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arXiv · 1203.3175

Particle yields in heavy ion collisions and the influence of strong magnetic fields

M. G. de Paoli·D. P. Menezes
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Abstract

It is expected that the magnetic field in the surface of magnetars do not exceed $10^{15}$ G. However, in heavy ion collisions, this value is expected to be much higher. We investigate the effects of a magnetic fields varying from $10^{18}$, to $10^{20}$ G in strange matter (composed of $u$, $d$ and $s$ quarks). We model matter as a free gas of baryons and mesons under the influence of an external magnetic field. We study the effects of such strong fields through a $\chi^2$ fit to some data sets of the STAR experiment. For this purpose we solve the Dirac, Rarita-Schwinger, Klein-Gordon and Proca equations subject to magnetic fields in order to obtain the energy expressions and the degeneracy for spin 1/2, spin 3/2, spin 0 and spin 1 particles, respectively. Our results show that a field of the order of $10^{19}$ G produces an improved fitting to the experimental data as compared to the calculations without magnetic field.

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M. G. de Paoli, D. P. Menezes. 2012-03-14. Particle yields in heavy ion collisions and the influence of strong magnetic fields. https://doi.org/10.1063/1.4804121

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