Astrophysics of the Melbourne University (Australia) clarified the seizure of particles of the dark matter in the neutron stars. Knowing this value allows the use of neutron stars as a possible detector of dark matter. This is reported in the article published in the magazine Physical Review Letters.
It is known that dark matter (DM) is very poorly interacting with the usual (baryonic) matter, which greatly complicates its search, despite the visible effects that it has a galaxic movement. However, neutron stars are so dense that they can catch the particles of dark matter that pass through them. With a mass, comparable with the mass of the Sun, these space objects have a radius of only up to ten kilometers, and the teaspoon of its substance has a lot of about a billion tons.
Theoretically, DM particles face neutrons in a star, lose energy and turn out to be in the gravitational trap, with the result that with time dark matter accumulates in the star core. It is expected that this will lead to heating of old, cold neutron stars to a level noticeable for future observations. In extreme cases, this may cause a sudden collapse of the neutron star into a black hole.
However, to identify abnormally preheated neutron stars or collapsar, it is necessary to know the exact gripping rate of dark matter. Until now, estimates of the capture speed at the Sun, but neutron stars differ from ordinary stars extremely extreme medium, which strongly affects the dispersion of DM particles. The researchers took into account the structure of neutrons and interaction between them. In other words, physicists moved away from the traditional viewing of neutrons as point particles forming the perfect gas. It turned out that these factors suppress energy transmission in the collision of particles of dark matter with neutrons, significantly reducing the capture rate. This suppression of the capture is enhanced to three orders in very massive neutron stars.