Bibliographic Details
| Title: |
Origin of high dark remnant fractions in Milky Way globular clusters: the crucial role of initial black hole retention. |
| Authors: |
Rostami-Shirazi, Ali1 (AUTHOR), Baumgardt, Holger2 (AUTHOR), Zonoozi, Akram Hasani1 (AUTHOR), Ghasemi, S Mojtaba1 (AUTHOR), Haghi, Hosein1 (AUTHOR) |
| Source: |
Monthly Notices of the Royal Astronomical Society. Jan2025, Vol. 536 Issue 2, p1332-1343. 12p. |
| Subject Terms: |
*LOW mass stars, *COMPACT objects (Astronomy), *BLACK holes, *STELLAR mass, *SUPERGIANT stars, *GLOBULAR clusters, *STAR clusters |
| Abstract: |
Comparing the dynamical and stellar masses of Milky Way (MW) globular clusters (GCs) reveals a discrepancy exceeding a factor of 2. Since this substantial invisible mass is concentrated in the cluster centre, it is attributed to stellar remnants. The majority of mass in remnants consists of white dwarfs (WDs). Allocating over half of a GC's current mass to WDs could significantly restrict the dynamical evolution scenarios governing stellar clusters. As the most massive stars in GCs, black holes (BHs) exert a substantial effect on the escape rate of lower mass stars, such as WDs. This paper aims to identify which scenarios of BH natal kicks can accurately reproduce the notable dark remnant fraction observed in MW GCs. We compare the observed remnant fraction of MW GCs with a comprehensive grid of direct N -body simulations while adjusting the natal kick received by BHs. Our results reveal that simulations employing low natal kicks to BHs are the only ones capable of mirroring the remnant fraction of MW GCs. According to the Spitzer instability, the presence of a BH population prompts the formation of a BH sub-system (BHSub) at the centre of a star cluster. The BHSub serves as an energetic power plant, continually releasing kinetic energy through few-body encounters between single and binary BHs, and transferring the generated energy to the entire stellar population. This energy induces a significant difference in the ejection rate of stellar remnants and luminous stars, ultimately increasing the fraction of dark remnants within the star cluster. [ABSTRACT FROM AUTHOR] |
|
Copyright of Monthly Notices of the Royal Astronomical Society is the property of Oxford University Press / USA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) |
| Database: |
Academic Search Complete |
