, in other cases there is no explosion. Instead, the star's core collapses under gravity so severely it forms a black hole that eventually causes the rest of the star to cave in around it.
"What our study shows is that there is always a gap in black-hole masses between 9 and 16 solar masses,” Schneider told Space.com.The existence of the mass gap is dictated by what is happening inside a massive star as it nears the end of its life. processes; in massive stars, the dominant version of this process is known as the carbon–nitrogen–oxygen cycle.
An illustration of gravitational waves being emitted by binary black holes spiraling towards a merger In a binary system, this can lead to two black holes that eventually merge with a chirp of gravitational waves.