The evolution of the virtual photon-proton cross section with coherence length

Apr 12, 2016, 9:00 AM
SR4b (DESY Hamburg)


DESY Hamburg

Small-x, Diffraction and Vector Mesons WG5 Small-x and Diffraction


Allen Caldwell (Max Planck Institute)


Assuming the form $\sigma^{\gamma P} \propto l^{\lambda_{\rm eff}}$ at fixed $Q^2$ for the behavior of the virtual-photon proton scattering cross section, where $l$ is the coherence length of the photon fluctuations, it is seen that the extrapolated values of $\sigma^{\gamma P}$ for different $Q^2$ cross for $l\approx 10^8$~fm. It is argued that this behavior is not physical, and that the behavior of the cross sections must change before this coherence length $l$ is reached. The behavior is compared to expectations to expectations from various models.

Primary author

Allen Caldwell (Max Planck Institute)

Presentation materials