scholarly journals The effect of cooling on the accretion of circumprimary discs in merging supermassive black hole binaries

2020 ◽  
Vol 499 (2) ◽  
pp. 2836-2844
Author(s):  
Camilo Fontecilla ◽  
Giuseppe Lodato ◽  
Jorge Cuadra

ABSTRACT At the final stages of a supermassive black hole coalescence, the emission of gravitational waves will efficiently remove energy, and angular momentum from the binary orbit, allowing the separation between the compact objects to shrink. In the scenario where a circumprimary disc is present, a squeezing phase will develop, in which the tidal interaction between the disc and the secondary black hole could push the gas inwards, enhancing the accretion rate on to the primary and producing what is known as an electromagnetic precursor. In this context, using 3D hydrodynamic simulations, we study how an adiabatic circumprimary accretion disc responds to the varying gravitational potential as the secondary falls on to the more massive object. We included a cooling prescription controlled by the parameter β = Ωtcool, which will determine how strong the final accretion rate is: a hotter disc is thicker, and the tidal interaction is suppressed for the gas outside the binary plane. Our main results are that for scenarios where the gas cannot cool fast enough (β ≥ 30), the disc becomes thick and renders the system invisible, while for β ≤ 10 the strong cooling blocks any leakage on to the secondary’s orbit, allowing an enhancement in the accretion rate of two orders of magnitude stronger than the average through the rest of the simulation.

2012 ◽  
Vol 756 (1) ◽  
pp. 30 ◽  
Author(s):  
Fazeel Mahmood Khan ◽  
Ingo Berentzen ◽  
Peter Berczik ◽  
Andreas Just ◽  
Lucio Mayer ◽  
...  

2017 ◽  
Vol 847 (1) ◽  
pp. 80 ◽  
Author(s):  
G. Witzel ◽  
B. N. Sitarski ◽  
A. M. Ghez ◽  
M. R. Morris ◽  
A. Hees ◽  
...  

2021 ◽  
Vol 81 (11) ◽  
Author(s):  
Gert Hütsi ◽  
Tomi Koivisto ◽  
Martti Raidal ◽  
Ville Vaskonen ◽  
Hardi Veermäe

AbstractWe show that the physical conditions which induce the Thakurta metric, recently studied by Bœhm et al. in the context of time-dependent black hole masses, correspond to a single accreting compact object in the entire Universe filled with isotropic non-interacting dust. In such a case, accretion physics is not local but tied to the properties of the whole Universe. We show that radiation, primordial black holes or particle dark matter cannot produce the specific energy flux required for supporting the mass growth of the compact objects described by the Thakurta metric. In particular, this solution does not apply to black hole binaries. We conclude that compact dark matter candidates and their mass growth cannot be described by the Thakurta metric, and thus existing constraints on the primordial black hole abundance from the LIGO-Virgo and the CMB measurements remain valid.


Sign in / Sign up

Export Citation Format

Share Document