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arXiv · 1603.00467

The unreasonable weakness of r-process cosmic rays in the neutron-star-merger nucleosynthesis scenario

Koutarou Kyutoku·Kunihito Ioka
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Abstract

We reach the robust conclusion that, by combining the observed cosmic rays of r-process elements with the fact that the velocity of the neutron-star-merger ejecta is much higher than that of the supernova ejecta, either (1) the reverse shock in the neutron-star-merger ejecta is a very inefficient accelerator that converts less than 0.003% of the ejecta kinetic energy to the cosmic-ray energy or (2) the neutron star merger is not the origin of the Galactic r-process elements. We also find that the acceleration efficiency should be less than 0.1% for the reverse shock of the supernova ejecta with the observed cosmic rays lighter than the iron.

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Koutarou Kyutoku, Kunihito Ioka. 2016-03-01. The unreasonable weakness of r-process cosmic rays in the neutron-star-merger nucleosynthesis scenario. https://doi.org/10.3847/0004-637x/827/1/83

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