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Neutron stars hide a special type of matter inside: an exotic quark mixture

Neutron stars hide a special type of matter inside

Neutron stars are mysterious objects that are of interest to modern science. The astrophysicists pay close attention to the study of massive neutron stars. Their attention was rewarded. The research team has strong evidence that the nuclei of the largest neutron stars contain an exotic “mixture” of subatomic particles called quarks. The scientists carried new calculations using data from gravitational waves discovered for the first time after a collision of neutron stars in the summer of 2017.

And they showed that the nuclei of neutron stars are so dense that atoms cease to exist in them. They are turning into a unique new quark matter. That discovery was made by a group of theoretical physicists at the University of Helsinki.


According to researcher Alexi Vuorinen, special matter may exist inside the nuclei of neutron stars. But for 40 years it has been impossible to prove that, and now the science has an evidence. Neutron stars are considered as dead. These are the destroyed remains of giant stars, their masses were from 8 to 30 solar masses.

When these stars become supernovae, most of their mass is thrown into space. The core remains, which forms into a very dense object. In the process of conversion into a supernova, the protons and electrons that are in atoms become neutrons and neutrinos. Neutrinos remain under high pressure.

It forces the elements to merge together, which leads to the creation of a neutron star with one huge and very dense core. At a sufficiently high temperature and density inside the nucleus, neutrons begin the decay period. They become quarks, forming a kind of mixture inside the nucleus.


And although it is actually difficult to understand what is inside the nucleus of a neutron star, the scientists, observing in 2017 the change in two such stars, have witnessed the gravitational deformation of both space objects. That helped the researchers to calculate the features of the internal structure of the nuclei of neutron stars and obtain evidence of the existence of a special type of matter.