Form factors in the radiative pion decay

We perform an analysis of the form factors that rule the structure-dependent amplitude in radiative pion decay. The resonance contributions to pion -> e nu_e gamma decays are computed through the proper construction of the vector and axial-vector form factors by setting the QCD driven asymptotic...

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Detalles Bibliográficos
Autores: Mathieu, Vincent, Portolés, Jorge
Tipo de recurso: artículo
Fecha de publicación:2007
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/2736
Acceso en línea:http://hdl.handle.net/10261/2736
Access Level:acceso abierto
Palabra clave:QCD
Chiral lagrangians
Radiative pion decay
Descripción
Sumario:We perform an analysis of the form factors that rule the structure-dependent amplitude in radiative pion decay. The resonance contributions to pion -> e nu_e gamma decays are computed through the proper construction of the vector and axial-vector form factors by setting the QCD driven asymptotic properties of the three-point Green functions VVP and VAP, and by demanding the smoothening of the form factors at high transfer of momentum. A comparison between theoretical and experimental determination of the form factors is also carried out. We also consider and evaluate the role played by a non-standard tensor form factor. We conclude that, at present and due to the hadronic uncertainties, the search for new physics in this process is not feasible.