科学家发现银河系光晕中没有大质量黑洞
近日，波兰华沙大学的Przemek Mroz及其研究团队取得一项新进展。经过不懈努力，他们发现银河系光晕中没有大质量黑洞。相关研究成果已于2024年6月24日在国际权威学术期刊《自然》上发表。
该研究团队在长达20年的OGLE调查中，对大麦哲伦星云内近8000万颗恒星的光曲线进行了深入分析，以寻找长时间微透镜事件。研究人员没有发现任何时间尺度超过一年的事件，而所有检测到的较短期事件均可用已知的恒星群体来合理解释。研究发现，质量在1.8×10-4至6.3M⊙之间的致密天体组成的暗物质占比不会超过1%，而对于质量在1.3×10-5至860M⊙之间的致密天体，其组成的暗物质占比也不会超过10%。这意味着，在这个质量范围内的原生黑洞无法同时解释暗物质的主要部分和观测到的引力波事件。
据悉，引力波探测器揭示了一群巨大的黑洞，它们与在银河系中观察到的黑洞不同，它们的起源也存在争议。根据一种可能的解释，这些黑洞可能是由早期宇宙(原始黑洞)的密度波动形成的，它们应该由几种到100%的暗物质组成，以解释观察到的黑洞合并率。如果这样的黑洞存在于银河系的暗物质晕中，它们将导致持续数年的长时间引力微透镜事件。以前的实验对这类事件不够敏感。
附：英文原文
Title: No massive black holes in the Milky Way halo
Author: Mroz, Przemek, Udalski, Andrzej, Szymaski, Micha K., Soszyski, Igor, Wyrzykowski, ukasz, Pietrukowicz, Pawe, Kozowski, Szymon, Poleski, Radosaw, Skowron, Jan, Skowron, Dorota, Ulaczyk, Krzysztof, Gromadzki, Mariusz, Rybicki, Krzysztof, Iwanek, Patryk, Wrona, Marcin, Ratajczak, Milena
Issue&Volume: 2024-06-24
Abstract: The gravitational wave detectors have unveiled a population of massive black holes that do not resemble those observed in the Milky Way and whose origin is debated. According to one possible explanation, these black holes may have formed from density fluctuations in the early Universe (primordial black holes), and they should comprise from several to 100% of dark matter to explain the observed black hole merger rates. If such black holes existed in the Milky Way dark matter halo, they would cause long-timescale gravitational microlensing events lasting years. The previous experiments were not sufficiently sensitive to such events. Here we present the results of the search for long-timescale microlensing events among the light curves of nearly 80 million stars located in the Large Magellanic Cloud that were monitored for 20 years by the OGLE survey. We did not find any events with timescales longer than one year, whereas all shorter events detected may be explained by known stellar populations. We find that compact objects in the mass range from 1.8×10-4 to 6.3M⊙ cannot compose more than 1% of dark matter, and those in the mass range from 1.3×10-5 to 860M⊙ cannot make up more than 10% of dark matter. Thus, primordial black holes in this mass range cannot simultaneously explain a significant fraction of dark matter and gravitational wave events.
DOI: 10.1038/s41586-024-07704-6
Source: https://www.nature.com/articles/s41586-024-07704-6
来源：科学网 小柯机器人
