arXiv subjects

Bin Shao

Publications and source records attributed to Bin Shao.

79 records · Page 5Linked to original sources

arXiv1994

Classical and Quantum Coherent State Description of Nucleon-Antinucleon Annihilation at Rest in the Skyrme Model with Omega Mesons

We model the $N\bar{N}$ system at rest as a baryon number zero lump in the Skyrme model including the $ω$ field. We integrate the classical equations of motion from the highly non-perturbative annihilation region into the non-interacting radiation zone. Subsequent coherent state quantization of the radiation field gives a good description of the pion spectrum from annihilation at rest.

hep-ph↗

arXiv1994

Coherent state formulation of pion radiation from nucleon antinucleon annihilation

We assume that nucleon antinucleon annihilation is a fast process leading to a classical coherent pion pulse. We develop the quantum description of such pion waves based on the method of coherent states. We study the consequences of such a description for averages of charge types and moments of distributions of pion momenta with iso-spin and four-momentum conservation taken into account. We briefly discuss the applicability of our method to annihilation at rest, where we find agreement with experiment, and suggest other avenues for its use.

hep-ph↗

arXiv1993

Coherent Pion Radiation From Nucleon Antinucleon Annihilation

A unified picture of nucleon antinucleon annihilation into pions emerges from a classical description of the pion wave produced in annihilation and the subsequent quantization of that wave as a coherent state. When the constraints of energy-momentum and iso-spin conservation are imposed on the coherent state, the pion number distribution and charge ratios are found to be in excellent agreement with experiment.

nucl-th↗

arXiv1993

Study of the Three-Nucleon (e,e') Longitudinal Response Function with a New Approach

A new method for studying the many-body response functions is elaborated and first applied to the $^3$He longitudinal response. An integral transform of the response function is calculated from the bound-state-type equations for several versions of the N-N force. The equations are solved with the help of the hyperspherical expansion. The final-state interaction is completely taken into account. The results are compared with the integral transform of the experimental response function for 250 MeV/c$\leq q \leq 500$ MeV/c. The difference amounts to 20-25\% with the experimental response substantially exceeding the theoretical one in the low-energy region.

nucl-th↗

arXiv1993

The Skyrme model description of the spin-orbit force

We examine the derivation of the spin-orbit force from the Skyrme model. We find substantial agreement with phenomenological potentials. We show that a systematic and simultaneous treatment of all components of the kinetic energy introduces a minus sign relative to previous calculations for the iso-spin independent part of the interaction. We also explain the smallness of the iso-spin dependent part of the spin-orbit potential.

nucl-th↗

arXiv1993

Inertial parameters of the Skyrmion-Skyrmion system with the product ansatz

The kinetic energy of the Skyrmion-Skyrmion system is calculated in the product ansatz. The energy is expanded in a set of rotationally invariant quadratic functions of translational and iso-rotational velocities in the product ansatz and all inertial parameters are evaluated. Most of the iso-spin dependent parameters are small at separations larger than 1 fm. However, some parameters of the coupling between the iso-rotational velocities of the Skyrmions decay slowly, as $1/R$, when zero pion mass is used. Otherwise we find that the results are not sensitive to the addition of the pion mass term.

nucl-th↗

arXiv1992

Dynamics of antibaryon-baryon annihilation in the Skyrme model

We examine the dynamics of a baryon number zero lump in the Skyrme picture, as a model for annihilation in the $\bar{N}N$ system. We find that radiation propagates at the causal limit as a localized pulse and that the linearized theory gives a good approximation. Both of these results are contrary to findings in the Sine-Gordon model.

nucl-th↗