Direct Photons in Heavy-Ion Collisions
نویسنده
چکیده
A brief overview of direct-photon measurements in ultra-relativistic nucleus-nucleus collisions is given. The results for Pb+Pb collisions at √ sNN = 17.3 GeV and for Au+Au collisions at √ sNN = 200 GeV are compared to estimates of the direct-photon yield from hard scattering. Both results leave room for a significant thermal photon component. A description purely based on hard scattering processes, however, is not ruled out so far.
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تاریخ انتشار 2006