Tuesday, 4 December 2018

Digging in the Stellar Graveyard

Or: double your black holes!

The LIGO and Virgo collaborations have published their catalog of gravitational-wave detections from the first and second observing runs (2015-17). The news: four more binary-black-hole mergers, and the "LIGO-Virgo Transient" from October 2015, LVT151012, now upgraded to a bona fide detection.

That doubles the number of binary-black-hole mergers observed so far: five had been published already, and now we have ten. Along with the binary-neutron-star observation from August 2017, that fits nicely with my rough prediction a few years ago, that we would likely observe ten black-hole mergers for every binary neutron star. Neutron-star mergers might be the furnace that creates gold in our universe, but the real gold rush of gravitational-wave detectors is a bounty of black holes.