Abstract

Several key processes at the LHC in the standard model and beyond involve bottom quarks: single-top, Higgs, and weak vector boson associated production. They can be described in QCD either in a 4-flavor or 5-flavor scheme. In the former, bottom quarks appear only in the final state and are typically considered massive final state particles. In 5-flavor schemes, calculations include bottom quarks in the initial state, they are simpler and allow the resummation of possibly large initial state logarithms of the type log(Q/mb) into the bottom parton distribution function (PDF), Q being the typical scale of the hard process. An analogous classification can be applied to processes involving bottom quarks in the final state, in which the b fragmentation acts like the b PDF . In this talk, I describe a method for assessing the impact of resummation of collinear logarithms and provide an explanation of why and how a substantial agreement between total cross sections can be obtained in the two schemes. I will describe the recent results concerning the production of a heavy charged Higgs boson at the LHC . Finally I discuss several generalizations of the proposed prescription and future perspectives.