Status of High Energy Foward Elastic Scattering

Abstract

We present the results of fitting all data for $pp$ and $\bar pp$ scattering at $\sqrt s \geq 9.7$ Gev and up to the collider energy with various analytic parametrizations of the elastic forward scattering amplitudes based on the derivative dispersion relation. It is found that the model containing the Pomeron and Reggeon terms with 8 parameters has the most preferred $\chi^2/d.o.f = 1.3$, while the Donnachie and Landshoff model with 5 parameters has $\chi^2/d.o.f = 2.16$ for a data set of 111 experimental points. The current data however make no clear preference between the $\ell n s$ and $\ell n^2 s$ type Pomerons.