Non-perturbative chiral approach to Kp --gamma Y reactions

A recently developed nonperturbative chiral approach to describe the S=-1 meson-baryon reactions has been extended to investigate the near threshold $K^- p \to \gamma \Lambda, \gamma \Sigma^0$ reactions. With the parameters governed by chiral SU(3) symmetr

Non-perturbativechiralapproachtoK p→γYreactions

T.-S.H.Lee1,2,J.A.Oller1,E.Oset1andA.Ramos3

1DepartmentodeF´ sicaTe´oricaandIFIC,CentroMixtoUniversidaddeValencia-CSIC,46100

Burjassot(Valencia),Spain

2PhysicsDivision,ArgonneNationalLaboratory,Argonne,Illinois60439,USA

arXiv:nucl-th/9804053v2 11 Sep 19983Departmentd’EstructuraiConstituentsdelaMat`eria,UniversitatdeBarcelona,Diagonal647,08028Barcelona,Spain(February9,2008)AbstractArecentlydevelopednonperturbativechiralapproachtodescribetheS= 1meson-baryonreactionshasbeenextendedtoinvestigatethenearthresholdK p→γΛ,γΣ0reactions.WiththeparametersgovernedbychiralSU(3)symmetry,weshowthatthepredictedbranchingratiosΓK p→γΛ/ΓK p→allandΓK p→γΣ0/ΓK p→allareclosetotheexperimentalvalues.Thecouplingwiththeηchannels,whichwasshowntobeimportantintheS= 1meson-

baryonreactions,isalsofoundtobesigni canthere.Ourresultsareconsistent

withtheinterpretationoftheΛ(1405)asaquasi-boundmeson-baryonstate

asfoundinothersimilarchiralapproaches.

PACSNumbers:13.75.Jz,24.10.Eq,13.75.Lb,25.80.Nv

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