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In this issue:
Lab Announces New Director and Deputy Director of Particle and Particle Astrophysics
Science Today: ILC Coupler Activities at SLAC
Reminder: Environmental Certificate Ceremony
CEF Takes on the CMMS Cataloguing Challenge

SLAC Today

Thursday - July 5, 2007

Lab Announces New Director and Deputy Director of
Particle and Particle Astrophysics

David MacFarlane (left) and Steve Kahn.
(Click on image for larger version.)

Steven Kahn, the current Deputy Director of the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC), has been named the next Director of Particle and Particle Astrophysics (PPA) at the Department of Energy's Stanford Linear Accelerator Center (SLAC).

David MacFarlane, currently the Assistant Director for Elementary Particle Physics, will take on the role of Deputy Director of Particle and Particle Astrophysics.

"This is clearly a very pressing time for the field and for SLAC, with exciting questions to be answered and real strategy to be developed," said Kahn. " I look forward to working on these challenges with David, while also strengthening the growing overlap with the Laboratory's photon science program in areas including accelerator science, detector R&D and computing."  Read more...

(Daily Column - Science Today)

ILC Coupler Activities

Postdoc Faya Wang at the coupler coaxial test stand in End Station B.

While other labs concentrate on developing superconducting cavities for the International Linear Collider (ILC), SLAC is focusing on the technology needed to power them. In addition to klystron, modulator and radio frequency (RF) distribution development, this effort includes a coupler program. A coupler is basically a coaxial transmission line that connects normal-conducting, air-filled, room-temperature waveguide to each superconducting, evacuated, super-cold accelerator cavity. The couplers are complex devices due to the various requirements imposed on them; they must convert the RF to a coaxial mode, transmit high power (~300 kW), be mechanically flexible for cool-down of one end to 2K (-271° Celsius), have a moveable center conductor, have two windows for redundant vacuum isolation, and be as particulate free as the extremely clean cavities.

The SLAC coupler program, headed by Chris Adolphsen of the ILC Department with collaboration from Brian Rusnak of Lawrence Livermore National Laboratory, has two parts. The first is a series of experiments aimed at understanding how the various coupler pieces impact the RF processing time it takes to reach full power operation with acceptable vacuum. It is hoped that isolating parts and studying the limiting phenomena, such as outgassing, will lead to design improvements.

To this end, a test stand has been built in End Station B, powered by an L-band (1.3 GHz) klystron. It includes two specially designed waveguide-to-coax adaptors between which various test pieces will be installed. The latter are two-foot long tubes with different surface preparations or features, such as bellows. A copper inner conductor is supported inside these. Two large RF windows separate the experimental region from the pressurized input waveguide and load for operation under vacuum. During processing, various signals (RF, electron, pressure, and light) are recorded as the power is increased step-wise in amplitude and pulse width. Results so far with straight stainless steel tubes show a resonant phenomenon known as multipacting, in which electrons repeatedly hit the wall, producing more electrons on each impact. This resonant growth occurs only at certain power levels, and the data show fair agreement with predictions.

The other part of the coupler program involves assembling and processing couplers for the ILC-like cryomodules being assembled at Fermilab in the foreseeable future. For this effort, an ultrasonic bath and a class 10 clean-room (10 particles/ft3 above half a micron) will be installed in Building 6, where assembly of the many coupler parts will take place. After painstaking preparation and assembly, the couplers will be mounted in pairs on a specially designed processing cavity in a support stand. They will then be RF processed (warm), with high power flowing into the processing cavity through one coupler and out through the other, until full power is achieved at an acceptable vacuum level. Processed couplers will be shipped to Fermilab, at a rate of ~30/year, where they will be connected to accelerator cavities.

Reminder: Environmental Certificate Ceremony

Don't forget! Jonathan Dorfan will present the 2007 Environmental Stewardship Champion certificates of recognition at 2:00 p.m. today in the Kavli Auditorium. Refreshments will be served after ceremony. All are invited to attend.

CEF Takes on CMMS Cataloguing Challenge

(Photo - summer students)
Maria Aguaristi and Ryan Auer. (Click on image for larger version.)

When SLAC summer student employee Ryan Auer isn't performing SLAC inspired parodies at Family Day and department barbecues, he can be found searching buildings, climbing ladders and scaling rooftops—all with the proper safety equipment, of course. Auer is on the hunt for HVAC equipment, validating existing data while seeking out unlisted machines. The HVAC data, as part of a larger effort including all SLAC maintenance equipment, will be put into Famis, a Computer Maintenance Management System (CMMS) recently purchased by the Conventional and Experimental Facilities (CEF) department.

Famis will improve the services provided by the CEF department in many ways. It will quickly provide technicians access to information about equipment in need of service. For example, if the air conditioning in an office is not working, Famis can locate all HVAC equipment in the building to help locate the culprit. Technicians will also be able to view the equipment's entire service history in the field on a handheld device.

"The new system will allow maintenance technicians to stay in the field," said Leslie Bachant. "Eventually, we can use the system to trend patterns to predict when equipment will break down so we can perform preventative maintenance before it actually does."

But first, Auer must create a complete and accurate list of HVAC equipment. Data is currently stored in several different databases that are not complete or accurate. To remedy this, Auer is "auditing" buildings by making sure existing data is accurate while looking for unlisted equipment. When located, Auer provides equipment data via a headset to project partner Maria Aguaristi, who inputs the data to a flat file to be uploaded into Famis. Everything is then double checked by Erik Astrup, Preventative Maintenance Coordinator.

"It is extremely important to us to ensure that all data input to Famis is 100 percent complete and accurate," said Bachant.

The project is ongoing and will be continually updated by individual departments once the initial cataloging is complete. Bachant's goal was to start the project by collecting 1,100 pieces of equipment by the end of September. Auer and Aguaristi, who began work on May 7, have already surpassed that by tagging 1,355 pieces of equipment. Before all is said is done, Bachant hopes to have over 40,000 pieces of equipment in the database.

"Expanding our equipment database and Preventative Maintenance program will allow us to prevent problems that could interfere with SLAC operations before they happen," said Bachant.

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