R-process Nucleosynthesis of Subminimal Neutron Star Explosions

Abstract We show that a minimum-mass neutron star undergoes delayed explosion after mass removal from its surface. We couple the Newtonian hydrodynamics to a nuclear reaction network of ∼4500 isotopes to study the nucleosynthesis and neutrino emission during the explosion. An electron antineutrino burst with a peak luminosity of ∼3 × 10 50 erg s −1 is emitted while the ejecta is heated to ∼10 9 K. A robust r -process nucleosynthesis is realized in the ejecta. Lanthanides and heavy elements near the second and third r -process peaks are synthesized as end products of nucleosynthesis, suggesting that subminimal neutron star explosions could be an important source of solar chemical elements.