Tidal disruption of a super-Jupiter by a massive black hole
Is it possible to detect an object as small as a planet in an external
galaxy?
Yes, when such an object orbits too close to a massive black hole, it
could be disrupted by the tidal forces induced by the strong gravitational
field and part of the debris may subsequently fall into the black hole,
emitting a strong burst of high-energy radiation.
This is exactly what INTEGRAL discovered at the beginning of 2011 in NGC 4845,
a galaxy never detected in the X-rays before. The shape of the hard X-ray
light curve, measured by the INTEGRAL IBIS/ISGRI, followed the predictions
for such an event (see below).
The top image shows an optical image of NGC 4845 with the error circles
showing the position of the X-ray source as observed by XMM-Newton EPIC-pn,
right at the center. The figure at the bottom shows the light-curve observed
by INTEGRAL IBIS/ISGRI (red data points), XMM-Newton EPIC-pn and Swift XRT
(blue data points). The long-short dash line indicates the prediction of
hydrodynamical simulations for the disruption of a sub-stellar object,
whereas the dotted line shows what would be expected for a disrupted star.
The most probable mass of the disrupted object is 14-30 Jupiter mass. Only
a small fraction (about 10%) of that mass did fall into the black hole.
Credits: Marek Nikołajuk and Roland Walter
Further information:
"Tidal disruption of a super-Jupiter by a massive black hole",
M. Nikołajuk & R. Walter
Published in 2013,
A&A 552, A75
