论文标题
通过Superfluid 4HE中的声子创建搜索低质量暗物质
Searching for low mass dark matter via phonon creation in superfluid 4He
论文作者
论文摘要
我们认为从超流体液体$^4 $ He中散射暗物质颗粒，这已被提议作为其直接检测的目标。在〜1 meV以下的暗物质质量上，我们从总结参数中证明了具有Energies $ω\ Lessim 1 $ MEV的单声子生产的重要性。 We show further that the anomalous dispersion of phonons in liquid $^4$He at low pressures [i.e., $d^2ω(q)/dq^2>0$, where $q$ and $ω(q)$ are the phonon momentum and energy] has the important consequence that a single phonon will decay over a relatively short distance into a shower of lower energy phonons centered on the direction of the original phonon.因此，该制度的实验挑战是检测一个低能声子的淋浴，而不仅仅是一个声子。在这种淋浴中声子分布中的其他信息可以增强暗物质质量的测定。
We consider the scattering of dark matter particles from superfluid liquid $^4$He, which has been proposed as a target for their direct detection. Focusing on dark matter masses below ~1 MeV, we demonstrate from sum-rule arguments the importance of the production of single phonons with energies $ω\lesssim 1$ meV. We show further that the anomalous dispersion of phonons in liquid $^4$He at low pressures [i.e., $d^2ω(q)/dq^2>0$, where $q$ and $ω(q)$ are the phonon momentum and energy] has the important consequence that a single phonon will decay over a relatively short distance into a shower of lower energy phonons centered on the direction of the original phonon. Thus the experimental challenge in this regime is to detect a shower of low energy phonons, not just a single phonon. Additional information from the distribution of phonons in such a shower could enhance the determination of the dark matter mass.
