The Higgs + jet channel at the LHC is sensitive to the effects of new physics both in the total rate and in the transverse momentum distribution at high p_T. We examine the production process using an effective field theory (EFT) language and discuss
the possibility of determining the nature of the underlying high scale physics from boosted Higgs production. The effects of heavy color triplet scalars and top partner fermions with TeV scale masses are considered as examples and Higgs-gluon couplings of dimension-5 and dimension-7 are included in the EFT. As a by-product of our study, we examine the region of validity of the EFT. Dimension-7 contributions in realistic new physics models give effects in the high p_T tail of the Higgs signal which are so tiny that they are likely to be unobservable.
We use an effective field theory (EFT) which includes all possible gluon-Higgs dimension-5 and dimension-7 operators to study Higgs boson plus jet production in next-to-leading order QCD. The EFT sheds light on the effect of a finite top quark mass a
s well as any Beyond-the-Standard Model (BSM) modifications of Higgs-gluon effective couplings. In the gluon channel, the accuracy of the heavy-top approximation for differential distributions arises from the non-interference between the helicity amplitudes of the G^3 h and G^2 h operators in the m_h < p_T limit at lowest order. One dimension-7 operator involving quark bilinears, however, contributes significantly at high p_T, and potentially offers a channel for seeing BSM effects. One-loop renormalization of these operators is determined, allowing resummation of large logarithms via renormalization group running. NLO numerical results at the LHC are presented, which include O(1/m_t^2) contributions in the SM limit.
The Higgs boson is produced at the LHC through gluon fusion at roughly the Standard Model rate. New colored fermions, which can contribute to $ggrightarrow h$, must have vector-like interactions in order not to be in conflict with the experimentally
measured rate. We examine the size of the corrections to single and double Higgs production from heavy vector-like fermions in $SU(2)_L$ singlets and doublets and search for regions of parameter space where double Higgs production is enhanced relative to the Standard Model prediction. We compare production rates and distributions for double Higgs production from gluon fusion using an exact calculation, the low energy theorem (LET), where the top quark and the heavy vector-like fermions are taken to be infinitely massive, and an effective theory (EFT) where top mass effects are included exactly and the effects of the heavy fermions are included to ${cal O}(1/M^2_X)$. Unlike the LET, the EFT gives an extremely accurate description of the kinematic distributions for double Higgs production.
