Nucleosynthesis in Strange Star Mergers

Abstract

The possible existence of deconfined matter in the cores of neutron stars has been studied for over three decades without a firm indication either for or against this proposition. Analysis mostly rely on the comparison of mass-radius curves obtained for different compositions with observational data on the mass of the most massive objects of this kind accurately determined. Nevertheless, there are other possibilities for indirectly studying the internal composition of this class of compact objects, e.g, analyzing cooling behavior, X-ray bursts, supernova’s neutrinos. We present calculations on the expected nucleosynthesis spectra for the strange star-strange star merger scenario as means to test the strange quark matter hypothesis and its realization inside such objects. This would result very different from the typical r-process nucleosynthesis expected in neutron star mergers since the high temperature deconfinement of strange matter would produce large amounts of neutrons and protons and the mass buildup would proceed in a Big-Bang nucleosynthesis like scenario. The neutron to proton ratio would allow to reach the iron peak only, a very different prediction from the standard scenario. The resultant light curve indicate it may be compatible with that of a kilonova depending on the specific details of the ejecta.