https://doi.org/10.1140/epja/i2006-10408-x
PAVI 2006
Nucleon form factors and dispersion relations
Laboratori Nazionali di Frascati dell'INFN, Frascati, Italy
* e-mail: simone.pacetti@lnf.infn.it
Received:
31
August
2006
Accepted:
18
March
2007
Published online:
22
June
2007
We define a dispersive technique, based on data, analyticity and dispersion relations to handle the nucleon form factors. Two applications are explicitly considered. In the first case, we use the available theoretical and experimental information on the ratio between the electric and magnetic proton form factors, as inputs in the dispersive procedure that gives a complex description of this ratio in the whole q2 complex plane. In the second case, by inverting a dispersion relation and considering the data and the pQCD asymptotic behaviour as inputs, the magnetic nucleon form factors are reconstructed in their unphysical region. Resonances and phases in agreement with the expectations are found.
PACS: 13.40.Gp Electromagnetic form factors – / 11.55.Bq Analytic properties of S matrix – / 11.55.Fv Dispersion relations – / 13.66.Bc Hadron production in e - e + interactions –
© Società Italiana di Fisica and Springer-Verlag, 2007