{lambda}NN and {sigma}NN systems at threshold
Abstract
We calculate the hypertriton binding energy and the {lambda}d and {sigma}d scattering lengths using baryonbaryon interactions obtained from a chiral constituent quark model. We study consistently the {lambda}NN and {sigma}NN systems by analyzing the effect of the {sigma}{r_reversible}{lambda} conversion. Our interactions correctly predict the hypertriton binding energy. The (I,J)=(0,3/2) {lambda}NN channel is also attractive and it might have a bound state. From the condition of nonexistence of a (0,3/2) {lambda}NN bound state, an upper limit for the spintriplet {lambda}N scattering length is obtained. We also present results for the elastic and inelastic {sigma}N and {lambda}N cross sections. The consistent description of the {sigma}N scattering cross sections imposes a lower limit for the corresponding spintriplet scattering lengths. In the {sigma}NN system the only attractive channels are (I,J)=(1,1/2) and (0,1/2), the (1,1/2) state being the most attractive one.
 Authors:
 Escuela Superior de Fisica y Matematicas, Instituto Politecnico Nacional, Edificio 9, 07738 Mexico D.F. (Mexico)
 (Spain)
 Departamento de Fisica Teorica e IFIC, Universidad de ValenciaCSIC, E46100 Burjassot, Valencia (Spain)
 Departamento de Fisica Fundamental, Universidad de Salamanca, E37008 Salamanca (Spain)
 Publication Date:
 OSTI Identifier:
 20995111
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevC.75.034002; (c) 2007 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; BINDING ENERGY; BOUND STATE; CHIRAL SYMMETRY; CHIRALITY; CROSS SECTIONS; DEUTERONS; HYPERNUCLEI; HYPERONS; NUCLEAR FORCES; NUCLEONHYPERON INTERACTIONS; QUARK MODEL; SCATTERING; SCATTERING LENGTHS; SPIN; TRIPLETS; TRITONS
Citation Formats
Garcilazo, H., Departamento de Fisica Fundamental, Universidad de Salamanca, E37008 Salamanca, FernandezCarames, T., and Valcarce, A.. {lambda}NN and {sigma}NN systems at threshold. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVC.75.034002.
Garcilazo, H., Departamento de Fisica Fundamental, Universidad de Salamanca, E37008 Salamanca, FernandezCarames, T., & Valcarce, A.. {lambda}NN and {sigma}NN systems at threshold. United States. doi:10.1103/PHYSREVC.75.034002.
Garcilazo, H., Departamento de Fisica Fundamental, Universidad de Salamanca, E37008 Salamanca, FernandezCarames, T., and Valcarce, A.. Thu .
"{lambda}NN and {sigma}NN systems at threshold". United States.
doi:10.1103/PHYSREVC.75.034002.
@article{osti_20995111,
title = {{lambda}NN and {sigma}NN systems at threshold},
author = {Garcilazo, H. and Departamento de Fisica Fundamental, Universidad de Salamanca, E37008 Salamanca and FernandezCarames, T. and Valcarce, A.},
abstractNote = {We calculate the hypertriton binding energy and the {lambda}d and {sigma}d scattering lengths using baryonbaryon interactions obtained from a chiral constituent quark model. We study consistently the {lambda}NN and {sigma}NN systems by analyzing the effect of the {sigma}{r_reversible}{lambda} conversion. Our interactions correctly predict the hypertriton binding energy. The (I,J)=(0,3/2) {lambda}NN channel is also attractive and it might have a bound state. From the condition of nonexistence of a (0,3/2) {lambda}NN bound state, an upper limit for the spintriplet {lambda}N scattering length is obtained. We also present results for the elastic and inelastic {sigma}N and {lambda}N cross sections. The consistent description of the {sigma}N scattering cross sections imposes a lower limit for the corresponding spintriplet scattering lengths. In the {sigma}NN system the only attractive channels are (I,J)=(1,1/2) and (0,1/2), the (1,1/2) state being the most attractive one.},
doi = {10.1103/PHYSREVC.75.034002},
journal = {Physical Review. C, Nuclear Physics},
number = 3,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}

Using the twobody interactions obtained from a chiral constituent quark model, we study all {lambda}NN and {sigma}NN states with I=0,1,2 and J=1/2,3/2 at threshold, taking into account all threebody configurations with S and D wave components. We constrain further the limits for the {lambda}N spintriplet scattering length a{sub 1/2,1}. Using the hypertriton binding energy, we find a narrow interval for the possible values of the {lambda}N spinsinglet scattering length a{sub 1/2,0}. We find that the {sigma}NN system has a quasibound state in the (I,J)=(1,1/2) channel very near threshold with a width of about 2.1 MeV.

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