arXiv subjects

V. Gupta

Publications and source records attributed to V. Gupta.

43 records · Page 3Linked to original sources

arXiv2000

A new approach to the parametrization of the Cabibbo-Kobayashi-Maskawa matrix

The CKM-matrix V is written as a linear combination of the unit matrix I and a matrix U which causes intergenerational-mixing. It is shown that such a V results from a class of quark-mass matrices. The matrix U has to be hermitian and unitary and therefore can depend at most on 4 real parameters. The available data on the CKM-matrix including CP-violation can be reproduced by $V=(I+iU)/\sqrt{2}$. This is also true for the special case when U depends on \textit{only 2 real parameters}. There is no CP-violating phase in this parametrization. Also, for such a V the invariant phase $Φ\equiv ϕ_{12}+ϕ_{23}-ϕ_{13}$, satisfies a criterion suggested for `maximal' CP-violation.

hep-ph↗

arXiv1998

Identities involving elementary symmetric functions

A systematic procedure for generating certain identities involving elementary symmetric functions is proposed. These identities, as particular cases, lead to new identities for binomial and q-binomial coefficients.

math-ph↗

arXiv1998

Masses, Magnetic Moments, and Semileptonic Decays of Spin 1/2 Baryons with Sea Contribution

The spin 1/2 baryons are pictured as a composite system made out of a "core" of three valence quarks (as in the simple quark model) surrounded by a "sea" (of gluon and $q\bar{q}$ pairs) which is specified by its total quantum numbers. We assume the sea is a SU(3) flavor octet with spin 0 or 1 but no color. This model, considered earlier, is used to obtain simultaneous fits for masses, magnetic moments and $G_A/G_V$ for semileptonic decays. These fits give predictions for nucleon spin distributions in reasonable agreement with experiment.

hep-ph↗

arXiv1998

Semileptonic decays, magnetic moments and spin distributions of spin-1/2 baryons with sea contribution

Spin-1/2 baryons are considered as a composite system made out of a "core" of three quarks surrounded by a "sea" (of gluons and $q\bar{q}$-pairs) which is specified by its total quantum numbers. Specifically, we assume this sea to be a flavor octet with spin-0 or 1 but no color. We show our model can provide very goods fits to magnetic moments and semileptonic decay data using experimental errors. The predictions for spin distributions are in reasonable agreement with experiment.

hep-ph↗

arXiv1998

Scalar Sea Contributions to Spin 1/2 Baryon Structure and Magnetic Moments

We treat the baryon as a composite system made out of a "core" of three quarks (as in the standard quark model) surrounded by a "sea" (of gluons and $q\bar{q}$-pairs) which is specified by its total quantum numbers like flavor, spin and color. Specifically, we assume the sea to be a flavor octet with spin 0 but no color. The general wavefunction for spin 1/2 baryons with such a sea component is given and an application to the magnetic moments is considered. Numerical analysis shows that the scalar sea can provide a good fit to the magnetic moment data using experimental errors.

hep-ph↗

arXiv1996

Sea Contributions to Spin 1/2 Baryon Structure, Magnetic Moments, and Spin Distribution

We treat the baryon as a composite system made out of a \lq\lq core" of three quarks (as in the standard quark model) surrounded by a \lq\lq sea" (of gluons and $q\bar{q}$-pairs) which is specified by its total quantum numbers like flavor, spin and color. Specifically, we assume the sea to be a flavor octet with spin 0 or 1 but no color. The general wavefunction for spin 1/2 baryons with such a sea component is given. Application to the magnetic moments is considered. Numerical analysis shows that a scalar (spin 0) sea with an admixture of a vector (spin 1) sea can provide very good fits to the magnetic moment data {\em using experimental errors}. Our best fit automatically gives $g_A/g_V$ for neutron beta decay in agreement with data. This fit also gives reasonable values for the spin distributions of the proton and neutron.

hep-ph↗

arXiv1994

Sea Contributions and Nucleon Structure

We suggest a general formalism to treat a baryon as a composite system of three quarks and a `sea'. In this formalism, the sea is a cluster which can consists of gluons and quark-antiquark pairs. The hadron wave function with a sea component is given. The magnetic moments, related sum rules and axial weak coupling constants are obtained. The data seems to favor a vector sea rather than a scalar sea. The quark spin distributions in the nucleon are also discussed.

hep-ph↗