# Limited validity of West and Yennie integral formula for elastic scattering of hadrons

#### Abstract

The commonly used West and Yennie integral formula for the relative phase between the Coulomb and elastic hadronic amplitudes might be consistently applied to only if the hadronic amplitude had the constant ratio of the real to the imaginary parts at all kinematically allowed values of four momentum transfer squared. In our recent paper [1] we have pointed out that the integral formula of West and Yennie [2] describing the relative phase between the Coulomb and hadronic high-energy elastic scattering amplitudes may be applied only to the elastic hadronic amplitudes F(s, t) having the constant ratio between real and imaginary parts at all values of the four momentum transfer squared t; s being the value of the total CMS energy squared. As the given statement has not been explicitly proved it seemed for a series of colleagues as unreasoned. The corresponding reasoning will be, therefore, given in the following. West and Yennie [2] derived for the phase function αΦ(s, t) in the case of charged point-like nucleons (s ≫ m, m being nucleon mass) the formula αΦ(s, t) = ∓α [

### Cite this paper

@inproceedings{Kundrt2008LimitedVO, title={Limited validity of West and Yennie integral formula for elastic scattering of hadrons}, author={Vojtěch Kundr{\'a}t and Milo{\vs} Lokaj́ı{\vc}ek}, year={2008} }