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In this issue:
From Paul Golan: Accident Reporting
SLAC at the LHC: Computing and Data Services
Word of the Week: Plerion
Building the LCLS: Weekly Update

SLAC Today

Friday - September 5, 2008

(Photo - Paul Golan)

From Paul Golan: Accident Reporting

It has been a year since I came to SLAC as the Stanford Site Office manager and it has been an amazing year for the laboratory. I would like borrow Persis’s weekly column to provide feedback on what I have seen regarding safety at SLAC. First, congratulations to the Linac Coherent Light Source team; over the last 145 days, they have had only one reportable injury despite a massive amount of work completed—including the pouring of 5000 yards of concrete, energization of high voltage switch gear, and testing of many newly installed utility systems. My challenge to the LCLS team is to complete construction without another accident or injury.

At last October’s Safety and Security briefing, I challenged each of you to work the entire year without an injury. The good news is most of you met that challenge; with less than a month to go in the fiscal year, we have had twenty-one reportable injuries, which is one-third fewer than we saw at this time in FY07. That means more than 1400 of you had no injuries. I am seeing a greater awareness of hazards. I am seeing more managers in the field on a routine basis. I am seeing more people looking after their co-workers. In short I am seeing a lot of good, reinforcing behaviors. Thank you for making it a safer year and keep up the good work… we can continue to do better!  Read more...

SLAC at the LHC: Computing and Data Services

Not all of the Large Hadron Collider's hardware resides on the French/Swiss border; SLAC is playing a role in data analysis for the LHC's ATLAS detector right here on site. As a Tier 2 computing center, the lab has an integral part in the global effort to analyze the onslaught of data expected from ATLAS once the LHC comes online. SLAC is one of a few dozen Tier 2 institutions around the world, and one of only five in the U.S. At the moment, the main job of a Tier 2 institution is to run collision simulations. Once the LHC turns on, the lab's role will expand to include interpreting the data in search of a deeper understanding of physics at high energies.

"Intense data analysis is always a computing challenge," said Richard Mount, director of Scientific Computing Services and principal investigator for SLAC's Tier 2 project. "The unprecedented scale of BaBar physics analysis and our forward-looking work such as PetaCache, which involves massive random-access memory, have positioned us to create an agile and innovative environment for ATLAS analysis."

The tiered grid computing system enables the distribution and organization of the LHC's vast data and computing resources. CERN, the Tier 0 institution, will conduct the first round of data collection. The data will then find their way to one of the 10 Tier 1 institutions around the world, including Brookhaven National Laboratory—the only such site in the U.S.—for reconstruction of raw data into useful information such as particle energy and momentum. After multiple rounds of further Tier 1 refinement, the data are ready for Tier 2 computing centers like SLAC, which will provide researchers with the computing power they need to begin analysis for their particular projects.  Read more...

Word of the Week:

The Crab Nebula is a plerion powered by an energetic pulsar.
(Image courtesy NASA.
Click for larger image.)

A plerion—a celestial object also known as a "pulsar wind nebula"—is an immense cloud of glowing gas powered by an energetic pulsar, often found within the remnants of a supernova. Unlike other nebulae, plerions appear not as expanding shells of gas but as clouds with filled centers, glowing with the synchrotron radiation of high-energy particles emitted by their pulsars. Plerions are also a source of gamma rays, which are of interest to scientists using the Fermi Gamma-ray Space Telescope to study both pulsars and any surrounding pulsar wind nebulae.

Building the LCLS: Weekly Update

Construction highlights from the Linac Coherent Light Source this week include:

• Fire alarm and pager system testing throughout the LCLS facility, which will continue for another two weeks

• Emergency lighting in the Beam Dump and the Front End Enclosure

• Grounding installations at the Access Tunnel entrance

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