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In this issue:
Enriched Xenon Observatory: How Clean is Clean?
Changes to Staff Vacation Accrual Policy
Jonathan Dorfan Receives Honorary Degree

SLAC Today

Thursday - January 15, 2009

Enriched Xenon Observatory:
How Clean is Clean?

(Photo - EXO cryo clean)
All parts of the EXO 200 experiment apparatus are thoroughly cleaned before entering a clean room. (Photo courtesy of the EXO experiment. Click for larger image.)

Think you know a neat freak? Even in a field where cleanliness means far more than just washing your hands, the Enriched Xenon Observatory 200 experiment, or EXO 200, is pushing the boundaries of "clean." To ensure that EXO 200 proceeds without interruption, its scientists and engineers must scour the entire experiment for even parts-per-trillion of foreign substances.

The EXO 200 experiment—a prototype for the larger EXO experiment, still in the planning stages—will study neutrinos: subatomic particles that constantly shower down on the earth but interact very little with matter. The experiment's two main goals are to measure the neutrino mass, and find out whether or not neutrinos are their own antiparticle—their own symmetric opposite. To eventually help the larger EXO experiment achieve these goals, EXO 200 scientists will search for a rare process called neutrinoless double beta decay, in which two neutrinos, acting as particle and anti-particle, cancel each other out and disappear. But neutrinoless double beta decay is extremely rare, and EXO 200 can't afford any false signals that foreign particulates would send to the detector.  Read more...

Changes to Staff Vacation Accrual Policy

The university has announced that, starting in 2010, the maximum amount of vacation time that a staff member [including SLAC staff] can accrue will be reduced incrementally over a three-year period. The policy change is intended to help departments and units avoid having to set aside money from their budgets to cover large accruals of time off that aren't used.

In response to the university's need to save costs across campus, the maximum amount of vacation time a staff member can accrue will decrease to 400 hours (50 days), starting on Jan. 1, 2010. Then at the start of the 2011 and 2012 calendar years, the maximum will be lowered to 320 hours and 240 hours, respectively.  Read more from the Stanford Report...

Editor's note: See also Provost John Etchemendy's recent Q&A on budget challenges.

Jonathan Dorfan Receives Honorary Degree

Jonathan and Renée Dorfan at the December 8 University of Cape Town ceremony (right) and 39 years previous at Dorfan's 1969 graduation (left). (Photos courtesy of Jonathan Dorfan.
Click for larger image.)

Last month, Director Emeritus Jonathan Dorfan received an honorary Doctor of Science degree from the University of Cape Town. "The trip brought on a lot of nostalgia," said Dorfan, who graduated from the University of Cape Town with a bachelor's degree in physics and applied mathematics 39 years previous—almost to the day. "It was quite thrilling to come back after that number of years and to be honored in this way."


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