Artículos de revistas
Derivative dispersion relations above the physical threshold
Registro en:
Brazilian Journal of Physics. Sociedade Brasileira de Física, v. 37, n. 2a, p. 358-367, 2007.
0103-9733
S0103-97332007000300006
10.1590/S0103-97332007000300006
Autor
Ávila, R. F.
Menon, M. J.
Institución
Resumen
We discuss some formal and practical aspects related to the replacement of Integral Dispersion Relations (IDR) by derivative forms, without high-energy approximations. We first demonstrate that, for a class of functions with physical interest as forward scattering amplitudes, this replacement can be analytically performed, leading to novel Extended Derivative Dispersion Relations (EDDR), which, in principle, are valid for any energy above the physical threshold. We then verify the equivalence between the IDR and EDDR by means of a popular parametrization for total cross sections from proton-proton and antiproton-proton scattering and compare the results with those obtained through other representations for the derivative relations. Critical aspects on the limitations of the whole analysis, from both formal and practical points of view, are also discussed in some detail. 358 367