Jet quenching in high energy heavy ion collisions by QCD synchrotronlike radiation

Abstract

We consider synchrotronlike radiation in QCD by generalizing Schwinger's treatment of quantum synchrotron radiation in QED to the case of a constant chromomagnetic field. We suggest a novel mechanism for jet quenching in heavy ion collisions, whereby high-${p}_{t}$ partons get depleted through strong (classical) color fields. The latter are encountered in the color glass condensate or in the form of expanding shells of exploding sphalerons. Unlike bremsstrahlung radiation through multiple soft rescattering, synchrotron radiation converts a jet into a wide shower of soft gluons. We estimate the energy loss through this mechanism and suggest that it contributes significantly to the unexpectedly strong jet quenching observed at BNL RHIC.