PDF Fits at HERA

Abstract

The HERAPDF1.0 PDF set, which was an NLO QCD analysis based on H1 and ZEUS combined inclusive cross section data from HERA-I, has been updated to HERAPDF1.5 by including preliminary inclusive cross section data from HERA-II running. Studies have also been made by adding various other HERA data sets: combined charm data, combined low energy run data and H1 and ZEUS jet data. These data give information on the treatment of charm and the charm quark mass and on the value of ${\alpha }_s(M_Z)$. The PDF analysis has also been extended to NNLO. The PDFs give a good description of Tevatron and early LHC data.

Comments: On behalf of ZEUS and H1 collaborations, 6 pages, 6 figures. To appear in the Proceedings of the 2011 Europhysics Conference on High Energy Physics, HEP 2011, July 2011, Grenoble, France