LIGO’s second gravitational wave makes it official: merging black holes don’t burst (Synopsis)

“If you’ve seen one gamma-ray burst, you’ve seen one gamma-ray burst!” -Common quote among gamma-ray burst astronomers, emphasizing how little we know about them.

When the first gravitational wave signal ever, GW150914, was directly detected, NASA’s Fermi GBM team shocked the world by announcing the detection of a high-energy burst of electromagnetic radiation. This was a huge surprise, because merging black holes shouldn’t have a bright gamma ray or X-ray flash associated with them!

Image credit: NASA, of an inspiral and merger of two massive, compact objects; illustration only.

A statistical reanalysis and the ESA’s INTEGRAL satellite both failed to confirm it, but it would take a second event to know for certain. With GW151226 now in the books, a look through the Fermi GBM data shows what we suspected all along: black holes DON’T burst when they merge!

A double black hole, which would require an incredibly unlikely scenario to produce high-energy radiation. Image credit: Image credit: NASA, ESA and G. Bacon (STScI).

1. #1 See Noevo
June 16, 2016

Just a thought that came into my head…

Ethan has quite an interest in black holes.
Four of his last nine articles are about them.
If it’s not a fondness, it’s certainly a fascination and acceptance.

Which is somewhat ironic.
Black holes are really quite “mean” and “unforgiving”. *Anything* that was to go into a black hole NEVER gets out. Even if it’s an “innocent” beam of light.
*Even if* it’s an *innocent* you.
You NEVER will get out.

It’s quite a concept.
I say ironic because I’m pretty confident Ethan would have no similar interest in, nor acceptance of, the concept of Hell.

June 16, 2016

I say ironic because I’m pretty confident Ethan would have no similar interest in, nor acceptance of, the concept of Hell.

How does Hell’s evaporative timescale compare with $latex t=8.4\times10^{-17}M^3$ s?

3. #3 Michael Kelsey
SLAC National Accelerator Laboratory
June 16, 2016

@Deceiver #1: “Ironic”? It’s his _job_, you bloody imbecile. Ethan is a professional astrophysicist.

You, on the other hand, must have an inordinate fondness (or at least a fascination and acceptance), for the underside of bridges.

4. #4 Omega Centauri
June 16, 2016

Ethan, I suspect merging BH with accretion disks have been modeled. Just how much mass would need to be in the disk(s) to make a signal detectable at 1.e9 lightyears?

5. #5 dean
June 17, 2016

I say ironic because I’m pretty confident Ethan would have no similar interest in, nor acceptance of, the concept of Hell.

Not ironic at all (even as you don’t seem to know the meaning of ironic). Ethan is, after all, a scientist, and so has a reason to be interested in the sorts of things science, especially his area of science, studies.

On the contrary, the hell to which you refer is the stuff of mythology, dragged out to scare children and the weak-minded in order to keep them in line.

6. #6 Naked Bunny with a Whip
June 17, 2016

It’s possible that Ethan would write about Hell if theologians ever got around to defining what Hell is, building a Hell detector, and successfully recording the screams of the damned.