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Mass and KLamda coupling of the N*(1535)
Physical Review Letters
|February 21, 2006
Summary
Researchers determined the coupling constant ratio for the N*(1535) resonance to kaon-Lambda and eta particles. This finding impacts the understanding of the N*(1535) resonance
Area of Science:
- Particle Physics
- Nuclear Physics
- Hadron Spectroscopy
Background:
- The N*(1535) is a nucleon resonance with implications for understanding hadron structure.
- Previous studies have established coupling constants for N*(1535) to eta mesons.
Purpose of the Study:
- To determine the coupling constant of the N*(1535) resonance to kaon-Lambda.
- To investigate the impact of this coupling on the N*(1535) resonance properties.
Main Methods:
- Utilized a resonance isobar model and an effective Lagrangian approach.
- Analyzed recent experimental data from BES on J/psi decays.
Main Results:
- Deduced the ratio of effective coupling constants gN*(1535)KLamda / gN*(1535)peta to be 1.3 ± 0.3.
- The calculated gN*(1535)KLamda reproduced near-threshold cross-section data for pp → pK+Lambda.
- The Breit-Wigner mass of N*(1535) was found to be approximately 1400 MeV when including the kaon-Lambda coupling.
Conclusions:
- The coupling of N*(1535) to kaon-Lambda is significant.
- The N*(1535) resonance mass is substantially lower than previously estimated when kaon-Lambda coupling is considered.
- This suggests a revised understanding of the nature of the N*(1535) resonance.
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