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arXiv · 1208.5428

Disentangling effects of collision geometry and symmetry energy in U+U collisions

Jun Xu·Zachary Martinot·Bao-An Li
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Abstract

Effects of the collision geometry on experimental observables that are known to be sensitive to the high-density behavior of nuclear symmetry energy are examined in U+U collisions at 0.52 GeV/nucleon using an isospin- and momentum-dependent interaction within the framework of IBUU transport model. It is found that the neutron-proton differential flow in tip-tip collisions and the difference of neutron and proton elliptic flow in body-body collisions are more sensitive to the symmetry energy at supra-saturation densities compared with collisions of spherical nuclei of the same masses. In addition, the n/p ratio of pre-equilibrium nucleons is found to be slightly more sensitive to the symmetry energy in tip-tip collisions, and the collision geometry affects the \pi^-/\pi^+ ratio significantly.

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Jun Xu, Zachary Martinot, Bao-An Li. 2012-08-27. Disentangling effects of collision geometry and symmetry energy in U+U collisions. https://doi.org/10.1103/physrevc.86.044623

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