Hadronic production of a Higgs boson in association with two jets at ...

1.5. Higgs plus two jets: Its phenomenological role and an overview ofthis thesis 28The effective interaction linking gluons and scalar fields splits into a piece containingφ and the self-dual gluon field strengths and another part linking φ † to the anti-selfdualgluon field strengths. The last step conveniently embeds the Higgs interactionwithin the MHV structure of the QCD amplitudes. The self-duality of φ amplitudesalso results in them having a simpler structure than Higgs amplitudes. The fullHiggs amplitudes are then written as a sum of the φ (self-dual) and φ † (anti-selfdual)components,A (l)n (H; {p k }) = A (l)n (φ, {p k }) + A (l)n (φ † , {p k }). (1.61)We can also generate pseudo-scalar amplitudes from the difference of φ and φ †components,A n (l) (A; {p k }) = 1 (A(l)n (φ, {p k }) − A n (l) (φ † , {p k }) ) . (1.62)iFurthermore parity relates φ and φ † amplitudes,(∗A n (m) (φ† , g λ 11 , . . .,gλn n ) = A n (m) (φ, g−λ 11 , . . ., gn )) −λn . (1.63)From now on, we will only consider φ-amplitudes, knowing that all others can beobtained using eqs. (1.61)–(1.63). We will discuss tree amplitudes containing a φand partons in Appendix A.1.5 Higgs plus two jets: Its phenomenological roleand an overview of this thesisAs has been mentioned earlier in the chapter, an important search channel for theHiggs boson, in the mass range 115 < m H < 160 GeV, is production via weak bosonfusion [96]. A Higgs boson produced in this channel is expected to be producedrelatively centrally, in association with two hard forward jets. These striking kinematicfeatures are expected to enable a search for such events despite the otherwiseoverwhelming QCD backgrounds. Confidence in the theoretical prediction for theHiggs signal process is based upon knowledge of next-to-leading order corrections inboth QCD [97–99] and in the electroweak sector [100,101].