Sunglasses, black holes, and unsafe partners

July 25, 2008

Oh Proud Day ! I am on the front page of the STFC web site ! This is the “polarised sunglasses see black hole disks” story. Doesn’t seem to have made the Daily Mirror, but has reasonably spread round the Internut, including Skymania, New Scientist, Universe Today, Astronomy Now and Chris Lintott in his American Manifestation . A week ago I was even more excited, as the first draft of the press release had a quote from Keef, saying how important UKIRT was to UK astronomy, but it got changed into a quote by Chris Davis. Better in some ways and a shame in others.The person who deserves nearly all the credit by the way is Makoto Kishimoto, one of the most careful but insightful astronomers I know.

If you can’t afford a subscription to Nature, you can read it on astro-ph. Here is the story. Quasar phenomenon supposedly caused by accretion onto supermassive black holes. Prediction since 1973 that accretion discs should show nu**1/3 spectrum – very blue. In optical-UV you don’t see this, but, well, there are complications. Should be a safer bet in the IR, coming from the outer bits of disc. But in the IR all you can see is the emission from the damned dust on much larger scales. Thinks. Light scattered from the disc is polarised, so maybe measuring the polarised flux shows pure uncontaminated disc ? Ahh .. but dust emission is often polarised too. Rats. But wait ! Some quasars show no polarisation in the broad emission lines.. in which case any polarisation must be caused interior to the BLR … try these.. Bingo. Nu**1/3. Or actually, about nu**0.4. Thirty year old theory finally vindicated. Phew. Sits down with glass of whisky.

So for half of today, when I wasn’t googling for references to black hole sunglasses, I was at a meeting here at SLAC today celebrating the career of ex-SLAC-Director Jonathan Dorfan. He is the man credited with pulling off PEP-II and BaBar, turning SLAC into the B-factory, focusing on CP violation and the matter-anti-matter asymmetry. But years later, he was also the man who swung the ship round to head towards a future of light sources, lasers, and biology. (But also particle astrophysics … GLAST, SNAP, LSST … thats why I’m here folks..).

One of the key talks was by Albrecht Wagner from DESY, here to remind us that actually there was still a bright future for particle physics, and indeed Linear Colliders are back in fashion. Errrr… just a shame that the US and UK seem to have changed their minds and pulled the funding plug. The only tense moment in a warm and cuddly day was when Wagner said that the US should now be considered “an unsafe partner for international projects”. Think I’ll stop there.