Let us assume that two neutron stars with masses 
and 
are merging. The following state of the after-merging object
is determined by the ratio
of the resulting total mass and the Oppenheimer-Volkoff limit.
Two different scenarios may be distinguished as follows
(Lipunova & Lipunov, 1998):
Here and below we interpret the Oppenheimer-Volkoff limit not as the
standard value derived for the cold equation of state of baryonic matter
for a non-rotating neutron star, but as a modified one.
In the general case the Oppenheimer-Volkoff limit is a function of
the angular spin velocity of the object, its entropy, and the specific
equation of state: 
.
Each neutron star can have a mass lying between the limits:
-- derived by Landau (1938).
-- commonly suggested now.