Induced Gluon Radiation in a Qcd Medium
نویسنده
چکیده
Soft gluon radiation induced by multiple scattering of a fast quark or gluon propagating through QCD matter is discussed. After revisiting the Landau-Pomeranchuk-Migdal effect in QED we show that large formation times of bremsstrahlung quanta determine the QCD radiation intensity (in analogy to QED) and derive the gluon energy spectrum. Coherent suppression takes place as compared to the Bethe-Heitler situation of independent emissions. As a result the energy loss of fast partons in a QCD medium depends on the incident energy E similarly to QED, −dE/dz ∝ √ E. Permanent address: Petersburg Nuclear Physics Institute, Gatchina, 188350 St. Petersburg, Russia ‡ Laboratoire associé du Centre National de la Recherche Scientifique
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