Suraj N. Gupta

Relativistic two-photon and two-gluon decay rates of heavy quarkonia

The decay rates of {ital c{bar c}} and {ital b{bar b}} through two-photon or two-gluon annihilations are obtained by using totally relativistic decay amplitudes and a sophisticated quantum-chromodynamic potential model for heavy quarkonia. Our results for the photonic and gluonic widths of the {sup 1}{ital S}{sub 0}, {sup 3}{ital P}{sub 0}, and the {sup 3}{ital P}{sub 2} states are in excellent agreement with the available experimental data. The procedures and mathematical techniques used by us for the treatment of the fermion-antifermion bound states are also applicable to other decay processes. {copyright} {ital 1996 The American Physical Society.}

Bc spectroscopy in a quantum-chromodynamic potential model.

We have investigated {ital B}{sub {ital c}} spectroscopy with the use of a quantum-chromodynamic potential model which was recently used by us for the light-heavy quarkonia. We give our predictions for the energy levels and the {ital E}1 transition widths. We also find, rather surprisingly, that although {ital B}{sub {ital c}} is not a light-heavy system, the heavy quark effective theory with the inclusion of the {ital m}{sub {ital b}}{sup -}{sup 1} and {ital m}{sub {ital b}}{sup -}{sup 1}ln{ital m}{sub {ital b}} corrections is as successful for {ital B}{sub {ital c}} as it is for {ital B} and {ital B}{sub {ital s}}. {copyright} {ital 1995 The American Physical Society.}

W, Z, and Higgs-boson scattering at SSC energies.

The scattering of [ital W], [ital Z], and Higgs bosons in the standard model is investigated in the region [ital s],[ital m][sub [ital H]][sup 2][much gt][ital m][sub [ital W]][sup 2] with no restrictions on the relative sizes of [ital s] and [ital m][sub [ital H]][sup 2], so that our results are applicable at energies below as well as above 2[ital m][sub [ital H]]. We have calculated, with the inclusion of the full one-loop corrections, the scattering matrix between the states [ital W][sub [ital L]][sup +][ital W][sub [ital L]][sup [minus]], [ital Z][sub [ital L]Z[ital L]], and [ital HH], and computed the [ital S]-wave amplitudes as functions of the center-of-mass energy [radical][ital s] for [ital m][sub [ital H]]=500 GeV and 1000 GeV. The apparent violation of unitarity is avoided by unitarizing the amplitudes by the [ital K]-matrix and the Pade methods. For the detection of the Higgs boson through gauge-boson scattering in [ital pp] collisions, we have used the unitarized amplitudes to obtain the invariant-mass distributions for the final [ital W][sub [ital L]][sup +][ital W][sub [ital L]][sup [minus]] and [ital Z][sub [ital L]Z[ital L]] pairs at the SSC energy of [radical][ital s] =40 TeV by means of the effective-[ital W] approximation.

Relativistic one-pion exchange nuclear potential

Abstract The exact relativistic one-pion exchange nuclear potential is derived in the centre-of-mass system, and the relationship between the relativistic potential and the Schrodinger equation is discussed.

Gauge-boson scattering signals at the CERN LHC.

We have extended our earlier treatment of the gauge-boson scattering with radiative corrections in the standard model at supercollider energies, and computed the rates for gauge-boson scattering modes in {ital pp} collisions leading to the final states {ital W}{sup +}{ital W}{sup {minus}}, {ital ZZ}(4{ital l}), {ital ZZ}(2{ital l}2{nu}), {ital W}{sup {plus_minus}}{ital Z}, and {ital W}{sup {plus_minus}}{ital W}{sup {plus_minus}}. Our results at the CERN LHC energy of {radical}{ital s}=14 TeV for {ital m}{sub {ital H}}=1000 GeV are compared with those recently obtained by Bagger {ital et} {ital al}. These results will be useful in the search for the Higgs bosons at supercollider energies as well as for experimentally distinguishing the standard model from nonminimal Higgs models. {copyright} {ital 1996 The American Physical Society.}

Particle-particle and particle-antiparticle interactions

Abstract A general method for the derivation of the particle-particle and particle-antiparticle interaction operators by methods of field theory is given, and it is applied to the electromagnetic electron-electron and electron-positon interactions as well as to the pionic proton-proton and proton-antiproton interactions.

Conformal Transformations and Space Travel

Conformal transformations are applied to the motion of a space ship experiencing a constant acceleration. The role of proper time is interpreted in terms of atomic periods, and the relationship between the conformal transformations and the general theory of relativity is clarified.

SU3 meson-baryon model with small symmetry-breaking interaction

Abstract It is shown by means of second-order calculations that the SU 3 model with small symmetry-breaking interaction leads to the difficulty of a negative intrinsic mass for baryons. It is concluded that Okubos derivation of the mass formulae cannot be regarded as satisfactory unless it is established that the higher-order effects are able to remove this difficulty.

Theory of mesons, baryons and resonances

Abstract A theory of mesons, baryons and resonances is developed in the three-dimensional isospace by assuming that the resonances should be expected to satisfy the same symmetry requirements as the elementary mesons and baryons. It is also assumed that the effective Lagrangian density for strong interactions should be invariant not only for arbitrary rotations of the axes in the isospace but also for simultaneous rotations of the axes in their complex planes. Besides the usual eight mesons and eight baryons, the formalism predicts the existence of additional particles and resonances with higher hypercharges and charges. In particular, the present theory is able to account for the singly charged particles with anomalous hypercharges observed in cosmic ray stars, and many of the resonances observed in meson-baryon interactions.

W, Z and Higgs Scattering at SSC Energies

The scattering of [ital W], [ital Z], and Higgs bosons in the standard model is investigated in the region [ital s],[ital m][sub [ital H]][sup 2][much gt][ital m][sub [ital W]][sup 2] with no restrictions on the relative sizes of [ital s] and [ital m][sub [ital H]][sup 2], so that our results are applicable at energies below as well as above 2[ital m][sub [ital H]]. We have calculated, with the inclusion of the full one-loop corrections, the scattering matrix between the states [ital W][sub [ital L]][sup +][ital W][sub [ital L]][sup [minus]], [ital Z][sub [ital L]Z[ital L]], and [ital HH], and computed the [ital S]-wave amplitudes as functions of the center-of-mass energy [radical][ital s] for [ital m][sub [ital H]]=500 GeV and 1000 GeV. The apparent violation of unitarity is avoided by unitarizing the amplitudes by the [ital K]-matrix and the Pade methods. For the detection of the Higgs boson through gauge-boson scattering in [ital pp] collisions, we have used the unitarized amplitudes to obtain the invariant-mass distributions for the final [ital W][sub [ital L]][sup +][ital W][sub [ital L]][sup [minus]] and [ital Z][sub [ital L]Z[ital L]] pairs at the SSC energy of [radical][ital s] =40 TeV by means of the effective-[ital W] approximation.