William B. Kilgore

Next-to-next-to-leading order Higgs production at hadron colliders

The Higgs-boson production cross section at pp and pp colliders is calculated in QCD at next-to-next-to-leading order (NNLO). We find that the perturbative expansion of the production cross section is well behaved and that scale dependence is reduced relative to the NLO result. These findings give us confidence in the reliability of the prediction. We also report an error in the NNLO correction to Drell-Yan production.

Higgs boson production in bottom quark fusion at next-to-next-to leading order

The total cross section for Higgs boson production in bottom-quark annihilation is evaluated at next-to-next-to-leading order in QCD. This is the first time that all terms at order

Infrared behavior of one-loop QCD amplitudes at next-to-next-to-leading order

{\ensuremath{\alpha}}_{s}^{2}

Production of a pseudo-scalar Higgs boson at hadron colliders at next-to-next-to-leading order

are taken into account. We find a greatly reduced scale dependence with respect to lower order results, for both the factorization and the renormalization scales. The behavior of the result is consistent with earlier determinations of the appropriate factorization scale for this process of

Production of a Higgs Boson Accompanied by Two Jets Via Gluon Fusion

{\ensuremath{\mu}}_{F}\ensuremath{\approx}{M}_{H}/4,

Soft and virtual corrections to pp -> H + X at NNLO

and supports the validity of the bottom parton density approach for computing the total inclusive rate. We present precise predictions for the cross section at the Fermilab Tevatron and the CERN Large Hadron Collider.

Higgs boson production at hadron colliders

We present universal factorization formulas describing the behavior of one-loop QCD amplitudes as external momenta become either soft or collinear. Our results are valid to all orders in the dimensional regularization parameter, {epsilon}. Terms through O({epsilon}{sup 2}) can contribute in infrared divergent phase space integrals associated with next-to-next-to-leading order jet cross sections. (c) 1999 The American Physical Society.

Subtraction terms for hadronic production processes at next-to-next-to-leading order

The production cross section for pseudo-scalar Higgs bosons at hadron colliders is computed at next-to-next-to-leading order (NNLO) in QCD. The pseudo-scalar Higgs is assumed to couple only to top quarks. The NNLO efiects are evaluated using an efiective lagrangian where the top quarks are integrated out. The NNLO corrections are similar in size to those found for scalar Higgs boson production.

Kinematical limits on Higgs boson production via gluon fusion in association with jets

Real emission corrections to gg ->H, which lead to H+2 jet events, are calculated at order alpha_s^4. Contributions include top-quark triangles, boxes and pentagon diagrams and are evaluated analytically for arbitrary top mass m_t. This new source of H+2 jet events is compared to the weak-boson fusion cross section for a range of Higgs boson masses. The heavy top-mass approximation appears to work well for intermediate Higgs-boson masses, provided that the transverse momenta of the final-state partons are smaller than the top-quark mass.

One-loop single-real-emission contributions to

The contributions of virtual corrections and soft gluon emission to the inclusive Higgs production cross section pp -> H + X are computed at next-to-next-to-leading order in the heavy top quark limit. We show that this part of the total cross section is well behaved in the sense of perturbative convergence, with the NNLO corrections amounting to an enhancement of the NLO cross section by \sim 5% for LHC and 10-20% for the Tevatron. We compare our results with an existing estimate of the full NNLO effects and argue that an analytic evaluation of the hard scattering contributions is needed.