An Isolated Mass-gap Black Hole or Neutron Star Detected with Astrometric Microlensing-猫眼课题宝

DOI：

10.3847/2041-8213/ac7442

发表时间：

2022-02

期刊：

The Astrophysical Journal Letters

影响因子：

通讯作者：

中科院分区：

其他

文献类型：

作者：

C. Lam;Jessica R. Lu;A. Udalski;I. Bond;D. Bennett;J. Skowron;P. Mróz;R. Poleski;T. Sumi;M. Szymański;S. Kozłowski;P. Pietrukowicz;I. Soszyński;K. Ulaczyk;Ł. Wyrzykowski;S. Miyazaki;D. Suzuki;N. Koshimoto;N. Rattenbury;M. Hosek;F. Abe;R. Barry;A. Bhattacharya;A. Fukui;H. Fujii;Y. Hirao;Y. Itow;R. Kirikawa;I. Kondo;Y. Matsubara;Sho Matsumoto;Y. Muraki;G. Olmschenk;C. Ranc;A. Okamura;Y. Satoh;S. I. Silva;T. Toda;P. Tristram;A. Vandorou;H. Yama;N. Abrams;S. Agarwal;S. Rose;S. Terry

我们提出了五个黑洞候选人的引力微透镜调查确定的分析。哈勃空间望远镜的天体测量数据和地面微透镜测量的密集采样光变曲线与单源、单透镜微透镜模型相匹配，以测量每个透镜的质量和光度，并确定它是否是黑洞。五个目标中的一个（OGLE-2011-BLG-0462/MOA-2011-BLG-191或简称OB 110462）显示出明显的>1质量的相干天体测量偏移，几乎没有透镜通量，并推断出透镜质量为1.6-4.4 M质量。这使得OB 110462成为第一个通过天体测量微透镜发现的紧凑物体，它很可能是中子星星或低质量黑洞。这个紧凑的物体透镜相对较近（0.70-1.92 kpc），并且具有<30 km s-1的缓慢横向运动。OB 110462显示出测光模型与天体测量模型之间的巨大张力，使得目前很难区分中子星星和黑洞。需要额外的观测和更复杂的系统几何形状的建模，如二进制源，以解决这个对象的令人困惑的性质。剩下的四个候选者的透镜质量都小于2 M，它们不太可能是黑洞;其中两个可能是白色矮星或中子星。我们将五个候选者的完整样本与银河系中黑洞数量的理论预期（1008）进行比较，并在小样本的情况下找到合理的一致性。

We present the analysis of five black hole candidates identified from gravitational microlensing surveys. Hubble Space Telescope astrometric data and densely sampled light curves from ground-based microlensing surveys are fit with a single-source, single-lens microlensing model in order to measure the mass and luminosity of each lens and determine if it is a black hole. One of the five targets (OGLE-2011-BLG-0462/MOA-2011-BLG-191 or OB110462 for short) shows a significant >1 mas coherent astrometric shift, little to no lens flux, and has an inferred lens mass of 1.6–4.4 M ⊙. This makes OB110462 the first definitive discovery of a compact object through astrometric microlensing and it is most likely either a neutron star or a low-mass black hole. This compact-object lens is relatively nearby (0.70–1.92 kpc) and has a slow transverse motion of <30 km s−1. OB110462 shows significant tension between models well fit to photometry versus astrometry, making it currently difficult to distinguish between a neutron star and a black hole. Additional observations and modeling with more complex system geometries, such as binary sources, are needed to resolve the puzzling nature of this object. For the remaining four candidates, the lens masses are <2M ⊙, and they are unlikely to be black holes; two of the four are likely white dwarfs or neutron stars. We compare the full sample of five candidates to theoretical expectations on the number of black holes in the Milky Way (∼108) and find reasonable agreement given the small sample size.

An Isolated Mass-gap Black Hole or Neutron Star Detected with Astrometric Microlensing

文献摘要

相似文献