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In this issue:
Muon Makes Tracks in EXO-200 Detector
Einstein's Universe: the Scientist, the Man, the Musician
Colloquium Today: Accelerator Frontiers—Where Can We Go

SLAC Today

Monday - January 31, 2011

Muon Makes Tracks in EXO-200 Detector

(Image - muon traces)
These four lines show four different views of a single muon track, captured during initial tests of the EXO-200 detector. One track appears in each of four measurement channels and shows variations in signal strength from lower (blue and green) to higher (red) intensities over time (left to right). The timing with which each channel receives the signal allows EXO researchers to deduce the location of the track inside the detector chamber. (Image courtesy the EXO team.)

The Enriched Xenon Observatory-200, a prototype observatory that will search for exotic decays of fundamental particles of matter, passed a significant if unofficial milestone last month: its detector registered the track of a cosmic-ray muon.

"For the first time we have everything going underground," said SLAC physicist and EXO collaboration member Marty Breidenbach. During commissioning of the experiment in the final two months of last year, the team filled EXO's central chamber with liquid xenon and tested the full experimental setup for the first time.

EXO-200 will use a detector filled with 200 kilograms of liquid xenon to detect a type of particle decay known as neutrinoless double-beta decay. Neutrinoless double-beta decay has been predicted but never seen. Seeing it—or even not seeing it within a certain time period—can help place bounds on the mass of the neutrino, that miniscule particle that streams through most matter, including us, by the billions each second with nary a clue.  Read more...

(Image - event flyer)

Einstein's Universe:
The Scientist, the Man, the Musician

On Wednesday, February 23 at 7 p.m., SLAC National Accelerator Laboratory will host a performance of Einstein's Universe: The Scientist, the Man, the Musician, presented by physicist Brian Foster and musician Jack Liebeck. This free special lecture, interspersed with classical music, explores Einstein's legacy to physics and the role music played in his life.

After the 90-minute performance, guests will have an opportunity to speak to the performers and enjoy refreshments.

Although the event is free, seating is limited and advance registration is required. Register at

Individuals may register themselves and up to four guests. Upon arrival at SLAC, guests will be directed to parking and to the performance auditorium. All adults (18 and older) are required to show a valid photo ID at the Main SLAC Gate upon entrance.

If you have any questions, please contact Pat Kreitz, 650-926-4385.

Colloquium Today:
Accelerator Frontiers—Where Can We Go

(Image - SLAC Colloquium banner)

Today at 4:15 p.m. in Panofsky Auditorium, CERN accelerator scientist Ralph Assmann will present a colloquium, "Accelerator Frontiers—Where Can We Go," presenting selected results from state-of-the-art accelerators. The observations illustrate the high level of excellence reached in accelerator science and technology but also some of the limitations encountered. Assmann will discuss how novel acceleration methods may allow building a new generation of particle accelerators. Thoughts on required R&D and important milestones will be presented .

The event is free and open to all.




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