Constraining the Black Hole Initial Mass Function with LIGO/Virgo Observations

AbstractWe investigate the dissolution process of star clusters embedded in an external tidal field and harboring a subsystem of stellar-mass black hole. For this purpose we analyzed the MOCCA models of real star clusters contained in the Mocca Survey Database I. We showed that the presence of a stellar-mass black hole subsystem in tidally filling star cluster can lead to abrupt cluster dissolution connected with the loss of cluster dynamical equilibrium. Such cluster dissolution can be regarded as a third type of cluster dissolution mechanism. We additionally argue that such a mechanism should also work for tidally under-filling clusters with a top-heavy initial mass function.

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Critical collapse and the primordial black hole initial mass function

Physical Review D ◽

10.1103/physrevd.60.063509 ◽

1999 ◽

Vol 60 (6) ◽

Cited By ~ 36

Author(s):

Anne M. Green ◽

Andrew R. Liddle

Keyword(s):

Black Hole ◽

Mass Function ◽

Initial Mass Function ◽

Initial Mass ◽

Primordial Black Hole

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Initial mass function of intermediate-mass black hole seeds

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stu1280 ◽

2014 ◽

Vol 443 (3) ◽

pp. 2410-2425 ◽

Cited By ~ 76

Author(s):

A. Ferrara ◽

S. Salvadori ◽

B. Yue ◽

D. Schleicher

Keyword(s):

Black Hole ◽

Mass Function ◽

Initial Mass Function ◽

Initial Mass ◽

Intermediate Mass

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On the black hole content and initial mass function of 47 Tuc

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz2995 ◽

2019 ◽

Vol 491 (1) ◽

pp. 113-128 ◽

Cited By ~ 5

Author(s):

V Hénault-Brunet ◽

M Gieles ◽

J Strader ◽

M Peuten ◽

E Balbinot ◽

...

Keyword(s):

Black Hole ◽

Mass Function ◽

Initial Mass Function ◽

Initial Mass ◽

Low Mass Stars ◽

Evolutionary Origins ◽

History Of ◽

Best Fitting ◽

Low Mass

ABSTRACT The globular cluster (GC) 47 Tuc has recently been proposed to host an intermediate-mass black hole (IMBH) or a population of stellar mass black holes (BHs). To shed light on its dark content, we present an application of self-consistent multimass models with a varying mass function and content of stellar remnants, which we fit to various observational constraints. Our best-fitting model successfully matches the observables and correctly predicts the radial distribution of millisecond pulsars and their gravitational accelerations inferred from long-term timing observations. The data favours a population of BHs with a total mass of $430^{+386}_{-301}$ M⊙, but the most likely model has very few BHs. Since our models do not include a central IMBH and accurately reproduce the observations, we conclude that there is currently no need to invoke the presence of an IMBH in 47 Tuc. The global present-day mass function inferred is significantly depleted in low-mass stars (power-law slope $\alpha =-0.52^{+0.17}_{-0.16}$). Given the orbit and predicted mass-loss history of this massive GC, the dearth of low-mass stars is difficult to explain with a standard initial mass function (IMF) followed by long-term preferential escape of low-mass stars driven by two-body relaxation, and instead suggests that 47 Tuc may have formed with a bottom-light IMF. We discuss alternative evolutionary origins for the flat mass function and ways to reconcile this with the low BH retention fraction. Finally, by capturing the effect of dark remnants, our method offers a new way to probe the IMF in a GC above the current main-sequence turn-off mass, for which we find a slope of −2.49 ± 0.08.

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The global mass functions of 35 Galactic globular clusters – II. Clues on the initial mass function and black hole retention fraction

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stx2036 ◽

2017 ◽

Vol 472 (1) ◽

pp. 744-750 ◽

Cited By ~ 19

Author(s):

H. Baumgardt ◽

S. Sollima

Keyword(s):

Black Hole ◽

Globular Clusters ◽

Mass Function ◽

Initial Mass Function ◽

Initial Mass ◽

Galactic Globular Clusters ◽

Mass Functions ◽

Retention Fraction

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On the Mass Distribution of Stellar-Mass Black Holes

Open Astronomy ◽

10.1515/astro-2017-0190 ◽

2014 ◽

Vol 23 (3-4) ◽

pp. 267-271

Author(s):

O. Yu. Malkov

Keyword(s):

Black Holes ◽

Black Hole ◽

Mass Distribution ◽

Mass Function ◽

Stellar Mass ◽

Initial Mass Function ◽

Initial Mass ◽

Mass Relation ◽

Massive Star Evolution ◽

Remnant Mass

AbstractThe observational stellar-mass black hole mass distribution exhibits a maximum at about 8 M⊙. It can be explained via the details of the massive star evolution, supernova explosions, or consequent black hole evolution. We propose another explanation, connected with an underestimated influence of the relation between the initial stellar mass and the compact remnant mass. We show that an unimodal observational mass distribution of black holes can be produced by a power-law initial mass function and a monotonic “remnant mass versus initial mass” relation.

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The cosmic merger rate density of compact objects: impact of star formation, metallicity, initial mass function and binary evolution

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab280 ◽

2021 ◽

Author(s):

Filippo Santoliquido ◽

Michela Mapelli ◽

Nicola Giacobbo ◽

Yann Bouffanais ◽

M Celeste Artale

Keyword(s):

Black Hole ◽

Star Formation ◽

Neutron Star ◽

Mass Function ◽

Initial Mass Function ◽

Compact Objects ◽

Initial Mass ◽

Common Envelope ◽

Binary Evolution ◽

Merger Rate

Abstract We evaluate the redshift distribution of binary black hole (BBH), black hole – neutron star binary (BHNS) and binary neutron star (BNS) mergers, exploring the main sources of uncertainty: star formation rate (SFR) density, metallicity evolution, common envelope, mass transfer via Roche lobe overflow, natal kicks, core-collapse supernova model and initial mass function. Among binary evolution processes, uncertainties on common envelope ejection have a major impact: the local merger rate density of BNSs varies from ∼103 to ∼20 Gpc−3 yr−1 if we change the common envelope efficiency parameter from αCE = 7 to 0.5, while the local merger rates of BBHs and BHNSs vary by a factor of ∼2 − 3. The BBH merger rate changes by one order of magnitude, when 1σ uncertainties on metallicity evolution are taken into account. In contrast, the BNS merger rate is almost insensitive to metallicity. Hence, BNSs are the ideal test bed to put constraints on uncertain binary evolution processes, such as common envelope and natal kicks. Only models assuming values of αCE ≳ 2 and moderately low natal kicks (depending on the ejected mass and the SN mechanism), result in a local BNS merger rate density within the 90% credible interval inferred from the second gravitational-wave transient catalogue.

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