Neutron stars change their structure with accumulation of dark matter. We study how their mass is influenced from the environment. Close to the sun, the dark matter accretion from the neutron star does not have any effect on it. Moving towards the galactic center, the density increase in dark matter results in increased accretion. At distances of some fraction of a parsec, the neutron star acquire enough dark matter to have its structure changed. We show that the neutron star mass decreases going towards the galactic centre, and that dark matter accumulation beyond a critical value collapses the neutron star into a black hole. Calculations cover cases varying the dark matter particle mass, self-interaction strength, and ratio between the pressure of dark matter and ordinary matter. This allow us to constrain the interaction cross section, ${\sigma }_{\mathrm{dm}}$, between nucleons and dark matter particles, as well as the dark matter self-interaction cross section.

中文翻译：

---

中子星和暗物质

中子星随着暗物质的积累而改变其结构。我们研究了它们的质量如何受到环境的影响。靠近太阳，中子星产生的暗物质不会对其产生任何影响。朝着银河系中心移动，暗物质的密度增加导致吸积增加。在几分之一秒的距离内，中子星会吸收足够多的暗物质，从而改变其结构。我们表明，中子星质量朝着银河中心方向减少，暗物质积累超过临界值，将中子星坍塌成黑洞。计算涵盖了改变暗物质颗粒质量，自相互作用强度以及暗物质与普通物质之间的压力比的情况。这使我们可以约束交互作用的横截面，${\sigma }_{\mathrm{dm}}$，在核子和暗物质粒子之间，以及暗物质自相互作用截面。