Month: January 2021

Our group’s population synthesis simulations — the calculations behind our predictions for gravitational wave sources — require far more computing power than any single institution can provide. To bridge that gap, we initiated Universe@Home, a volunteer computing project run from CAMK PAN on the BOINC platform. Anyone with a spare computer can contribute: the BOINC client runs our binary evolution code in the background whenever the machine is idle, returning results to the project server automatically. Since launching in 2015 — as the first BOINC project ever hosted by a Polish scientific institution — Universe@Home has grown to nearly 30,000 participating computers worldwide.

The science running on these volunteer machines covers the full range of our group’s research interests: formation and merger rates of binary black holes and neutron stars, the origin of ultraluminous X-ray sources, and the construction of synthetic black hole population databases for the Milky Way.

If you would like to contribute, you can create a free account and join at https://universeathome.pl

Supernovae explosions end massive stars lives. It is believed that in these explosions star cores collapse to neutron stars or black holes while outer stellar layers are ejected into cosmic void, creating spectacular expanding shells. With modern telescopes a supernova is discovered pretty much every day. Some of supernovae remnants (these expanding shells) were connected with nearby neutron stars, thus confirming stellar evolution predictions. However, until now not a single supernova was connected with black hole formation. Australian-Polish team makes such connection for a distant (12,000 light years away from Earth) supernova remnant called G323.7-1.0. It appears that within this supernova remnant there is a binary system of two objects known as MAXI J1535-571: unseen small star (maybe twice as massive as our Sun) and a medium size black hole (about 5 times more massive than Sun). The unseen star feeds black hole with matter (from its outer layers) and as this matter spirals into the black hole it radiates in X-rays that are detected by some of our space observatories. Since the black hole is almost right in the center of expanding supernova remnant, and it is at the same distance as supernova, it must be that the supernova has created this black hole in the last 10-20 thousand of years. The team estimated that probability of finding a black hole by chance in the position of this supernova is less than 1 in 1000!

Link to paper:
https://ui.adsabs.harvard.edu/abs/2020arXiv201015341M/abstract