QCD analysis of neutral and charged current cross sections and search for contact interactions at HERA

A QCD analysis of the inclusive deep inelastic ep scattering cross section measured by the H1 experiment at HERA is presented. The data correspond to a total integrated luminosity of about 0.5 fb-1 and covers a kinematic range of 0.5 GeV2 - 30000 GeV2 in the negative four-momentum transfer Q2 and 3 . 10-5 - 0.65 in Bjorken x. The performed QCD analysis of the double differential neutral and charged current cross sections results in a set of parton distribution functions H1PDF 2012. The precise data from HERA II period in the kinematic region of high Q2 considerably improve the accuracy of the PDFs at the high x. In addition a search for signs of new physics using single differential neutral current cross section measurements at high Q2 is performed. The observed good agreement of the analysed data with the Standard Model predictions allows to set constraints on various new physics models within the framework of contact interactions. Limits are derived on the compositeness scale for general contact interactions, on the ratio of mass to the Yukawa coupling for heavy leptoquark models, on the effective Plank-mass scale in the large extra dimension models and on the quark radius.