We present a first exploration of the results of neutron star-black hole mergers using black hole masses in the most likely range of 7 M _ { \odot } \textrm { - - } 10 M _ { \odot } , a neutrino leakage scheme , and a modeling of the neutron star material through a finite-temperature nuclear-theory based equation of state .
In the range of black hole spins in which the neutron star is tidally disrupted ( \chi _ { BH } \gtrsim 0.7 ) , we show that the merger consistently produces large amounts of cool ( T \lesssim 1 { MeV } ) , unbound , neutron-rich material ( M _ { ej } \sim 0.05 M _ { \odot } \textrm { - - } 0.20 M _ { \odot } ) .
A comparable amount of bound matter is initially divided between a hot disk ( T _ { max } \sim 15 { MeV } ) with typical neutrino luminosity L _ { \nu } \sim 10 ^ { 53 } { erg / s } , and a cooler tidal tail .
After a short period of rapid protonization of the disk lasting \sim 10 { ms } , the accretion disk cools down under the combined effects of the fall-back of cool material from the tail , continued accretion of the hottest material onto the black hole , and neutrino emission .
As the temperature decreases , the disk progressively becomes more neutron-rich , with dimmer neutrino emission .
This cooling process should stop once the viscous heating in the disk ( not included in our simulations ) balances the cooling .
These mergers of neutron star-black hole binaries with black hole masses M _ { BH } \sim 7 M _ { \odot } \textrm { - - } 10 M _ { \odot } and black hole spins high enough for the neutron star to disrupt provide promising candidates for the production of short gamma-ray bursts , of bright infrared post-merger signals due to the radioactive decay of unbound material , and of large amounts of r-process nuclei .