skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Suppression of p-wave baryons in quark recombination

Abstract

We show that the observed suppression of the {lambda}(1520)/{lambda} ratio in central Au+Au collisions at the BNL Relativistic Heavy Ion Collider can be naturally understood in the constituent quark recombination model.

Authors:
;  [1];  [2]
  1. Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502 (Japan)
  2. (Japan) and Department of Physics, Duke University, Durham, North Carolina 27708 (United States)
Publication Date:
OSTI Identifier:
20864181
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 74; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevC.74.061901; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; BROOKHAVEN RHIC; GOLD 197 REACTIONS; GOLD 197 TARGET; LAMBDA-1520 BARYONS; P WAVES; QUARKS; RECOMBINATION

Citation Formats

Kanada-En'yo, Yoshiko, Mueller, Berndt, and Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502. Suppression of p-wave baryons in quark recombination. United States: N. p., 2006. Web. doi:10.1103/PHYSREVC.74.061901.
Kanada-En'yo, Yoshiko, Mueller, Berndt, & Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502. Suppression of p-wave baryons in quark recombination. United States. doi:10.1103/PHYSREVC.74.061901.
Kanada-En'yo, Yoshiko, Mueller, Berndt, and Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502. Fri . "Suppression of p-wave baryons in quark recombination". United States. doi:10.1103/PHYSREVC.74.061901.
@article{osti_20864181,
title = {Suppression of p-wave baryons in quark recombination},
author = {Kanada-En'yo, Yoshiko and Mueller, Berndt and Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502},
abstractNote = {We show that the observed suppression of the {lambda}(1520)/{lambda} ratio in central Au+Au collisions at the BNL Relativistic Heavy Ion Collider can be naturally understood in the constituent quark recombination model.},
doi = {10.1103/PHYSREVC.74.061901},
journal = {Physical Review. C, Nuclear Physics},
number = 6,
volume = 74,
place = {United States},
year = {Fri Dec 15 00:00:00 EST 2006},
month = {Fri Dec 15 00:00:00 EST 2006}
}
  • We study the strong interactions of the L=1 orbitally excited baryons with one heavy quark in the framework of the heavy hadron chiral perturbation theory. To leading order in the heavy mass expansion, the interaction Lagrangian describing the couplings of these states among themselves and with the ground state heavy baryons contains 45 unknown couplings. We derive sum rules analogous to the Adler-Weisberger sum rule which constrain these couplings and relate them to the couplings of the s-wave heavy baryons. Using a spin-3/2 baryon as a target, we find a sum rule expressing the deviation from the quark model predictionmore » for pion couplings to s-wave states in terms of couplings of the p-wave states. In the constituent quark model these couplings are related and can be expressed in terms of only six reduced matrix elements. Using recent CLEO data on {Sigma}{sub c}{sup {asterisk}} and {Lambda}{sub c1}{sup +} strong decays, we determine some of the unknown couplings in the chiral Lagrangian and two of the six quark model reduced matrix elements. Specific predictions are made for the decay properties of a few other L=1 charmed baryons. {copyright} {ital 1997} {ital The American Physical Society}« less
  • Masses of the various negative-parity baryons are calculated using a single consistent parameter set as described by Kalman and Hall. Reasonable fits to the masses of most of the ground-state and negative-parity baryons are obtained.
  • Masses of the various ground-state and P-wave baryons containing one b quark and u and d quarks are calculated using a parameter set developed for the noncharmed baryons. The sole additional parameter needed, m/sub b/, is obtained from a previous fit to phi, psi, and UPSILON systems using the same parameter set.
  • Masses of the various ground-state and negative-parity baryons containing one charmed quark are calculated using a parameter set developed for the noncharmed baryons. The sole additional parameter needed, m/sub c/, is obtained by fitting to the observed mass of ..lambda../sub c/(1/2)/sup +/. The resulting calculated value of the mass of ..sigma../sub c/(1/2)/sup +/ is in reasonable agreement with experimental values.
  • We discuss the spectrum and mixing angles of negative-parity baryons in a quark-model framework inspired by quantum chromodynamics. We take into account in zero order the removal of the degeneracy between the two P-wave states of the three-quark system in the S = - 1 sector, as well as the hyperfine interaction between quarks, but neglect spin-orbit coupling. We find good agreement with experiment in the S = 0 and S = - 1 sectors where there are data and predict the S = - 2, -3 sectors.