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Title: Heavy baryons in the Skyrme model: The role of highly anharmonic collective motion

Abstract

In the heavy quark and large N{sub c} limits, ordinary (exotic) heavy baryons can be considered as bound states of heavy mesons (antimesons) and chiral solitons. In these limits, the heavy mesons (or antimesons) and the chiral solitons are extremely heavy and are presumed to fall to the bottom of the effective potential. Previous studies have approximated the effective potential as harmonic about the minimum. However, when realistic masses for the heavy meson and chiral soliton are considered, longer range parts of the effective potential can become relevant. In this paper, we show that these longer-ranged effects yield effective wave functions which are qualitatively very different from those expected from the combined large N{sub c} and heavy quark limits. These potentials can support bound heavy pentaquarks under some conditions. The consequence of these new energy states and wave functions on the Isgur-Wise function for the semileptonic decay of heavy baryons is also considered.

Authors:
;  [1]
  1. Department of Physics, University of Maryland, College Park, Maryland 20742-4111 (United States)
Publication Date:
OSTI Identifier:
21020479
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 9; Other Information: DOI: 10.1103/PhysRevD.75.094007; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ANTIMESONS; B QUARKS; BARYONS; BOUND STATE; C QUARKS; CHIRALITY; REST MASS; SEMILEPTONIC DECAY; SKYRME POTENTIAL; SOLITONS; T QUARKS; WAVE FUNCTIONS

Citation Formats

Cohen, Thomas D., and Hohler, Paul M. Heavy baryons in the Skyrme model: The role of highly anharmonic collective motion. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.094007.
Cohen, Thomas D., & Hohler, Paul M. Heavy baryons in the Skyrme model: The role of highly anharmonic collective motion. United States. doi:10.1103/PHYSREVD.75.094007.
Cohen, Thomas D., and Hohler, Paul M. Tue . "Heavy baryons in the Skyrme model: The role of highly anharmonic collective motion". United States. doi:10.1103/PHYSREVD.75.094007.
@article{osti_21020479,
title = {Heavy baryons in the Skyrme model: The role of highly anharmonic collective motion},
author = {Cohen, Thomas D. and Hohler, Paul M.},
abstractNote = {In the heavy quark and large N{sub c} limits, ordinary (exotic) heavy baryons can be considered as bound states of heavy mesons (antimesons) and chiral solitons. In these limits, the heavy mesons (or antimesons) and the chiral solitons are extremely heavy and are presumed to fall to the bottom of the effective potential. Previous studies have approximated the effective potential as harmonic about the minimum. However, when realistic masses for the heavy meson and chiral soliton are considered, longer range parts of the effective potential can become relevant. In this paper, we show that these longer-ranged effects yield effective wave functions which are qualitatively very different from those expected from the combined large N{sub c} and heavy quark limits. These potentials can support bound heavy pentaquarks under some conditions. The consequence of these new energy states and wave functions on the Isgur-Wise function for the semileptonic decay of heavy baryons is also considered.},
doi = {10.1103/PHYSREVD.75.094007},
journal = {Physical Review. D, Particles Fields},
number = 9,
volume = 75,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}
  • We obtain the spectra of excited heavy baryons containing one heavy quark by quantizing the exactly solved heavy meson bound states to the Skyrme soliton. The results are comparable to the recent experimental observations and quark model predictions, and are consistent with heavy quark spin symmetry. However, the somewhat large dependence of the results on the heavy quark mass strongly calls for the incorporation of the soliton-recoil effects. {copyright} {ital 1996 The American Physical Society.}
  • We derive large-amplitude collective equations of motion from the variational principle for the time-dependent Schr{umlt o}dinger equation. These equations reduce to the well-known diabatic formulas for vibrational frequencies in the small-amplitude limit. The finite-amplitude expression allows departures from the harmonic behavior of giant resonances to be simply estimated. The relative shift of the second phonon falls with nuclear mass A as A{sup {minus}4/3} in the three modes we consider: monopole, dipole, and quadrupole. Numerically, the effect is very small in heavy nuclei, as was found with other approaches. {copyright} {ital 1997} {ital The American Physical Society}
  • We calculate the complete order 1/[ital N] corrections to baryon masses in the rigid rotator approach to the three-flavor Skyrme model.
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