该研究团队使用卡鲁阵列望远镜(MeerKAT)对位于球状星团NGC 1851中的偏心双毫秒脉冲星PSR J05144002E进行了精确的脉冲星计时观测。研究人员发现双星的总质量为3.887±0.004倍太阳质量(M⊙),多波长观测表明,这颗脉冲星的双星伴星也是一个致密的天体。
伴星的质量(2.09到2.71M⊙,95%置信区间)处于质量间隙,表明要么是一个非常大质量的黑洞,要么是一个低质量的黑洞。研究人员认为伴星是由两个早期的超新星合并形成的。
据悉,在引力波事件中观测到的一些致密天体的质量位于已知的中子星(NSs)和黑洞(BHs)之间。这些质量间隙天体的性质是未知的,它们的宿主双星系统的形成机制也是未知的。
附:英文原文
Title: A pulsar in a binary with a compact object in the mass gap between neutron stars and black holes
Author: Ewan D. Barr, Arunima Dutta, Paulo C. C. Freire, Mario Cadelano, Tasha Gautam, Michael Kramer, Cristina Pallanca, Scott M. Ransom, Alessandro Ridolfi, Benjamin W. Stappers, Thomas M. Tauris, Vivek Venkatraman Krishnan, Norbert Wex, Matthew Bailes, Jan Behrend, Sarah Buchner, Marta Burgay, Weiwei Chen, David J. Champion, C.-H. Rosie Chen, Alessandro Corongiu, Marisa Geyer, Y. P. Men, Prajwal Voraganti Padmanabh, Andrea Possenti
Issue&Volume: 2024-01-19
Abstract: Some compact objects observed in gravitational wave events have masses in the gap between known neutron stars (NSs) and black holes (BHs). The nature of these mass gap objects is unknown, as is the formation of their host binary systems. We report pulsar timing observations made with the Karoo Array Telescope (MeerKAT) of PSR J05144002E, an eccentric binary millisecond pulsar in the globular cluster NGC 1851. We found a total binary mass of 3.887 ± 0.004 solar masses (M⊙), and multiwavelength observations show that the pulsar’s binary companion is also a compact object. The companion’s mass (2.09 to 2.71 M⊙, 95% confidence interval) is in the mass gap, indicating either a very massive NS or a low-mass BH. We propose that the companion formed in a merger between two earlier NSs.
Source: https://www.science.org/doi/10.1126/science.adg3005