Space– and time–like electromagnetic form factors of the nucleon

R. Bijker*

Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Apartado Postal 70–543, 04510 México, D.F., México

* Invited talk at 'XXVIII Nuclear Physics Symposium', Cocoyoc, México, January 4–7, 2005.

Recibido el 27 de enero de 2005
Aceptado el 12 de marzo de 2005

Abstract

Recent experimental data on space– and time–like form factors of the nucleon are analyzed in terms of a two–component model with a quark–like intrinsic structure and a meson cloud. A good overall agreement is found for all electromagnetic form factors with the exception of the neutron magnetic form factor in the time–like region.

Keywords: Electromagnetic form factors; protons and neutrons.

Resumen

Se presenta el análisis de datos experimentales recientes de los factores de forma de espacio y tiempo del nucleón. Este análisis se realiza en términos de un modelo de dos componentes con una estructura intrínseca tipo quark y una nube masónica. Se obtuvo un buen acuerdo general para todos los factores de forma electromagnéticos con excepción del factor de forma magnético del neutrón en la región temporal.

Descriptores: Factores de forma electromagnéticos; protones y neutrones.

PACS: 13.40.Gp; 14.20.Dh

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Acknowledgments

This work was supported in part by Conacyt, Mexico. It is a pleasure to thank Franco Iachello and Kees de Jager for stimulating discussions.

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