Related papers: Soft-Gluon Angular Screening in Heavy-Quark Fragme…
The probability distribution D(epsilon) in the energy loss incurred by incoming and outgoing hard quarks in a QCD medium is computed numerically from the BDMPS gluon spectrum. It is shown to follow an empirical log-normal behavior which…
We present a detailed analysis of the use of heavy quark fragmentation into heavy hadrons for testing the heavy quark effective theory through comparison of the measured fragmentation parameters of the $c$ and $b$ quarks. Our analysis is…
The gluon radiation induced by multiple scattering of a hard parton in expanding quark-gluon plasma is investigated. The radiative energy loss of hard parton jet is shown to decrease considerably when angular size of extracted jet goes up,…
The case of gluon bremsstrahlung off a heavy quark in extended nuclear matter is revisited within the higher twist formalism. In particular, the in-medium modification of "semi-hard" heavy quarks is studied, where the momentum of the heavy…
In heavy-ion collisions at the LHC a hot and dense medium of deconfided partons, the Quark-Gluon Plasma (QGP), is created. Its global properties can be characterized by the measurements of particles in the low transverse momentum (or…
Utilizing the generalized factorization of twist-4 processes, we derive the modified heavy quark fragmentation function after considering the gluon radiation induced by multiple scattering in DIS. It is found that the mass effects of heavy…
The energy loss of heavy quarks in a quark-gluon plasma of finite size is studied within the light-cone integral approach. A simple analytical formulation of the radiative energy loss of heavy quarks is derived. This provides a convenient…
We calculate diffusion and hadronization of heavy quarks in high-energy heavy-ion collisions implementing the notion of a strongly coupled quark-gluon plasma in both micro- and macroscopic components. The diffusion process is simulated…
Diffractive hard scattering is interpreted as the effect of soft gluon exchanges between the emerging energetic quarks and the nucleon's color field, resulting in an overall color singlet exchange. Summing multiple gluon exchanges to all…
The cross section for bottom quark production is calculated for the HERA-B experiment. We consider both the order $\alpha_s^3$ cross section and the resummation of soft gluon corrections in all orders of QCD perturbation theory.
A program to simulate the production of heavy quarks through the boson-gluon fusion process in $e^{\pm}p$ collisions is presented. The full electro\-weak structure of the electron--gluon interaction is taken into account as well as the…
I review recent results on soft gluon radiation at large angles
The multiplicity of heavy quarks from gluon splitting in e+e- annihilation has now been theoretically calculated and experimentally measured at LEP. However, the experimental measurement requires theoretical input for the shape of the…
An effective field theory framework is developed to study the interaction of heavy quarks in strongly coupled quark-gluon plasma (QGP). The latter is treated as a relativistic non-dissipative colorless fluid which can be studied using a…
The process e+e- ---> q(bar) q g g where all final particles are hard is treated in a semi-analytic approach. Cuts on the invariant masses of the quark and the gluon pair can be applied. The total cross section is obtained by three…
We investigate the effect of a non-perturbative gluon condensate on the spectrum of bound states of extremely heavy quarks using Non-Relativistic-QCD (NRQCD). Simulations are done with an improved gluon action on small lattices. We compare…
A hot, dense medium called a Quark Gluon Plasma (QGP) is created in ultrarelativistic heavy ion collisions. Hard parton scatterings generate high momentum partons that traverse the medium, which then fragment into sprays of particle called…
In this paper, we show that multiple maximally soft (anti-)quark and gluon emissions exponentiate at the level of either the amplitude or cross-section. We first show that such emissions can be captured by introducing new soft emission…
This lecture presents a concise review of the current status of hard QCD and electromagnetic processes as probes of the quark-gluon plasma.
The first measurements of the diffractive structure function $F_2^{D(3)}$ at HERA are discussed. A factorisable interpretation in which a partonic structure is assigned to the pomeron is investigated through QCD analyses in which both the…