W hadroproduction at large transverse momentum beyond next-to-leading order

We study the production of W bosons at large transverse momentum in p pbar collisions. We show that the next-to-leading order cross section at large transverse momentum is dominated by threshold soft-gluon corrections. We add next-to-next-to-leading-order soft-gluon corrections to the exact next-to-leading-order differential cross sections. We find that these higher-order corrections provide modest enhancements to the transverse momentum distribution of the W at the Tevatron, and reduce significantly the dependence on the factorization and renormalization scales.Comment: 17 pages, 8 figure

Charged Higgs production via bg -> tH- at the LHC

I present a calculation of QCD radiative corrections to charged Higgs production via the process bg -> tH-. I show that the cross section is dominated by soft-gluon corrections, which are computed through next-to-next-to-leading order. Results for charged Higgs production at the LHC are presented, including the dependence of the cross section on the charged Higgs mass, the top quark mass, the factorization and renormalization scales, and tan beta.Comment: 11 pages, 8 figure

Top quark total and differential cross sections at NNLO and NNLL

I present recent NNLO-NNLL results for top quark hadroproduction at the Tevatron. The total cross section as well as transverse momentum and rapidity distributions are shown.Comment: 4 pages LaTeX, 2 figures; presented at DPF2000, to appear in the Proceeding

Single top quark production at the Tevatron: threshold resummation and finite-order soft gluon corrections

I present a calculation of threshold soft-gluon corrections to single top quark production in ppbar collisions via all partonic processes in the t and s channels and via associated top quark and W boson production. The soft-gluon corrections are formally resummed to all orders, and finite-order expansions of the resummed cross section are calculated through next-to-next-to-next-to-leading order (NNNLO) at next-to-leading logarithmic (NLL) accuracy. Numerical results for single top quark production at the Tevatron are presented, including the dependence of the cross sections on the top quark mass and on the factorization and renormalization scales. The threshold corrections in the t channel are small while in the s channel they are large and dominant. Associated tW production remains relatively minor due to the small leading-order cross section even though the K factors are large.Comment: 24 pages, 19 figures; some changes and additional results; uncertainty in t channel corrected; to appear in Phys. Rev.

Theoretical status of the top quark cross section

We discuss the most recent calculations of the top quark total cross section and transverse momentum distributions at the Tevatron and the LHC. These calculations include the soft-gluon corrections at next-to-next-to-leading order (NNLO). The soft NNLO corrections stabilize the scale dependence of the cross section.Comment: 4 pages, 2 figures, presented at DPF 2004, Riverside, California, August 26-31, 200

Understanding Bottom Production

We describe calculations of b b-bar production to next-to-next-to-leading order (NNLO) and next-to-next-to-leading logarithm (NNLL) near threshold in pp interactions. Our calculations are in good agreement with the b b-bar total cross section measured by HERA-B.Comment: contribution to the proceedings of Quark Matter'02, 4 pages, 1 .eps figure, uses special included style fil

Effects of Higher-Order Threshold Corrections in High-E_T Jet Production

Results for higher-order threshold enhancements in high-E_T jet production in hadron-hadron collisions are presented. Expressions are given for the next-to-next-to-leading order (NNLO) threshold corrections to the single-jet inclusive cross section at next-to-leading logarithmic (NLL) accuracy. The corrections are found to be small for the specific choice of E_T/2 for the factorization and renormalization scales, and the corrected cross section shows a substantial reduction of the scale dependence. A comparison to experimental results from the Tevatron is presented.Comment: 24 pages LaTeX, 5 figure

NNLL resummation for s-channel single top quark production

I present the next-to-next-to-leading-logarithm (NNLL) resummation of soft and collinear gluon corrections to single top quark production in the s channel. Attaining NNLL accuracy involves the calculation of the two-loop soft anomalous dimension for the partonic subprocesses. Finite-order expansions of the resummed cross section are calculated through next-to-next-to-leading order (NNLO). Numerical results are presented for s-channel single top quark production at the Tevatron and the LHC, including the dependence of the cross sections on the top quark mass and the uncertainties in the theoretical prediction. The higher-order corrections are significant for energies at both colliders and they decrease the theoretical uncertainty.Comment: 17 pages, 12 figures; added figures and discussio

Soft-gluon resummation for heavy quark production in hadronic collisions

We discuss the heavy quark production cross section near partonic threshold in hadronic collisions, including the resummation of leading and next-to-leading logarithms arising from soft gluon emission. We show how to handle the complications due to the non-universal non-leading logarithms. We give analytical results for the $q {\bar q}$ partonic subprocess and numerical results in the DIS scheme for top quark production at the Fermilab Tevatron where the $q {\bar q}$ channel dominates.Comment: 16 pages LaTeX including 4 eps figures, a few equations and some text added, figure 3 corrected, other small change

Next-to-next-to-next-to-leading-order soft-gluon corrections in hard-scattering processes near threshold

I present a unified calculation of soft-gluon corrections to hard-scattering cross sections through next-to-next-to-next-to-leading order (NNNLO). Master formulas are derived, from a threshold resummation formalism, that can be applied to total and differential cross sections for hard-scattering processes in hadron colliders. I also present numerical results for charged Higgs production at the LHC where these corrections are large, and for top quark production at the Tevatron where these corrections greatly reduce the scale dependence of the cross section.Comment: 22 pages, 3 figure