2010/12/31 by Carola F. Berger, Claudio Marcantonini, Iain W. Stewart +2 · 1 citation
Physics and Astronomy · #hep-ph #hep-ex #nucl-th
paper · pdf · doi:10.1007/jhep04(2011)092
38 pages + appendices, 21 figures, v2: extended discussion section, added figure with individual scale variations, journal version
arxiv created 2011/04/09 · arxiv updated 2015/05/20
A major ingredient in Higgs searches at the Tevatron and LHC is the elimination of backgrounds with jets. In current H -> WW -> lnulnu searches, jet algorithms are used to veto central jets to obtain a 0-jet sample, which is then analyzed to discover the Higgs signal. Imposing this tight jet veto induces large double logarithms which significantly modify the Higgs production cross section. These jet-veto logarithms are presently only accounted for at fixed order or with the leading-logarithmic summation from parton-shower Monte Carlos. Here we consider Higgs production with an inclusive event-shape variable for the jet veto, namely beam thrust Taucm, which has a close correspondence with a traditional pT jet veto. Taucm allows us to systematically sum the large jet-veto logarithms to higher orders and to provide better estimates for theoretical uncertainties. We present results for the 0-jet Higgs production cross section from gluon fusion at next-to-next-to-leading-logarithmic order (NNLL), fully incorporating fixed-order results at next-to-next-to-leading order (NNLO). At this order the scale uncertainty is 15-20%, depending on the cut, implying that a larger scale uncertainty should be used in current Tevatron bounds on the Higgs.