Anomalous mass dependence of radiative quark energy loss in a finite-size quark-gluon plasma

We demonstrate that for a finite-size quark-gluon plasma the induced gluon radiation from heavy quarks is stronger than that for light quarks when the gluon formation length becomes comparable with (or exceeds) the size of the plasma. The effect is due to oscillations of the light-cone wave function for the in-medium $q\to gq$ transition. The dead cone model by Dokshitzer and Kharzeev neglecting quantum finite-size effects is not valid in this regime. The finite-size effects also enhance the photon emission from heavy quarks.Comment: 8 pages, 3 figure

Transverse Spectra of Radiation Processes in Medium

We develop a formalism for evaluation of the transverse momentum dependence of cross sections of the radiation processes in medium. The analysis is based on the light-cone path integral approach to the induced radiation. The results are applicable in both QED and QCD

Radiative parton energy loss and jet quenching in high-energy heavy-ion collisions

We study within the light-cone path integral approach [3] the effect of the induced gluon radiation on high-p_{T} hadrons in high-energy heavy-ion collisions. The induced gluon spectrum is represented in a new form which is convenient for numerical simulations. For the first time, computations are performed with a realistic parametrization of the dipole cross section. The results are in reasonable agreement with suppression of high-p_{T} hadrons in Au+Au collisions at \sqrt{s}=200 GeV observed at RHIC.Comment: 12 pages, 3 epsi figures. Typos correcte

Collinear Photon Emission from the Quark-Gluon Plasma: The Light-Cone Path Integral Formulation

We give a simple physical derivation of the photon emission rate from the weakly coupled quark-gluon plasma connected with the collinear processes $q\to \gamma q$ and $q\bar{q}\to \gamma$. The analysis is based on the light-cone path integral approach to the induced radiation. Our results agree with that by Arnold, Moore and Yaffe obtained using the real-time thermal perturbation theory. It is demonstrated that the solution of the AMY integral equation is nothing but the time-integrated Green's function of the light-cone path integral approach written in the momentum representation.Comment: 12 pages, 2 figure

Direct calculation of the triple-pomeron coupling for diffractive DIS and real photoproduction

We present a unified direct calculation of the triple-pomeron coupling A_{3\Pom}(Q^{2}) for diffractive real photoproduction ($Q^{2}=0$) and deep inelastic scattering at large $Q^{2}$ in the framework of the dipole approach to the generalized BFKL pomeron. The small phenomenological value of A_{3\Pom}(0)\approx 0.16\,GeV$^{2}$, which was a mystery, is related to the small correlation radius $R_{c}\approx 0.3$\,fm for the perturbative gluons. We confirm the early expectations of weak $Q^{2}$ dependence of the dimensionfull coupling A_{3\Pom}(Q^{2}) and predict that it rises by the factor $\sim 1.6$ from real photoproduction to deep inelastic scattering.Comment: 14 pages, 1 figure (request from [email protected]), Juelich preprint KFA-IKP(Th)-1994-3