Elastic proton-proton collisions at high energies

Under the influence of standardly used (however, very simplified) description of Coulomb-hadronic interference proposed by West and Yennie (1968) the protons have been interpreted as “transparent” objects; elastic collisions have been interpreted as more central than inelastic ones. This property may be hardly put in agreement with the fact that in the majority of hadronic collisions many different particles have been created at high energies. Using the more general eikonal model it will be shown that the protons may be interpreted in agreement with usual conception; elastic processes being more peripheral than inelastic ones. The contemporary TOTEM experiment at the LHC accelerator in CERN devoted to measurement of elastic pp scattering and diffractive processes at the highest ever reached energies will be described. The eikonal model will be explained to greater details, generalized and applied to experimental data of elastic pp collisions under different assumptions at 52.8 GeV (older ISR data measured at CERN) and also at much higher energy of 8 TeV (new TOTEM data). The impact of different assumptions on determination of several quantities specifying hadron interaction will be studied. Mainly the assumptions influencing behaviour of elastic collisions in dependence on impact parameter of colliding protons will be discussed.