KITP: grb

long weekend over, and we're back at it.
today's topic is GRBs
and what, you might ask, do they have to do with clusters...?

Well, Bob, as you know, there are two types of gamma-ray bursters, or maybe three depending on how you count
type I and type II the long and the short

"Some say" that short gamma-ray bursts are, clearly, coalescing binary neutron stars, spiraling into contact through gravitational radiation emission.
This can, clearly, happen in globular clusters, as evidenced by PSR M15C, and taking a single data point, inverting the rate, and throwing in some theoretical guesstimates leads one to conclude that somewhere between 10% and 100% of the short GRBs come from clusters or binary neutron stars that used to be in clusters but got ejected.
Except, it can't be 100% because we see several merging binary neutron stars in the field in the Milky Way which contribute strongly to the mean-rate-per-galaxy, so maybe it is more like 10-30% of the total rate.

and I appear to have lost about an hour of typing of notes on the discussion... argh

the "long" discussion was quite interesting also at that. sigh.
Will try to recreate something, already behind on things.