Mach-like emission from nucleon scattering in proton-nucleus reaction

Physical Review C (Impact Factor: 3.88). 06/2011; 83(6). DOI: 10.1103/PhysRevC.83.064607
Source: arXiv

ABSTRACT The fast-stage nucleon emission of proton-nucleus (pA) reactions from 300A
MeV to 1.8A GeV has been investigated using the quantum molecular-dynamics
model. It is found that the sideward angular spectrum of nucleon emission
presents an interesting Mach-like structure at the early stage of the collision
(tens of fm/c). The sideward angular peak value varies from about 45\circ to
near 73\circ, depending on the bombarding energy. Nucleons emitted from the
vicinity of the sideward peak tend to have a fixed momentum value about 0.5
GeV/c, independent of the bombarding energy as well as the impact parameter.
Additionally, the sideward angular peak value is almost independent of the
equation of state, indicating that binary collision at the early fast stage in
the intermediate energy pA reaction plays an important role in the emergence of
Mach-like emission.

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Available from: Xi-Guang Cao, Aug 26, 2015
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