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Title: Evidence for the Two-Pole Structure of the {lambda}(1405) Resonance

Abstract

The K{sup -}p{yields}{pi}{sup 0}{pi}{sup 0}{sigma}{sup 0} reaction is studied within a chiral unitary model. The distribution of {pi}{sup 0}{sigma}{sup 0} states forming the {lambda}(1405) shows, in agreement with a recent experiment, a peak at 1420 MeV and a relatively narrow width of {gamma}=38 MeV. The mechanism for the reaction is largely dominated by the emission of a {pi}{sup 0} prior to the K{sup -}p interaction leading to the {lambda}(1405). This ensures the coupling of the {lambda}(1405) to the K{sup -}p channel, thus maximizing the contribution of the second state found in chiral unitary theories, which is narrow and of higher energy than the nominal {lambda}(1405). This is unlike the {pi}{sup -}p{yields}K{sup 0}{pi}{sigma} reaction, which gives more weight to the pole at lower energy and with a larger width. The data of these two experiments, together with the present theoretical analysis, provide firm evidence of the two-pole structure of the {lambda}(1405)

Authors:
;  [1];  [2]
  1. Departamento de Fisica Teorica and IFIC, Centro Mixto, Institutos de Investigacion de Paterna-Universidad de Valencia-CSIC, Apartado correos 22085, 46071, Valencia (Spain)
  2. Departament d'Estructura i Constituents de la Materia, Universitat de Barcelona, Diagonal 647, 08028 Barcelona (Spain)
Publication Date:
OSTI Identifier:
20699253
Resource Type:
Journal Article
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 95; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevLett.95.052301; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0031-9007
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CHIRALITY; GEV RANGE 01-10; KAON-PROTON INTERACTIONS; KAONS MINUS; LAMBDA-1405 BARYONS; PION-PROTON INTERACTIONS; PIONS MINUS; PIONS NEUTRAL; SIGMA NEUTRAL PARTICLES

Citation Formats

Magas, V K, Oset, E, and Ramos, A. Evidence for the Two-Pole Structure of the {lambda}(1405) Resonance. United States: N. p., 2005. Web. doi:10.1103/PhysRevLett.95.052301.
Magas, V K, Oset, E, & Ramos, A. Evidence for the Two-Pole Structure of the {lambda}(1405) Resonance. United States. https://doi.org/10.1103/PhysRevLett.95.052301
Magas, V K, Oset, E, and Ramos, A. 2005. "Evidence for the Two-Pole Structure of the {lambda}(1405) Resonance". United States. https://doi.org/10.1103/PhysRevLett.95.052301.
@article{osti_20699253,
title = {Evidence for the Two-Pole Structure of the {lambda}(1405) Resonance},
author = {Magas, V K and Oset, E and Ramos, A},
abstractNote = {The K{sup -}p{yields}{pi}{sup 0}{pi}{sup 0}{sigma}{sup 0} reaction is studied within a chiral unitary model. The distribution of {pi}{sup 0}{sigma}{sup 0} states forming the {lambda}(1405) shows, in agreement with a recent experiment, a peak at 1420 MeV and a relatively narrow width of {gamma}=38 MeV. The mechanism for the reaction is largely dominated by the emission of a {pi}{sup 0} prior to the K{sup -}p interaction leading to the {lambda}(1405). This ensures the coupling of the {lambda}(1405) to the K{sup -}p channel, thus maximizing the contribution of the second state found in chiral unitary theories, which is narrow and of higher energy than the nominal {lambda}(1405). This is unlike the {pi}{sup -}p{yields}K{sup 0}{pi}{sigma} reaction, which gives more weight to the pole at lower energy and with a larger width. The data of these two experiments, together with the present theoretical analysis, provide firm evidence of the two-pole structure of the {lambda}(1405)},
doi = {10.1103/PhysRevLett.95.052301},
url = {https://www.osti.gov/biblio/20699253}, journal = {Physical Review Letters},
issn = {0031-9007},
number = 5,
volume = 95,
place = {United States},
year = {Fri Jul 29 00:00:00 EDT 2005},
month = {Fri Jul 29 00:00:00 EDT 2005}
}