Minijet veto: a tool for the heavy Higgs search at the LHC

Abstract

The distinct color flow of the $qq\to qqH,H\to W^{+}{W}^{-}$ process leads to suppressed radiation of soft gluons in the central region, a feature which is not shared by major background processes like $t\bar{t}$ production or $q\bar{q}\to W^{+}{W}^{-}$. For the leptonic decay of a heavy Higgs boson, $H\to W^{+}{W}^{-}\to {\ell }^{+}\hat{I}½{\ell }^{-}\bar{\hat{I}}½$, it is shown that these backgrounds are typically accompanied by minijet emission in the 20--40 GeV range. A central minijet veto thus constitutes a powerful background rejection tool. It may be regarded as a rapidity gap trigger at the semihard parton level which should work even at high luminosities.

18 pages, Revtex version 3 (can also run version 2). 3 postscript figures included (using uufiles). Compressed postscript version with figures available via anonymous ftp at ftp://phenom.physics.wisc.edu/pub/preprints/current/madph-94-856.ps.Z