Oppenheimer-Volkoff limit

The Tolman-Oppenheimer-Volkoff (TOV) limit is an upper bound to the mass of stars composed of neutron-degenerate matter (neutron stars). It is analogous to the Chandrasekhar limit for white dwarf stars.The limit was computed by Julius Robert Oppenheimer and George Michael Volkoff in 1939, using work of Richard Chace Tolman. Oppenheimer and Volkoff assumed that the neutrons in a neutron star formed a cold, degenerate Fermi gas. This leads to a limiting mass of approximately 0.7 solar masses., Modern estimates range from approximately 1.5 to 3.0 solar masses. The uncertainty in the value reflects the fact that the equations of state for extremely dense matter are not well-known.
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. The mass limit at which baryon degeneracy pressure is no longer sufficient to resist gravity . This occurs for inert masses of between three and five solar masses. It is the upper limit for the mass of a neutron star and the lower limit for the mass of a black hole .