Department of Physics, University of Notre Dame, 225 Nieuwland Science Hall, Notre Dame, Indiana 46556, USA.
Kavli Institute for Cosmological Physics, University of Chicago, 5640 South Ellis Avenue, Chicago, Illinois 60637, USA.
Phys Rev Lett. 2014 Nov 7;113(19):191301. doi: 10.1103/PhysRevLett.113.191301. Epub 2014 Nov 3.
The paucity of old millisecond pulsars observed at the galactic center of the Milky Way could be the result of dark matter accumulating in and destroying neutron stars. In regions of high dark matter density, dark matter clumped in a pulsar can exceed the Schwarzschild limit and collapse into a natal black hole which destroys the pulsar. We examine what dark matter models are consistent with this hypothesis and find regions of parameter space where dark matter accumulation can significantly degrade the neutron star population within the galactic center while remaining consistent with observations of old millisecond pulsars in globular clusters and near the solar position. We identify what dark matter couplings and masses might cause a young pulsar at the galactic center to unexpectedly extinguish. Finally, we find that pulsar collapse age scales inversely with the dark matter density and linearly with the dark matter velocity dispersion. This implies that maximum pulsar age is spatially dependent on position within the dark matter halo of the Milky Way. In turn, this pulsar age spatial dependence will be dark matter model dependent.
在银河系中心观测到的古老毫秒脉冲星数量稀少,可能是暗物质在其中积累并破坏中子星的结果。在暗物质密度较高的区域,脉冲星内聚集的暗物质可能会超过史瓦西极限,并塌缩成一个原初黑洞,从而破坏脉冲星。我们研究了哪些暗物质模型与这一假设一致,并找到了暗物质积累可以显著降低银河系中心内中子星数量的参数空间区域,同时与球状星团和太阳附近观测到的古老毫秒脉冲星保持一致。我们确定了哪些暗物质耦合和质量可能导致银河系中心的年轻脉冲星意外熄灭。最后,我们发现脉冲星的坍缩年龄与暗物质密度成反比,与暗物质速度分散度成正比。这意味着最大的脉冲星年龄在空间上取决于银河系暗物质晕的位置。反过来,这种脉冲星年龄的空间依赖性将取决于暗物质模型。