We characterise the population of wandering black holes, defined as those physically offset from their halo centres, in the Romulus cosmological simulations. Unlike most other currently available cosmological simulations, black holes are seeded based on local gas properties and are permitted to evolve dynamically without being fixed at halo centres. Tracking these black holes allows us to make robust predictions about the offset population. We find that the number of wandering black holes scales roughly linearly with the halo mass, such that we expect thousands of wandering black holes in galaxy cluster halos. Locally, these wanderers account for around 10 per cent of the local black hole mass budget once seed masses are accounted for. Yet for higher redshifts ($z\gtrsim 4$), wandering black holes both outweigh and outshine their central supermassive counterparts. Most wandering black holes, we find, remain close to the seed mass and originate from the centres of previously disrupted satellite galaxies. While most do not retain a resolved stellar counterpart, those that do are situated farther out at larger fractions of the virial radius. Wanderers with higher luminosities are preferentially at lower radius, more massive, and either closer to their host's mid-planes or associated with a stellar overdensity. This analysis shows that our current census of supermassive black holes is incomplete and that a substantial population of off-centre wanderers likely exists.
Wandering intermediate-mass black holes and off-nuclear tidal disruption events from early star clusters
Carnegie Mellon University(卡内基梅隆大学);Massachusetts Institute of Technology(麻省理工学院);Philipps Universität Marburg(马尔堡菲利普斯大学);Rutgers, The State University of New Jersey(罗格斯大学);Flatiron Institute(平顿研究所);The University of Tokyo(东京大学);Kavli Institute for the Physics and Mathematics of the Universe (WPI)(宇宙物理与数学研究 Kavli 研究所)
Probing the origins. III. Exoplanet demographics across Galactic birth radii
Universidad de Alcalá(阿尔卡拉大学);Pontificia Universidad Católica de Chile(智利天主教 Pontificia 大学);Instituto de Astrofísica, Pontificia Universidad Católica de Chile(智利天主教 Pontificia 大学天体物理研究所);Centro de Astrobiología (CAB) CSIC-INTA(CSIC-INTA 天体生物学中心);European Space Agency (ESA), European Space Astronomy Centre (ESAC)(欧洲空间局(ESA)欧洲空间天文中心);Nicolaus Copernicus Astronomical Center, Polish Academy of Sciences(波兰科学院尼古拉·哥白尼天文中心)
TDE 2025abcr: A Tidal Disruption Event in the Outskirts of a Massive Galaxy
University of Maryland(马里兰大学);NASA Goddard Space Flight Center(NASA戈达德太空飞行中心);University of North Carolina at Chapel Hill(北卡罗来纳大学教堂山分校);The Pennsylvania State University(宾夕法尼亚州立大学);University of California, Berkeley(加州大学伯克利分校)
Seeds to success: growing heavy black holes in dense star clusters
Gran Sasso Science Institute (GSSI)(格兰萨索科学研究所);INFN, Laboratori Nazionali del Gran Sasso(意大利国家核物理研究所,格兰萨索国家实验室);Universität Heidelberg, Zentrum für Astronomie (ZAH), Institut für Theoretische Astrophysik(海德堡大学天体物理中心(ZAH),理论天体物理学研究所)