In 2017, a cosmic element birth came to light when two dead neutron-rich stars collided and spewed out gold, platinum and other massive elements (SN: 16/10/17). (Read also; Scientists Find Evidence of Planets Outside the Milky Way )
A few years later, when another neutron star collided with a black hole. This event made scientists wonder which type of cosmic collision was more productive for the formation of a large element (SN: 29/6/21).
Now, they have an answer. Scientists in the Astrophysical Journal Letters on October 25, 2021 wrote a surprising report regarding the collision of two neutron stars. In order to form heavy elements after the collision, neutron star material must be ejected into space.
Then through a series of nuclear reactions called the r-process can convert these materials into heavy elements (SN: 22/4/16). The r-process is a nucleosynthesis process, which occurs in a supernova that undergoes a nuclear collapse to form almost half of the atomic nucleus that is rich in neutrons, namely heavy metals.
How much material escapes into space, if any, depends on a variety of factors. For example, in the collision of a neutron star and a black hole, the black hole must be relatively small. “Or no hope at all. It will immediately engulf the neutron star, without ejecting anything,” said astrophysicist Hsin-Yu Chen of MIT.
Chen and his fellow scientists considered various possibilities for neutron star and black hole collisions, such as the distribution of mass and how fast they spin. The team then calculated the mass ejected by each type of collision under these varying conditions. (Also read; The First Planet Outside the Milky Way Galaxy With The Size Of Saturn Found)
In most scenarios, the neutron star-black hole merger produces a smaller amount of heavy elements than the neutron star duo. In one case only about one hundredth of the amount.