Western University, London, Ontario, Canada | 2019 Jun 28
Astrophysicists at Western University have found evidence for the direct formation of black holes that do not need to emerge from a star remnant. The production of black holes in the early universe, formed in this manner, may provide scientists with an explanation for the presence of extremely massive black holes at a very early stage in the history of our universe. ...
The model is based on a very simple assumption: supermassive black holes form very, very quickly over very, very short periods of time and then suddenly, they stop. This explanation contrasts with the current understanding of how stellar-mass black holes are formed, which is they emerge when the centre of a very massive star collapses in upon itself. ...
Basu and Das developed the new mathematical model by calculating the mass function of supermassive black holes that form over a limited time period and undergo a rapid exponential growth of mass. The mass growth can be regulated by the Eddington limit that is set by a balance of radiation and gravitation forces or can even exceed it by a modest factor. ...
During the last decade, many supermassive black holes that are a billion times more massive than the Sun have been discovered at high ‘redshifts,’ meaning they were in place in our universe within 800 million years after the Big Bang. The presence of these young and very massive black holes question our understanding of black hole formation and growth. The direct-collapse scenario allows for initial masses that are much greater than implied by the standard stellar remnant scenario, and can go a long way to explaining the observations. This new result provides evidence that such direct-collapse black holes were indeed produced in the early universe. ...
The Mass Function of Supermassive Black Holes in the Direct-Collapse Scenario ~ Shantanu Basu, Arpan Das
- Astrophysical Journal Letters 879(1):L3 (2019 July 01) DOI: 10.3847/2041-8213/ab2646
- arXiv.org > astro-ph > arXiv:1906.05138 > 12 Jun 2019