122506983
Quark Effective Mass and Baryon Magnetic Moments
The magnetic moments of the octet baryons are now known experimentally to a good precision. The constituent quark model predicts f.L(p)/f.L(n) ratio and f.L(N) in excellent agreement,1) but the remaining hyperon moments show considerable discrepancy. Various attempts have been made to improve the situation by including effects such as symmetry breaking,2) configuration mixing,3) relativistic corrections,4) current quark picture,S) meson cloud contributions,6) anomalous moments,7) etc. However so far no attempt has succeeded in bridging the gap between theory and experiment. Recently Sogami and Oh'yamaguchi) have proposed an interesting prescription for the magnetic moments. They suggest that when a quark is probed by a soft photon, the effective mass of the quark (as observed by the photon) gets modified due to the quark interaction with spectator quarks inside the baryon. However, they obtain low value of f.L(J;+) and f.L(J;-). The f.L(S-) remains lower in magnitude than f.L(A). Moreover there are three parameters which they calculate though least.2) We wish to investigate the concept of effective mass with its possible mechanism. In this note we calculate the effective mass of the quark through its interaction with the spectator quarks by single gluon exchange. Then we use this effective mass to calculate the magnetic moments. All the parameters involved in the determination of the effective masses are obtained from the baryon masses. We find that our agreement with experiment is better than that of Sogami and Oh'yamaguchi.) The baryon mass is given by the sum of quark masses plus a spin dependent interaction,9)
122007970
Radiative weak decays of baryons
122629163
Higher Order Effects on Radiative Decays of Mesons
119573508
Weak Gamma Decays and the Nonleptonic Weak Hamiltonian
120063159
Weak nonleptonic decays of charm baryons emitting scalar mesons
We investigate the weak nonleptonic decays of charm baryons emitting scalar mesons employing the factorization scheme and predict their branching ratios.
120103541
Preliminary estimate of branching ratios of weak hadronic decays of bottom baryons emitting charmless scalar mesons
We give the first estimate of charmless scalar-meson emitting weak hadronic decays of $\varLambda _{b}^{0}$, $\varXi _{b}^{0}$ and $\varXi _{b}^{ -}$ bottom baryons employing the pole model and consequently predict their branching ratios.
118456219
Lepton textures and neutrino oscillations
A systematic analysis of the textures arising in lepton mass matrices have been carried out using unitary transformations and condition of naturalness for the Dirac and Majorana neutrino possibilities. It is observed that the recent three neutrino oscillation data together with the effective mass in neutrinoless double beta decay provide vital clues in predicting the general structures of these lepton mass matrices.
118676024
Generic lepton mass matrices and neutrino oscillations
Several intriguing aspects of neutrino oscillation phenomenology like the origin of small neutrino masses, the absolute neutrino mass scale, the neutrino mass hierarchy, i.e. normal or inverted and the nature of neutrinos, i.e. Dirac or Majorana, etc. have been addressed from a general perspective. We show how the fundamental considerations of unitary transformations, naturalness and seesaw mechanism suffices to determine the texture structure of fermion Yukawa couplings and discuss the significance of the effective mass in 0{\nu}{\beta}{\beta} decay for the texture structure of these couplings.