Tidal Disruption Events and Gravitational Waves from Intermediate-mass Black Holes in Evolving Globular Clusters across Space and Time

ABSTRACT The dynamical formation of black hole binaries in globular clusters that merge due to gravitational waves occurs more frequently in higher stellar density. Meanwhile, the probability to form intermediate mass black holes (IMBHs) also increases with the density. To explore the impact of the formation and growth of IMBHs on the population of stellar mass black hole binaries from globular clusters, we analyse the existing large survey of Monte Carlo globular cluster simulation data (mocca-survey Database I). We show that the number of binary black hole mergers agrees with the prediction based on clusters’ initial properties when the IMBH mass is not massive enough or the IMBH seed forms at a later time. However, binary black hole formation and subsequent merger events are significantly reduced compared to the prediction when the present-day IMBH mass is more massive than ${\sim}10^4\, \rm M_{\odot }$ or the present-day IMBH mass exceeds about 1 per cent of cluster’s initial total mass. By examining the maximum black hole mass in the system at the moment of black hole binary escaping, we find that ∼90 per cent of the merging binary black holes escape before the formation and growth of the IMBH. Furthermore, large fraction of stellar mass black holes are merged into the IMBH or escape as single black holes from globular clusters in cases of massive IMBHs, which can lead to the significant underpopulation of binary black holes merging with gravitational waves by a factor of 2 depending on the clusters’ initial distributions.

Download Full-text

Intermediate-mass black holes in globular clusters: observations and simulations - Update

Proceedings of the International Astronomical Union ◽

10.1017/s1743921315010601 ◽

2015 ◽

Vol 12 (S316) ◽

pp. 240-245

Author(s):

Nora Lützgendorf ◽

Markus Kissler-Patig ◽

Karl Gebhardt ◽

Holger Baumgardt ◽

Diederik Kruijssen ◽

...

Keyword(s):

Black Holes ◽

Black Hole ◽

Globular Clusters ◽

Galactic Center ◽

Early Stage ◽

Life Time ◽

Intermediate Mass ◽

Software Environment ◽

Integral Field ◽

Intermediate Mass Black Holes

AbstractThe study of intermediate-mass black holes (IMBHs) is a young and promising field of research. If IMBH exist, they could explain the rapid growth of supermassive black holes by acting as seeds in the early stage of galaxy formation. Formed by runaway collisions of massive stars in young and dense stellar clusters, intermediate-mass black holes could still be present in the centers of globular clusters, today. We measured the inner kinematic profiles with integral-field spectroscopy for 10 Galactic globular cluster and determined masses or upper limits of central black holes. In combination with literature data we further studied the positions of our results on known black-hole scaling relations (such as M• − σ) and found a similar but flatter correlation for IMBHs. Applying cluster evolution codes, the change in the slope could be explained with the stellar mass loss occurring in clusters in a tidal field over its life time. Furthermore, we present results from several numerical simulations on the topic of IMBHs and integral field units (IFUs). N-body simulations were used to simulate IFU data cubes. For the specific case of NGC 6388 we simulated two different IFU techniques and found that velocity dispersion measurements from individual velocities are strongly biased towards lower values due to blends of neighbouring stars and background light. In addition, we use the Astrophysical Multipurpose Software Environment (AMUSE) to combine gravitational physics, stellar evolution and hydrodynamics to simulate the accretion of stellar winds onto a black hole. We find that the S-stars need to provide very strong winds in order to explain the accretion rate in the galactic center.

Download Full-text

Radio observations of NGC 2808 and other globular clusters: constraints on intermediate-mass black holes

Monthly Notices of the Royal Astronomical Society ◽

10.1111/j.1365-2966.2008.13577.x ◽

2008 ◽

Vol 389 (1) ◽

pp. 379-384 ◽

Cited By ~ 43

Author(s):

Thomas J. Maccarone ◽

Mathieu Servillat

Keyword(s):

Black Holes ◽

Globular Clusters ◽

Radio Observations ◽

Intermediate Mass ◽

Intermediate Mass Black Holes

Download Full-text

GLOBULAR CLUSTERS HOSTING INTERMEDIATE-MASS BLACK HOLES: NO MASS-SEGREGATION BASED CANDIDATES

The Astrophysical Journal ◽

10.3847/0004-637x/823/2/135 ◽

2016 ◽

Vol 823 (2) ◽

pp. 135 ◽

Cited By ~ 6

Author(s):

Mario Pasquato ◽

Paolo Miocchi ◽

Sohn Bong Won ◽

Young-Wook Lee

Keyword(s):

Black Holes ◽

Globular Clusters ◽

Intermediate Mass ◽

Mass Segregation ◽

Intermediate Mass Black Holes

Download Full-text

Synthetic extinction maps around intermediate-mass black holes in Galactic globular clusters

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stw1095 ◽

2016 ◽

Vol 460 (3) ◽

pp. 2542-2551 ◽

Cited By ~ 2

Author(s):

C. Pepe ◽

L. J. Pellizza

Keyword(s):

Black Holes ◽

Globular Clusters ◽

Intermediate Mass ◽

Galactic Globular Clusters ◽

Intermediate Mass Black Holes

Download Full-text

Observational evidence for intermediate-mass black holes

International Journal of Modern Physics D ◽

10.1142/s021827181730021x ◽

2017 ◽

Vol 26 (11) ◽

pp. 1730021 ◽

Cited By ~ 84

Author(s):

Mar Mezcua

Keyword(s):

Black Holes ◽

Galaxy Formation ◽

Globular Clusters ◽

High Redshift ◽

Galactic Nuclei ◽

Observational Evidence ◽

Intermediate Mass ◽

X Ray ◽

Mass Scaling ◽

Intermediate Mass Black Holes

Intermediate-mass black holes (IMBHs), with masses in the range [Formula: see text]–[Formula: see text][Formula: see text]M[Formula: see text], are the link between stellar-mass BHs and supermassive BHs (SMBHs). They are thought to be the seeds from which SMBHs grow, which would explain the existence of quasars with BH masses of up to 10[Formula: see text][Formula: see text]M[Formula: see text] when the Universe was only 0.8 Gyr old. The detection and study of IMBHs has thus strong implications for understanding how SMBHs form and grow, which is ultimately linked to galaxy formation and growth, as well as for studies of the universality of BH accretion or the epoch of reionization. Proving the existence of seed BHs in the early Universe is not yet feasible with the current instrumentation; however, those seeds that did not grow into SMBHs can be found as IMBHs in the nearby Universe. In this review, I summarize the different scenarios proposed for the formation of IMBHs and gather all the observational evidence for the few hundreds of nearby IMBH candidates found in dwarf galaxies, globular clusters, and ultraluminous X-ray sources, as well as the possible discovery of a few seed BHs at high redshift. I discuss some of their properties, such as X-ray weakness and location in the BH mass scaling relations, and the possibility to discover IMBHs through high velocity clouds, tidal disruption events, gravitational waves, or accretion disks in active galactic nuclei. I finalize with the prospects for the detection of IMBHs with up-coming observatories.

Download Full-text