(2)) and show that in the limit when $q \rightarrow 1$, there exists an essentially non-cocommutative coproduct. We study the implications of this non-cocommutativity for a system of two spin-$1/2$ particles. Here it is shown that, unlike the usual case, this non-trivial coproduct allows for symmetric and anti-symmetric states to be present in the multiplet. We surmise that our analysis could be related to the ferromagnetic and antiferromagnetic cases of the Heisenberg magnets.Comment: Needs subeqnarray.sty. To be published in Mod Phys Lett.

Recent status of the understanding of neutrino-nucleus cross section

In this work we have presented current understanding of neutrino-nucleon/nucleus cross sections in the few GeV energy region relevant for a precise determination of neutrino oscillation parameters and CP violation in the leptonic sector. In this energy region various processes like quasielastic and inelastic production of single and multipion production, coherent pion production, kaon, eta, hyperon production, associated particle production as well as deep inelastic scattering processes contribute to the neutrino event rates.Comment: 9-Pages, 4-figures, Talk given at DAE-HEP Symposium held at Delhi University, 12-16 December, 201