论文标题
测量暗物质的量子状态
Measuring the Quantum State of Dark Matter
论文作者
论文摘要
我演示了一个简单的示例，说明了如何从搜索超轻质骨化暗物质（DM）（例如轴）中获得的时间序列来确定它是否处于相干还是不连贯的量子状态。这个例子本质上是微不足道的，但我希望明确解决它会引起实验探索。在标准相干状态下，$ \ Mathcal {o}（1）$数量密度的振荡发生在连贯性的时间内，$τ_c= h/m v^2 $，其中$ m $是粒子质量，$ v $是银河病毒速度，导致全球范围$ t的降低，导致了在时代$ t时的限制。另一方面，如果DM不连贯，则不会发生这种强的数量振荡，因为不同流中粒子上的集合平均值可得出有效的相平均值。如果一个实验检测到信号，则可以通过在相干时间内的时间序列分析来确定DM的相干性或不相干性质。这一发现在观察上与DM群众相关，$ 10^{ - 17} \ text {ev} \ Lessim m \ Lessim 10^{ - 11} \ text {ev} $（对应于一年和100秒之间的相干时间），并且可以通过包括Casper，dmradio和dmradio和Aion和Aion和Aion的实验来探索。在微波制度的较高质量下，连贯性也可以测量，但我尚未探索它。
I demonstrate a simple example of how the time series obtained from searches for ultralight bosonic dark matter (DM), such as the axion, can be used to determine whether it is in a coherent or incoherent quantum state. The example is essentially trivial, but I hope that explicitly addressing it provokes experimental exploration. In the standard coherent state, $\mathcal{O}(1)$ oscillations in the number density occur over the coherence time, $τ_c=h/m v^2$, where $m$ is the particle mass and $v$ is the galactic virial velocity, leading to a reduction in the constraining power of experiments operating on timescales $T<τ_c$, due to the unknown global phase. On the other hand if the DM is incoherent then no such strong number oscillations occur, since the ensemble average over particles in different streams gives an effective phase average. If an experiment detects a signal then the coherent or incoherent nature of DM can be determined by time series analysis over the coherence time. This finding is observationally relevant for DM masses, $10^{-17}\text{ eV}\lesssim m\lesssim 10^{-11}\text{ eV}$ (corresponding to coherence times between a year and 100 seconds), and can be explored by experiments including CASPEr, DMRadio, and AION. Coherence may also be measurable at higher masses in the microwave regime, but I have not explored it.
