Shedding light on the gluon: From LHC towards a future EIC (with a short introduction to high energy scattering)

Martin Hentschinski (U. de las Américas, Puebla)

RESUMEN: In this talk we give an overview over several recent result in the exploration of the gluon at low values of Bjorken x. In a first part of the talk we give an overview of the theoretical framework that underlies the description in this kinematical limit of perturbative QCD and gauge theories in general. In the second part we present the results of a recent analysis of photo-production of vector mesons J/Psi and Upsilon measured both at HERA and LHC using perturbative low x evolution. We find that the growth of the low density evolution is too strong to describe data, if one does not use unnaturally high next-to-leading order corrections. We interpret this observation as a sign for gluon saturation.