Speaker
Dr
Roberto Soria
(ICRAR-Curtin University)
Description
Determining the power output and efficiency of accreting black holes is a fundamental astrophysical problem:
we want to know the relation between mass accretion rate, radiative output (photons) and mechanical output
(kinetic energy of jets and winds). We focus in particular on off-nuclear black holes that are accreting
from a donor star at a rate near or above the critical Eddington limit. Many of them appear as "ultraluminous
X-ray sources", evidence of their high radiative output. But how much additional power is carried by winds and jets?
To answer this question, we studied a sample of powerful black holes associated with large bubbles of shock-ionized
and/or photo-ionized gas. We used the bubbles as calorimeters to measure the power injected by the black hole
into its surroundings. We find that black holes at super-Eddington accretion rates can have a mechanical power
comparable to their radiative luminosity. Our study provides empirical constraints for theoretical models
of super-Eddington accretion, and for models of black hole feedback in the early universe.
Primary author
Dr
Roberto Soria
(ICRAR-Curtin University)
Co-authors
Dr
Christian Motch
(University of Strasbourg)
Dr
Fabien Grise'
(University of Strasbourg)
Dr
James Miller-Jones
(ICRAR-Curtin University)
Prof.
Manfred Pakull
(University of Strasbourg)
