Importance of Sea Contribution to Nucleons

We studied the statistical model of nucleons consisting of sea having various quark-gluon Fock states in addition to valence quarks. Using statistical consideration and taking 86% of the total Fock states contributing to the low energy properties of nucleon, we aim to find the contributions to these properties coming from the scalar, vector and tensor sea. We checked its validity against the assumption where the contributions from scalar and tensor sea have been suppressed and justified to be unimportant. We took the approximation that sea is getting a zero contribution from H_0 G_\bar10 and H_1 G_\bar10 in three gluon states. Under above considerations, the calculated magnetic moment, spin distribution and weak decay coupling constant ratio for proton and neutron states have been tabulated. We hereby confirm that the suppression of the scalar and tensor sea leads to modification in the parameters of the nucleons showing deviation from the experimental data.Comment: 13 pages, 5 figures, To be published in NP

Masses and Strong Decay properties of Radially Excited Bottom states B(2S)and B(2P) with their Strange Partners Bs(2S) and Bs(2P)

In this paper, we analyzed the experimentally available radially excited charm mesons to predict the similar spectra for the n=2 bottom mesons. In the heavy quark effective theory, we explore the flavor independent parameters to calculate the masses for the experimentally unknown n=2 bottom mesons B(2S), B(2P), Bs(2S) and Bs(2P). We have also analyzed these bottom masses by applying the QCD and 1/mQ corrections to the lagrangian leading to the modification of flavor symmetry parameters as. Further strong decay widths are determined using these calculated masses to check the sensitivity of these corrections for these radially excited mesons. The calculated decay widths are in the form of strong coupling constant geHH, egSH and egTH. We concluded that these corrections are less sensitive for n=2 masses as compared to n=1 masses. Branching ratios and branching fractions of these states are calculated to have a deeper understanding of these states. These predicted values can be confronted with the future experimental data.Comment: 11 Pages, 6 Table

Finite BRST Mapping in Higher Derivative Models

We continue the study of finite field dependent BRST (FFBRST) symmetry in the quantum theory of gauge fields. An expression for the Jacobian of path integral measure is presented, depending on a finite field-dependent parameter, and the FFBRST symmetry is then applied to a number of well-established quantum gauge theories in a form which includes higher-derivative terms. Specifically, we examine the corresponding versions of the Maxwell theory, non-Abelian vector field theory, and gravitation theory. We present a systematic mapping between different forms of gauge-fixing, including those with higher-derivative terms, for which these theories have better renormalization properties. In doing so, we also provide the independence of the S-matrix from a particular gauge-fixing with higher derivatives. Following this method, a higher-derivative quantum action can be constructed for any gauge theory in the FFBRST framework.Comment: 9 pages, published in Braz. J. Phy

Status of reaction theory for studying rare isotopes

Reactions are an important tool to study nuclear structure and for extracting reactions relevant for astrophysics. In this paper we focus on deuteron induced reactions which can provide information on neutron shell evolution as well as neutron capture cross sections. We review recent work on the systematic comparison of the continuum discretized coupled channel method, the adiabatic wave approximation and the Faddeev momentum-space approach. We also explore other aspects of the reaction mechanism and discuss in detail difficulties encountered in the calculations.Comment: 7 pages, 5 figures, proceeding for HITES 201