ELFT HÍRADÓ

[Bence Kocsis <bkocsis AT caesar.elte.hu>]

GALNUC Seminar

Tuesday, March 20, 2018, 4:00 p.m.
Eotvos Lagymanyos campus, Pazmany Peter s. 1/A, room 3.139

speaker:  Ákos Szölgyén (ELTE)

Black hole disk in galactic nuclei

The stellar population of the Milky Way's center shows a striking
complexity. The old low-mass stars are observed to be spherically
distributed while young massive stars form a disk within the nuclear star
cluster. This structure is also apparent in other galaxies, however, the
origin of the observed distribution is controversial. In the next GalNuc
seminar, I review the possible formation scenarios and observed structure
of the nuclear star cluster. I explain the hierarchy of gravitational
effects which are responsible for the structure formation. I discuss our
recent work, submitted to PRL, in which we found that the massive stars and
stellar mass black holes (BHs) form a warped disk, while low mass stars
resemble a spherical distribution with a possible net rotation. This
explains the origin of the clockwise disk in the Galactic center and
predicts a population of BHs embedded within this structure. The rate of
mergers among massive stars, tidal disruption events among BHs and massive
stars, and BH-BH mergers are highly increased in such disks. The first two
may explain the origin of the observed G1 and G2 clouds, the latter may be
important for gravitational wave detections with LIGO and VIRGO. More
generally, black holes are expected to settle in disks in all spherical
dense stellar systems including globular clusters.

This is a major milestone of the GALNUC project.

Everyone is welcome!