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In this issue:
More Magnetic Milestones in the MMF
Safety Today: PCD is PCB Free
Princess Sumaya of Jordan Visits SLAC

SLAC Today

Tuesday - January 22, 2008

More Magnetic Milestones in the MMF

The first LCLS undulator to be mounted to its girder, shown here atop the coordinate measuring machine in SLAC's Magnetic Measurement Facility.

Last week, undulator work in SLAC's Magnetic Measurement Facility (MMF) for the Linac Coherent Light Source (LCLS) entered a new chapter as workers for the first time mated an undulator with the girder to which it will eventually be mounted in the Undulator Hall (UH). This marks a further step toward the beginning of installation, scheduled to begin in the next few months as work on the UH nears completion.

As one would expect of a machine as complex as the LCLS, pairing an undulator and girder is a bit more complicated that simply tightening a few bolts. Each undulator weighs 1,800 pounds, and the girders weigh 2,600 pounds—but despite that degree of heft, the interface between the two must be precise down to 20 microns, or one-fifth the width of a human hair. Verifying the precision machining of the girders, which will be mounted permanently to their stands in the UH, is critical to ensuring the undulators may be swapped as needed without having to dismantle the beam pipe. The beam pipe itself will also be secured to the undulator girders.

"We're working very hard to certify the undulators conform to the optimal design specifications, and this is one more step toward completing that job," said Metrology Department team leader Eric Lundahl. "It's exciting to see the LCLS moving forward."

(Column - Safety Today)

PCD is PCB Free

Recently, SLAC took yet another step toward becoming a greener and safer laboratory.

When SLAC was first built in the 1960s, polychlorinated biphenyls (PCBs) were used in enclosed electrical components. At the time of construction, the health risks of PCBs were not generally known and the synthetic chemical compound was used in a wide range of industrial and consumer products. Since the mid-1970s, toxicology evidence showed that PCBs can accumulate in the environment and can cause harmful effects (see a Department of Health and Human Services summary).

PCBs around SLAC are contained in enclosed components, reducing the risk of exposure and harmful effects. The Power Conversion Department (PCD) and the Environmental, Safety and Health (ES&H) Division recently made further significant progress in removing many of these components to further ensure the safety of lab staff who might have to interact with them directly. 

The project, which was initiated by ES&H's Mike Hug and coordinated by PCD's Jim Craft, completed removing the last of the PCBs from the Klystron Modulators in the klystron gallery last October. As a result, the PCD is now PCB free.

“It pleases us all that we were able to make the klystron gallery, which is an inherently hazardous area, even safer,” said Craft.

To do this, the Power Conversion Department’s Power Electronics Maintenance (PEM) group under the management and supervision of Craft, Serge Ratkovsky and Lou Fernandez removed all klystron-modulator AC input filters containing PCBs—492 of them in all—during this year's shutdown. These old filters, which were about the size of a soda can, were replaced with modern, non-PCB units.  Read more...

Princess Sumaya of Jordan Visits SLAC

Herman Winick and Princess Sumaya bint El Hassan of Jordan in SSRL. (Click on image for larger version.)

Her Royal Highness Princess Sumaya bint El Hassan of Jordan visited SLAC last Friday for a tour of the lab and meetings with researchers. The Princess plays a major role in education, science, and technology in Jordan. For example she is the head of the Princess Sumaya University for Technology (PSUT) Board of Trustees and the President of the Royal Scientific Society (RSS).

She came to SLAC primarily to see SSRL in operation as a model for SESAME (Synchrotron-light for Experimental Science and Applications in the Middle East), a UNESCO sponsored project in construction in Jordan as a collaboration among 10 Middle East countries.

After meeting with Persis Drell and other directorate members, Princess Sumaya toured the laboratory with Keith Hodgson and host Herman Winick, who, along with Gus Voss of DESY, initiated the SESAME Project in 1997. Uwe Bergmann explained how x-rays can be used to read overwritten ancient manuscripts, and Les Cottrell talked about the digital divide with emphasis on the Middle East. After visiting SLAC she had lunch with President Hennessy and Art Bienenstock. Following this she gave a talk and had spirited exchanges with Stanford faculty and students at the Center for Democracy, Development and the Rule of Law on the Stanford campus.

"In her interactions she proved to be charming, as well as articulate about the problems in Jordan and the Arab world in general while describing her activities and ideas about addressing them with science and technology," said Winick. "Many thanks to everyone who helped with her visit."


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