1999ApJ...517L.117R

GRB 990123 may have produced 4x10⁵⁴ ergs in gamma rays unless, as seems to be the case, it was significantly beamed. Even with beaming, it may be beyond the limiting binding energy available for neutron star mergers in the Schwarzschild metric. Neutron stars of ∼10 M_☉ are permitted in the Yilmaz metric. A merger of two neutron stars of about 10 M_☉ could release approximately 3x10⁵⁵ ergs. The spectral state switches of the galactic black hole candidates may be the signatures of the magnetic fields of such massive neutron stars.