Physics Commons^™

Soft-Gluon Corrections To Hard-Scattering Cross Sections Through Nnnlo, Nikolaos Kidonakis

Faculty and Research Publications

I present a systematic approach to calculating soft-gluon corrections through next-to-next-to-nextto-leading order for arbitrary hard-scattering cross sections. Using a unified approach, master formulas are derived for processes with both simple and complex color flows. Applications and numerical results are given for some processes of interest, including charged Higgs production and top quark production in the Standard Model and beyond.

W Production At Large Transverse Momentum At The Large Hadron Collider, Richard J. Gonsalves, Nikolaos Kidonakis, Agustín Sabio Vera

Faculty and Research Publications

We study the production of W bosons at large transverse momentum in pp collisions at the Large Hadron Collider (LHC). We calculate the complete next-to-leading order (NLO) corrections to the differential cross section. We find that the NLO corrections provide a large increase to the cross section but, surprisingly, do not reduce the scale dependence relative to leading order (LO). We also calculate next-to-next-to-leading-order (NNLO) soft-gluon corrections and find that, although they are small, they significantly reduce the scale dependence thus providing a more stable theoretical prediction.

Soft-Gluon Expansions Through Nnnlo, Nikolaos Kidonakis

Faculty and Research Publications

I present universal master formulas for soft-gluon corrections to hard-scattering cross sections through next-to-next-to-next-to-leading order (NNNLO). I also briefly discuss applications to some processes where these corrections enhance the cross section and decrease the scale dependence.

Theoretical Status Of The Top Quark Cross Section, Nikolaos Kidonakis, Ramona Vogt

Faculty and Research Publications

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.

Collinear And Soft Resummation In The Large-X Limit, Nikolaos Kidonakis

Faculty and Research Publications

I discuss general unified formulas for resumming collinear and soft contributions to QCD hard scattering cross sections at laxge x. Expansions of the resummed cross sections to next-to-next-to-next-to-leading order are also shown along with applications of the formalism.

Large-Qt W-Boson Production At The Tevatron, Nikolaos Kidonakis, Agustín Sabio Vera

Faculty and Research Publications

The production of W bosons at large transverse momentum at the Tevatron is dominated by soft-gluon corrections. In this talk we present a calculation of these corrections at next-to-next-to-leading order. The corrections enhance the transverse momentum distribution of the W while reducing the scale dependence.

Read More: http://www.worldscientific.com/doi/abs/10.1142/S0217751X05026236

Top Quark And Charged Higgs Production At Hadron Colliders, Nikolaos Kidonakis

Faculty and Research Publications

I present a brief theoretical update on top quark pair production at the Tevatron and give values of the NNLO-NNNLL cross section for both m_t=175 and 178 GeV. I then present a calculation of the cross section for charged Higgs production in association with a top quark at the LHC, including NNLO soft-gluon corrections.

Evidence For A Weak Galactic Center Magnetic Field From Diffuse Low Frequency Nonthermal Radio Emission, Ted N. Larosa, C. L. Brogan, S. N. Shore, T. J. Lazio, N. E. Kassim, M. E. Nord

Faculty and Research Publications

New low-frequency 74 and 330 MHz observations of the Galactic center (GC) region reveal the presence of a large-scale (6° × 2°) diffuse source of nonthermal synchrotron emission. A minimum-energy analysis of this emission yields a total energy of ~(4/7f3/7) × 1052 ergs and a magnetic field strength of ~6(/f)2/7 μG (where is the proton to electron energy ratio and f is the filling factor of the synchrotron emitting gas). The equipartition particle energy density is 1.2(/f)2/7 eV cm-3, a value consistent with cosmic-ray data. However, the derived magnetic field is several orders of …

Charged Higgs Production Via Bg -> Th(-) At The Lhc, Nikolaos Kidonakis

Faculty and Research Publications

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.

Sectorial Convergence Of U-Statistics, Anda Gadidov

Faculty and Research Publications

In this note we show that almost sure convergence to zero of symmetrized U-statistics indexed by a linear sector in ℤ^d₊ is equivalent to convergence along the diagonal of ℤ^d₊, as it is considered in Latała and Zinn [Ann. Probab. 28 (2000) 1908–1924]. Comparisons with similar results for sums of multi-indexed i.i.d. random variables are also made.

Charged Higgs Production: Higher-Order Corrections, Nikolaos Kidonakis

Faculty and Research Publications

I present a calculation of higher-order radiative corrections to charged Higgs production in association with a top quark via the process bg -> tH-. 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. I show that the theoretical prediction for the cross section is significantly enhanced and is greatly stabilized when the higher-order corrections are included.