Doug Finkbeiner on #DarkMatter & the Galactic Center

We had a visit recently from Doug Finkbeiner (Harvard CfA), talking about his recent work looking at a possible detection of gamma-ray line emission from the Galactic Center. But is it dark matter?


  1. Prologue

    On Friday morning, my former officemate, Andrew Pontzen, tweeted about the paper Doug and his former student Meng Su (@FermiBubble) recently posted on the arxiv. Coincidentally, Doug Finkbeiner was at that very moment making his way to the Institute of Astronomy to give a talk and be my officemate for the day.
  2. Brooke seconded the request.
  3. Science!

  4. Several hours passed. Doug gave his talk, and we went for lunch with a bunch of people and discussed new observational tests that could be done, possible implications, theoretical issues, etc. It was a fun day! Talking about physics with clever people is pretty much my favorite part of my job. (Finding bugs in code, which was most of my job this week... not so high up on the list.)
  5. At this point in the tweeting, Ethan Siegel pointed out an interesting discovery neither Doug nor I had heard of ...
  6. Turns out there's a source of high-energy radiation close to the Galactic Center that appears to have line-emission at 511 keV (according to one observatory, at least). That's the right energy to be electron-positron annihilation, hence the name Great Annihilator. But it's a point source and apparently has jets, so it's probably some kind of black hole rather than a dark matter-related thing. (See also: