From Symmetry: “Stellar black widows entrap companion stars”

Of the hundreds of objects in the universe emitting gamma rays, two look to be “black widows,” ancient stars extending their lives by sucking in material from companion stars. Stanford physicist Roger Romani is hot on the trail of these extreme stars.

November 27, 2012
Lori Ann White

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Roger Romani

“In its four years in orbit, the Fermi Gamma-ray Space Telescope has found a cosmos teeming with points of gamma-ray light. Newly discovered gamma-ray sources run the gamut from the expected, like supernova remnants and active galactic nuclei, to the surprising, like gamma rays from the sun or Earth-bound lightning strikes.


Fermi

But a considerable percentage of the gamma-ray sources discovered by Fermi can’t be matched up with any type of object, expected or not. Of the more than 1800 sources found by Fermi’s main instrument, the Large Area Telescope, in its first two years of operation, almost a third fell into this category.

These “unassociated objects,” as they’re called, are the ones Stanford physics professor Roger Romani likes to study. Romani, a member of the Kavli Institute for Particle Astrophysics and Cosmology, an institute run jointly by Stanford and SLAC National Accelerator Laboratory, has spent the past few years identifying these sources. He’s found most of them to be common astronomical objects that, for one reason or another, were just a bit more difficult to recognize. Two of them, however, appear to be “black widows,” ancient stars extending their lives by sucking in material from companion stars. And there may be more….”

Read on. It gets very interesting.

See the full article here.

Symmetry is a joint Fermilab/SLAC publication.