When hadrons become unstable: a novel type of non-analyticity in chiral extrapolations.

Hadron masses show a specific dependence on the quark masses. Therefore, the variation of these masses can cause a resonance in a hadronic scattering amplitude to become a bound state. Consequently, the amplitude exhibits a non analytic behavior at this transition. Crossed amplitudes, where the reso...

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Detalles Bibliográficos
Autores: Llanes Estrada, Felipe José, Guo, F.-K, Hanhart, C, Meißner, U.-G
Tipo de recurso: artículo
Fecha de publicación:2011
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/43937
Acceso en línea:https://hdl.handle.net/20.500.14352/43937
Access Level:acceso abierto
Palabra clave:53
Quark-Mass Dependence
Vector Form-Factor
Perturbation-Theory
Pion
Qcd
Lattice
Física (Física)
22 Física
Descripción
Sumario:Hadron masses show a specific dependence on the quark masses. Therefore, the variation of these masses can cause a resonance in a hadronic scattering amplitude to become a bound state. Consequently, the amplitude exhibits a non analytic behavior at this transition. Crossed amplitudes, where the resonance can be exchanged in the t-channel, can be shown to exhibit the same phenomenon by s --> t analytic continuation. This entails possible kinks in lattice quark-mass extrapolations needed to compute hadronic observables.