15718192
A new class of Inhomogeneous string cosmological models in general relativity
Abstract
A new class of solutions of Einstein field equations has been investigated for inhomogeneous cylindrically symmetric space-time with string source. To get the deterministic solution, it has been assumed that the expansion (θ) in the model is proportional to the eigen value σ1  1 of the shear tensor σi  j. Certain physical and geometric properties of the models are also discussed.

122331597
Some Anisotropic Homogeneous Cosmological Models in Self-creation Cosmology
The paper presents an exact solution of cylindrically symmetric cosmological models which are of Petrov type-I or Petov type-D in Barber’s second self-creation theory of gravitation. Some physical and geometrical properties of these models are also discussed.
120331693
Bianchi Type-I Cosmological Model Filled with Viscous Fluid in a Modified Brans-Dicke Cosmology
Adding the cosmological term, which is assumed to be variable in Brans-Dicke theory we have discussed about a Bianchi type-I cosmological model filled with viscous fluid with free gravitational field of Petrov type-D. The effect of viscousity on various kinematical parameters has been discussed. Finally, this model has been transformed to the original form (1961) of Brans-Dicke theory including a variable cosmological term.
118562891
Constraints on Non-Commutative Physics Scale with Neutrino-Electron Scattering
Neutrino-electron scatterings ($\ensuremath{\nu}\ensuremath{-}e$) are purely leptonic processes with robust standard model predictions. Their measurements can therefore provide constraints to physics beyond the standard model. Noncommutative (NC) field theories modify space-time commutation relations, and allow neutrino electromagnetic couplings at the tree level. Their contribution to the neutrino-electron scattering cross section was derived. Constraints were placed on the NC scale parameter ${\ensuremath{\Lambda}}_{\mathrm{NC}}$ from $\ensuremath{\nu}\ensuremath{-}e$ experiments with reactor and accelerator neutrinos. The most stringent limit of ${\ensuremath{\Lambda}}_{\mathrm{NC}}g3.3\text{ }\text{ }\mathrm{TeV}$ at 95% confidence level improves over the direct bounds from collider experiments.
119113588
Study of Radioactive Impurities in Neutron Transmutation Doped Germanium
A program to develop low temperature (mK) sensors with neutron transmutation doped Ge for rare event studies with a cryogenic bolometer has been initiated. For this purpose, semiconductor grade Ge wafers are irradiated with thermal neutron flux from Dhruva reactor at Bhabha Atomic Research Centre (BARC), Mumbai. Spectroscopic studies of irradiated samples have revealed that the environment of the capsule used for irradiating the sample leads to significant levels of 65 Zn, 110m Ag and 182 Ta impurities, which can be reduced by chemical etching of approximately � 50 µm thick surface layer. From measurements of the etched samples in the low background counting setup, activity due to trace impurities of 123 Sb in bulk Ge is estimated to be � 1 Bq/g after irradiation. These estimates indicate that in order to use the NTD Ge sensors for rare event studies, a cooldown period of � 2 years would be necessary to reduce the radioactive background to � 1 mBq/g.
123264743
Rigorous sum rules and bounds on pion-pion scattering lengths
Abstract We deduce from axiomatic field theory rigorous sum rules, and upper and lower bounds on S-and P-wave ππ scattering lenghts in terms of physical region forward ππ amplitudes, and also absolute sum rule inequalities on those amplitudes involving pion mass alone.
120319641
Fractionally-charged atomic systems and the Stanford quark-search experiments
Abstract The binding energies for the one- and two-electron systems (fe−), (fe−e−), (ffe−) and (ffe−e−) containing fractionally-charged objects f are calculated. Results are given for the fractional-charge values 1 3 , 2 3 and 4 3 . A possible explanation of the experimental results of the Stanford group is given in terms of these. Our results seem to prefer the value 2 3 suggesting that one of the possibilities for f is that is might be a liberated u-quark.
119834941
Analytic continued fraction theory for a class of confinement potentials
We study a general class of confinement potentials in Schrödinger theory using the analytic theory of continued fractions. We construct an infinite continued fraction representation for the Green's function and study its convergence, its analytic properties in the major coupling constant and its relation to the perturbation series. We prove the existence of normalizable confined state eigensolutions with equally spaced energy levels if certain constraints on the coupling constants of the theory are satisfied: we also show that under a separate set of constraints neither bound nor confined states exist.