Passer au contenu

/ Département de physique

Je donne


Navigation secondaire

Interpreting Sgr A*'s Most Luminous X-ray Flares - Daryl Haggard (McGill University)

Interpreting Sgr A*'s Most Luminous X-ray Flares - Daryl Haggard (McGill University)


Sagittarius A* is the closest example of a supermassive black hole
(SMBH) buried within a dense, massive stellar cluster. Sgr A* is more
than 100 times closer than any other SMBH, and our proximity allows us
to detect emission from its accretion flow in the radio, submillimeter
(submm), near infrared (NIR), and X-ray regimes. These rich
multiwavelength, time-resolved data have the power to probe the physical
processes that underlie rapid flares originating near the black hole's
event horizon. During ambitious Chandra and VLA monitoring campaigns
over the last several years, we have detected the brightest-ever X-ray
flares from Sgr A*. However, despite years of observational and
theoretical study, we do not have a complete, unique model to explain
these high-energy flares, or their relationship to variability at other
wavelengths. Viable models range from the tidal disruption of asteroids
to gravitational lensing to magnetic reconnection, motivating observers
to place tighter constraints on the timing and multiwavelength
properties of these outbursts. X-ray flares may also help us relate Sgr
A* to weakly accreting black holes across the mass spectrum. I will
discuss the possible origins and continuing mysteries surrounding Sgr
A*'s high-energy flares and give a brief update on the Sgr A*/G2



Emplacement : 2900, chemin de la Tour D-460 Montréal H3T 1J6 QC Canada