occasional meanderings in physics' brave new world

Name:
Location: New Zealand

Marni D. Sheppeard

## Sunday, June 01, 2008

### Neutrino08 Day 6a

Everyone who goes down to Antarctica to work on IceCube must pass through Christchurch, and it is not surprising that UC has a neutrino physics group, which is led by Jenni Adams. The IceCube talk on Saturday morning was given by S. Klein, who began with a description of the detector: 4800 optical modules on 80 strings reaching down 2450m into the ice at the South Pole. This depth represents roughly 100000 years of atmospheric history, and one can see ancient volcanic eruptions due to dust layers observed in the calibration data. There is also a 1 $\textrm{km}^{2}$ surface array of tanks. When the full detector (IC80) is in operation in 2011 they estimate 200 $\nu$ events per day.

There are a number of trigger systems, for example, the firing of 5 of 7 adjacent optical modules on a single string within $1.5 \mu\textrm{s}$. About 6% of events are considered sufficiently interesting to send north via satellite. IceCube is close to releasing a skymap for IC22, which is about 5 times more sensitive than IC9. Some searches were triggered, including the very bright GRB080119B event, although IceCube only expects 0.1 associated $\nu_{\mu}$ events.

Results: The solar WIMP search found no excess and the AMANDA limits have been improved. The solar outburst of December 13, 2006 indicated no large spectral changes. A preliminary cosmic ray spectrum was shown.

chimpanzee said...

Caltech/BICEP group (Andrew Lange/Caltech), pictures from Christchurch/NZ:

http://www.physicschick.com/pole/index_2008_jan.html

[ interesting picture of Dux restaurant @Chrischurch ]

She's a UIUC alumni (like me), we went to the same high-school (her dad is a UIUC physicist, mom an astronomer). She's friends with Dan G (his dad was a UIUC math professor & co-founder of Wolfram Research, along with Theodore Gray..also an alumni of our high-school), who just finished his PhD @Caltech. I was giving them local tips on amateur-astronomy observing.

Trivia:
UIUC is where M. Gell-Mann spent a summer, & made friends with David Pines (who was best man at his wedding). They later went on to co-found the Santa Fe Inst. I went to high-school w/D. Pines son Jon & daughter Cathy (& a bunch of other Physics prof "academic brats"). I last saw Jon at our 20th HS reunion in '95. I mentioned that "Stanford Geophysics PhD" HS friend of mine in previous posts, his dad was a particle physicist @UIUC (shared an office with SJC, who was J. Schwinger's PhD student). I took SJC's graduate-level group-theory course while working on my PhD. My mother babysits for Thomas Junk family (T. Dorigo refers to him), my parents live only 1 block away.

June 02, 2008 4:24 AM
chimpanzee said...