Mass and K{lambda} Coupling of the N*(1535)
Abstract
Using a resonance isobar model and an effective Lagrangian approach, from recent BES results on J/{psi}{yields}pp{eta} and {psi}{yields}pK{sup +}{lambda}, we deduce the ratio between effective coupling constants of N*(1535) to K{lambda} and p{eta} to be R{identical_to}g{sub N*(1535)K{lambda}}/g{sub N*(1535)p{eta}}=1.3{+}0.3. With the previous known value of g{sub N*(1535)p{eta}}, the obtained new value of g{sub N*(1535)K{lambda}} is shown to reproduce recent pp{yields}pK{sup +}{lambda} nearthreshold cross section data as well. Taking into account this large N*K{lambda} coupling in the coupled channel BreitWigner formula for the N*(1535), its BreitWigner mass is found to be around 1400 MeV, much smaller than the previous value of about 1535 MeV obtained without including its coupling to K{lambda}. The implication on the nature of N*(1535) is discussed.
 Authors:
 Institute of High Energy Physics, P.O. Box 918(4), Beijing 100049 (China)
 (China)
 CCAST (World Laboratory), P.O. Box 8730, Beijing 100080 (China)
 (4), Beijing 100049 (China)
 Publication Date:
 OSTI Identifier:
 20777006
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review Letters; Journal Volume: 96; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevLett.96.042002; (c) 2006 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; BREITWIGNER FORMULA; COUPLED CHANNEL THEORY; COUPLING CONSTANTS; CROSS SECTIONS; ETA MESONS; GEV RANGE 0110; HADRONIC PARTICLE DECAY; ISOBAR MODEL; J PSI3097 MESONS; KAONS PLUS; LAGRANGIAN FUNCTION; LAMBDA PARTICLES; MASS; N1535 BARYONS; PROTONPROTON INTERACTIONS
Citation Formats
Liu, B.C., Graduate School of the Chinese Academy of Sciences, Beijing 100049, Zou, B.S., and Institute of High Energy Physics, P.O. Box 918. Mass and K{lambda} Coupling of the N*(1535). United States: N. p., 2006.
Web. doi:10.1103/PhysRevLett.96.042002.
Liu, B.C., Graduate School of the Chinese Academy of Sciences, Beijing 100049, Zou, B.S., & Institute of High Energy Physics, P.O. Box 918. Mass and K{lambda} Coupling of the N*(1535). United States. doi:10.1103/PhysRevLett.96.042002.
Liu, B.C., Graduate School of the Chinese Academy of Sciences, Beijing 100049, Zou, B.S., and Institute of High Energy Physics, P.O. Box 918. Fri .
"Mass and K{lambda} Coupling of the N*(1535)". United States.
doi:10.1103/PhysRevLett.96.042002.
@article{osti_20777006,
title = {Mass and K{lambda} Coupling of the N*(1535)},
author = {Liu, B.C. and Graduate School of the Chinese Academy of Sciences, Beijing 100049 and Zou, B.S. and Institute of High Energy Physics, P.O. Box 918},
abstractNote = {Using a resonance isobar model and an effective Lagrangian approach, from recent BES results on J/{psi}{yields}pp{eta} and {psi}{yields}pK{sup +}{lambda}, we deduce the ratio between effective coupling constants of N*(1535) to K{lambda} and p{eta} to be R{identical_to}g{sub N*(1535)K{lambda}}/g{sub N*(1535)p{eta}}=1.3{+}0.3. With the previous known value of g{sub N*(1535)p{eta}}, the obtained new value of g{sub N*(1535)K{lambda}} is shown to reproduce recent pp{yields}pK{sup +}{lambda} nearthreshold cross section data as well. Taking into account this large N*K{lambda} coupling in the coupled channel BreitWigner formula for the N*(1535), its BreitWigner mass is found to be around 1400 MeV, much smaller than the previous value of about 1535 MeV obtained without including its coupling to K{lambda}. The implication on the nature of N*(1535) is discussed.},
doi = {10.1103/PhysRevLett.96.042002},
journal = {Physical Review Letters},
number = 4,
volume = 96,
place = {United States},
year = {Fri Feb 03 00:00:00 EST 2006},
month = {Fri Feb 03 00:00:00 EST 2006}
}

Role of the N*(1535) in the J/{psi}{yields}p{eta}p and J/{psi}{yields}pK{sup +}{lambda} reactions
We study the J/{psi}{yields}p{eta}p and J/{psi}{yields}pK{sup +}{lambda} reactions with a unitary chiral approach. We find that the unitary chiral approach, which generates the N*(1535) dynamically, can describe the data reasonably well, particularly the ratio of the integrated cross sections. This study provides further support for the unitary chiral description of the N*(1535). We also discuss some subtle differences between the coupling constants determined from the unitary chiral approach and those determined from phenomenological studies. 
Coupling constant for N*(1535)N{rho}
The value of the N*(1535)N{rho} coupling constant g{sub N*N{rho}} derived from the N*(1535){yields}N{rho}{yields}N{pi}{pi} decay is compared with that deduced from the radiative decay N*(1535){yields}N{gamma} using the vectormesondominance model. On the basis of an effective Lagrangian approach, we show that the values of g{sub N*N{rho}} extracted from the available experimental data on the two decays are consistent, though the error bars are rather large.