Nitz Alexander H, Wang Yi-Fan
Max-Planck-Institut für Gravitationsphysik (Albert-Einstein-Institut), D-30167 Hannover, Germany and Leibniz Universität Hannover, D-30167 Hannover, Germany.
Phys Rev Lett. 2021 Jan 15;126(2):021103. doi: 10.1103/PhysRevLett.126.021103.
We present the first search for gravitational waves from the coalescence of stellar mass and subsolar mass black holes with masses between 20-100 M_{⊙} and 0.01-1 M_{⊙}(10-10^{3} M_{J}), respectively. The observation of a single subsolar mass black hole would establish the existence of primordial black holes and a possible component of dark matter. We search the ∼164 day of public LIGO data from 2015-2017 when LIGO-Hanford and LIGO-Livingston were simultaneously observing. We find no significant candidate gravitational-wave signals. Using this nondetection, we place a 90% upper limit on the rate of 30-0.01 M_{⊙} and 30-0.1 M_{⊙} mergers at <1.2×10^{6} and <1.6×10^{4} Gpc^{-3} yr^{-1}, respectively. If we consider binary formation through direct gravitational-wave braking, this kind of merger would be exceedingly rare if only the lighter black hole were primordial in origin (<10^{-4} Gpc^{-3} yr^{-1}). If both black holes are primordial in origin, we constrain the contribution of 1(0.1)M_{⊙} black holes to dark matter to <0.3(3)%.
我们首次对恒星质量黑洞与次太阳质量黑洞合并产生的引力波进行了搜索，这些黑洞的质量分别在20 - 100M⊙和0.01 - 1M⊙（10 - 10³MJ）之间。观测到单个次太阳质量黑洞将证实原初黑洞的存在以及暗物质的一种可能成分。我们搜索了2015 - 2017年LIGO汉福德和LIGO利文斯顿同时进行观测期间约164天的公开LIGO数据。我们未发现显著的候选引力波信号。利用这一未探测结果，我们分别对质量为30 - 0.01M⊙和30 - 0.1M⊙的黑洞合并率设定了90%的上限，分别为<1.2×10⁶和<1.6×10⁴Gpc⁻³yr⁻¹。如果我们考虑通过直接引力波制动形成双星，那么如果只有较轻的黑洞是原初起源的，这种合并将极其罕见（<10⁻⁴Gpc⁻³yr⁻¹）。如果两个黑洞都是原初起源的，我们将1（0.1）M⊙黑洞对暗物质的贡献限制在<0.3（3）%。
