136 citations · 1.2k across the 27 of their papers we have counts for
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Order alpha^7 ln(1/alpha) Contribution to Positronium Hyperfine Splitting
Bernd A. Kniehl, Alexander A. Penin
The logarithmically enhanced alpha^7 ln(1/alpha) contribution to the hyperfine splitting of the positronium ground-state energy levels is calculated in the framework of dimensional…
Top quark threshold production in collisions: current theoretical issues
A. A. Penin
The top quark-antiquark pair threshold production at future High Energy Photon Colliders is considered in view of the recent advances in the theoretical description of the nonrelat…
Heavy Quarkonium Physics beyond the Next-to-Next-to-Leading Order of NRQCD
A. A. Penin
In this talk I briefly review the recent progress in calculation of the high order corrections to the parameters of the nonrelativistic heavy quark-antiquark system in the effectiv…
Subleading Sudakov Logarithms in Electroweak Processes
J. H. Kühn, A. A. Penin, V. A. Smirnov
Recent results for the asymptotic behavior of fermion scattering amplitudes in the Sudakov limit are presented including next-to-leading logarithmic corrections. These are used for…
Order alpha^3 ln(1/alpha) Corrections to Positronium Decays
Bernd A. Kniehl, Alexander A. Penin
The logarithmically enhanced alpha^3 ln(1/alpha) corrections to the para- and orthopositronium decay widths are calculated in the framework of dimensionally regularized nonrelativi…