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In this issue:
Symmetry: New Life for a Linac
Safety Today: Why Track Close Calls?
Reminder: Public Lecture Tonight
SLAC Walk & Run
Safety Second

SLAC Today

Tuesday - October 24, 2006

(Image - LCLS visualizations)
Four views of a 3-D model of the linac and the Linac Coherent Light Source (LCLS). (Images courtesy of Greg Stewart.)

symmetry: New Life for a Linac

Forty-year-old scientific equipment tends to live in storage closets, recycling yards, or the occasional museum. However, the 3-kilometer-long Stanford Linear Accelerator, built in 1966, is merely reaching middle age.

Still doing what it knows best—boosting bunches of electrons to near the speed of light—the linear accelerator, or "linac" to its friends, will soon start a new stage of life. As the source of electrons for a new type of laser, it will be able to see materials, atoms, and molecules, in a completely new way, illuminating new vistas on clean energy, medicine, nanotechnology, and planetary science.

The linac already has an impressive résumé. At the top of the list, no doubt, are the three Nobel prizes it helped to win. It has contributed to a surprisingly wide range of experiments in particle physics, astrophysics, photon science, high-energy nuclear physics, and accelerator science. It also holds a number of titles, such as longest linac and first linear collider.  Read more in symmetry...

(Column - Safety Today)

Why Track Close Calls?

(Photo - space shuttle)In 1986 the Space-Shuttle Challenger exploded soon after lift-off due to faulty o-rings. Engineers working on the shuttle had, previous to the accident, noted that that some of the o-rings used in other shuttle missions were degrading. Management had been informed the night before the launch of Challenger for the potential for such failure.

Was previous reporting of the o-ring degradation a Close Call?

A Close Call is defined as an unplanned sequence of events that could have caused harm if conditions were different or are allowed to progress, but did not in this instance.

In hindsight, this disaster may have been prevented.

Why track Close Calls? The behaviors and conditions that lead to actual accidents and injuries are the same as those involved in Close Calls. If we can get an idea of what almost happened, we can help prevent accidents and injuries that do happen. This is a much cheaper method of prophylaxis (both in terms of human and financial costs).

The Safety Pyramid

In 1931, H.W. Heinrich reported on a study of accidents that he classified according to severity. Heinrich's report showed that for each serious-injury incident, we could expect about 29 minor injuries and 300 Close Call or property-damage incidents, as represented in the above diagram.  Read more...

Reminder: Public
Lecture Tonight

In tonight's public lecture, SLAC's Eduardo do Couto e Silva will discuss the most dramatic of all events in our universe. Come experience "The Violent Universe" this evening at 7:30 p.m. in Panofsky Auditorium.  Learn more...

SLAC Walk & Run

This year's SLAC Run and Walk will take place on Thursday, November 16th at 12:00 p.m.

Due to construction on the north side of Klystron Gallery road, the course will be slightly different than in years past, beginning and ending on the south side of the gallery. The runners' course length is officially 3.8 miles plus 66.5 feet, while the walkers travel two miles. A map of the course will be provided at the event.

Registration starts at 11:45 a.m. on the south side of the Klystron Gallery at Sector 30, and the run starts at 12:05 p.m. sharp. For complete details, visit the Run and Walk website.

Safety Seconds

In yesterday's edition, I asked you to remember the most extreme case of inattentive driving you have ever witnessed.

About five months ago, I saw a woman making a turn at a light in a crowded suburban neighborhood with a cell phone in one hand and a coffee cup in the other: basically driving with no hands. She was not going my way, so I am pretty sure she was not a SLAC staff member, but it's important for all of us to remember that paying attention to the task at hand—no matter how many other tasks plead for our attention—is necessary to stay safe.

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