Space-time structure of initial parton production in ultrarelativistic heavy ion collisions.
نویسندگان
چکیده
The space and time evolution of initial parton production in ultrarelativistic heavy ion collisions is investigated within the framework of perturbative QCD which includes both initial and final state radiations. Uncertainty principle is used to relate the life time of a radiating parton to its virtuality and momentum. The interaction time of each hard or semihard parton scattering is also taken into account. For central Au + Au collisions at √ s=200 GeV, most of the partons are found to be produced within 0.5 fm/c after the total overlap of the two colliding nuclei. The local momentum distribution is approximately isotropical at that time. The implication on how to treat correctly the the secondary scattering in an ultimate parton cascading model is also discussed.
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عنوان ژورنال:
- Physical review. D, Particles and fields
دوره 49 3 شماره
صفحات -
تاریخ انتشار 1994