Related papers: The LPM effect in sequential bremsstrahlung: analy…
Considering $2\to 2$ gauge-theory scattering with general colour in the high-energy limit, we compute the Regge-cut contribution to three loops through next-to-next-to-leading high-energy logarithms (NNLL) in the signature-odd sector. Our…
Using the improved value of the screening angular parameter in the quasiclassical approximation of the Moliere multiple scattering theory we show that the best agreement between the Migdal theory of the LPM-effect and experiment is achieved…
The induced momentum spectrum of soft gluons radiated from a high energy quark produced in and propagating through a QCD medium is reexamined in the BDMPS formalism. A mistake in our published work (Physical Review C60 (1999) 064902) is…
We study the effects of gluon interference in the production and semi-leptonic decay of a t-tbar pair above threshold at the Next Linear Collider (NLC). We calculate all matrix elements to next-to-leading order and use the resulting…
When an energetic parton propagates in a hot and dense QCD medium it loses energy by elastic scatterings or by medium-induced gluon radiation. The gluon radiation spectrum is suppressed at high frequency due to the LPM effect and…
High-energy partons ($E \gg T$) traveling through a quark-gluon plasma lose energy by splitting via bremsstrahlung and pair production. Regardless of whether or not the quark-gluon plasma itself is strongly coupled, an important question…
It is proposed to identify a strong electric field - created during relativistic collisions of asymmetric nuclei - via the observation of pseudorapidity and transverse momentum distributions of hadrons with the same mass but opposite…
It is argued that heavy-quarks traversing a Quark Gluon Plasma, undergo a multi-stage modification process, similar to the case of light flavors. Such an approach is applied to heavy-quark energy loss, which includes a rare-scattering,…
The short-distance behaviour of the hadronic light-by-light (HLbL) contribution to $(g-2)_{\mu}$ has recently been studied by means of an operator product expansion in a background electromagnetic field. The leading term in this expansion…
With the aim to extend the study of inclusive heavy quarkonium production at forward rapidities with the resummation of high partonic center-of-momentum-energy logarithms beyond Leading Logarithmic Approximation (LLA), the explicit analytic…
We present quantitative results on the cross section for $\gamma + \gamma (J_z=0) \to b \bar{b}\to two b$-jets based on the recently achieved all orders resummation of large soft (Sudakov) and hard (non-Sudakov) double logarithms. The…
I report on some theoretical progress concerning the calculation of gluon bremsstrahlung for very high energy particles crossing a weakly-coupled quark-gluon plasma. (i) I advertise that two of the several formalisms used to study this…
We consider three-loop radiative-recoil corrections to hyperfine splitting in muonium generated by the gauge invariant set of diagrams with virtual light-by-light scattering block. These corrections are enhanced by the large logarithms of…
The measurements of the $\gamma\gamma$ and $b \bar b$ partial decay widths of an intermediate-mass Standard Model Higgs boson are among the most important goals of a future photon linear collider. While in an initially polarized $J_z=0$…
A formalism is presented in which the radiation of photons off high energy electrons during a multiple scattering process with finite condensed media can be evaluated for a general interaction. We show that the arising…
We gauge the impact of soft-gluon resummation on quark distributions by performing a simple fit of Deep Inelastic Scattering structure function data using next-to-leading order (NLO) and next-to-leading-logarithmic (NLL)-resummed…
We review the perturbative approach to multiparticle production in hard collision processes. It is investigated to what extent parton level analytical calculations at low momentum cut-off can reproduce experimental data on the hadronic…
In contrast to the damping of partons in a quark-gluon plasma, the damping of a scalar particle in a hot scalar QED plasma can be calculated to leading order for the whole momentum range using the Braaten-Pisarski method. In this way the…
Linear and non-linear QCD evolutions at high energy suffer from severe issues related to convergence, due to higher order corrections enhanced by large double and single transverse logarithms. We resum double logarithms to all orders by…
We study the leading logarithmic QCD corrections to Higgs pair production in the high-energy limit, which originate from soft quark exchange in the Feynman diagram and are thus suppressed by the quark mass. It is found that triangle Feynman…