Short-duration gamma-ray bursts (GRBs) are likely the collision of two neutron stars (or possibly a neutron star-black hole pair), based on the light they emit and the places they occur. Neutron stars are the extremely dense remains of the cores of stars more massive than the Sun; when they collide, they release a lot of energy. Potentially, that energy could lead to nuclear fusion in the material ejected from the explosion, something known (annoyingly) as a kilonova, not to be confused with a supernova, a hypernova, or a bossanova. Researchers may have found signs of a kilonova at the location of a GRB, which if it bears out, would be a promising find — and potentially a new source for some of the heavy nuclei in the Universe.
Astronomers at the Harvard-Smithsonian Center for Astrophysics identified a red point of light at the same location as a powerful explosion known as a short duration gamma-ray burst. This is the first identification of an optical counterpart to this type of gamma-ray burst, and it could be the signature of new neutron-rich elements being produced in the aftermath of the explosion. If that conclusion is correct, then this observation is powerful support for the idea that colliding neutron stars are responsible for many gamma-ray bursts and the origin of some heavy elements. [Read more…]
Now if I can be grumpfy for just a moment, the press release and conference emphasized the production of gold in this explosion. However, no specific signature of gold was mentioned in the research paper; it was merely a plausibility statement, assuming the GRB was a kilonova. Thanks to the emphasis of the press statements, though, most of the media coverage was “colliding neutron stars are the source of all the gold in the Universe!!!!1!!”, which is premature to say the least. It’s also too bad, because I thought the research paper itself was measured and most emphatically didn’t jump to conclusions.