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In this issue:
A Marriage of Hardware and Hard Work
Powerful Antenna Attached to GLAST Satellite
New Purchasing SOW Format Released
Stanford Community Partnership Program

SLAC Today

Thursday - April 24, 2008

The first assembled production girder for the LCLS sits atop the coordinate measuring machine. (Click on image for larger version.)

A Marriage of Hardware and Hard Work

This week, the first undulator support girder assembly for the Linac Coherent Light Source (LCLS) made its way from the Collider Hall, where technicians are piecing them together, to the Magnetic Measurement Facility for final alignment. Each of the 33 girder assemblies comprises a steel girder, movable supports that position the undulator magnets, a quadrupole magnet, a wire beam scanner and the vacuum chamber that carries the beam.

"This is an exciting point in the assembly," said Eric Lundahl, team leader of the measurement group making the adjustments. "The next step is the marriage of an undulator, and then we have our first undulator–girder assembly."

The girders and associated components must be aligned to very tight tolerances for the LCLS to work properly. The vacuum chamber—an aluminum pipe that carries the beam through the undulator magnet—is a mere 6 millimeters thick. The gap in the undulator where it fits, by contrast, is only 6.8 millimeters, a difference amounting to a few tens of thousandths of an inch. However, the straightness of the beam pipe can only vary by tens of micrometers, making the undulator gap tolerance look huge by comparison.

Technicians plan to test-fit undulators to the girders during the tuning phase in the MMF, but the final assembly will take place in the Undulator Hall (UH). Together, the 5,500 pound girder and undulator will rest atop support stands that are currently awaiting installation in the UH tunnel.

The LCLS is a collaboration of laboratories from across the United States. Argonne National Laboratory managed the design and manufacture of the undulator magnets, vacuum chambers, support stands, girders and associated equipment.

Powerful Antenna Attached to GLAST Satellite


General Dynamics technicians, sitting under the GLAST spacecraft, install a high-gain antenna. (Photo courtesy of NASA/ Kim Shiflett.)

The powerful antenna system that will enable NASA's Gamma-ray Large Area Telescope (GLAST) to communicate with stations on Earth has been successfully connected to the spacecraft in the Astrotech payload processing facility near NASA's Kennedy Space Center.

The Ku Band system is used to downlink science and engineering telemetry. The Ku band system includes a Ku antenna, an antenna pointing mechanism that steers the antenna, and two Ku band transmitters. The Ku band (K-under band) is a portion of the electromagnetic spectrum in the microwave range of frequencies that is used to transmit data.

"The Ku Band system on GLAST enables the transmittal of recorded science and engineering data at a high rate to the ground through the Tracking and Data Relay Satellites (TDRS)," said Al Vernacchio, GLAST Deputy Project Manager at NASA's Goddard Space Flight Center, Greenbelt, Md. "It provides the link that enables the transmission of the large quantity of information gathered by the Large Area Telescope (LAT) and GLAST Burst Monitor (GBM) instruments."

Ku band satellites are also used in satellite communications from remote locations back to a television network's studio for editing and broadcasting.

The S-band antennas have already been connected to GLAST. S-band antennas are used for command uplink, that is, to send commands to the GLAST spacecraft from Earth and to gather real-time engineering telemetry.

Currently, the GLAST satellite is being prepared for launch and is in its final stages of preparation, as the Delta II launch vehicle that will carry it spaceward is also being prepared on Launch-pad 17B.

In the drawings of GLAST, this antenna is the little square panel sticking out below the bottom of the spacecraft. Like the solar panels, the Ku band antenna is stowed at launch and will be deployed once GLAST is in orbit.

The installation of the Ku band antenna completes the integration of the Ku system and of the observatory. The only things that remain are the closeout of the thermal blankets, installation of the star tracker shade and fueling of the propulsion system before the observatory goes to the launch pad. GLAST will launch from the Cape Canaveral Air Station in Florida.

GLAST is a powerful space observatory that will explore the most extreme environments in the Universe, where nature harnesses energies far beyond anything possible on Earth. It will search for signs of new laws of physics and what composes the mysterious dark matter, explain how black holes accelerate immense jets of material to nearly light speed, and help crack the mysteries of the stupendously powerful explosions known as gamma-ray bursts. SLAC managed the development of the observatory's main instrument, the LAT, and runs the Instrument Science Operations Center (ISOC), which will process data for the duration of the mission.

NASA's GLAST mission is an astrophysics and particle physics partnership, developed in collaboration with the U.S. Department of Energy, along with important contributions from academic institutions and partners in France, Germany, Italy, Japan, Sweden, and the United States.

New Purchasing SOW Format Released

As a result of SLAC Improvement Initiative recommendations for the Purchasing Department, a new tool is available for the requestors on how to prepare a statement of work (SOW) for their non-construction-related projects. The SOW is the most essential element of every contract as it tells the contractor what is to be accomplished. The preparation and use of a clear, concise, and complete SOW is essential to sound contracting.

The new format is posted on the Purchasing Department's webpage under Non-Construction SOW Template. For construction-related projects, a SSOW Template is also available under "Forms for Staff." More improvement tools will be announced in the near future to enhance the customer service the Purchasing Department provides to the community.

Stanford Community Partnership Program


On Thursday and Friday, May 1 and 2, Stanford will celebrate its second Community Partnership Program. This biennial event is held in alternating years with Community Day, an open house designed to bring our neighbors on campus. As part of the Community Partnership Program, we instead send Stanford people off campus and into the surrounding communities to perform volunteer service.

Our first Community Partnership Day, held in 2006, was a tremendous success. More than 200 volunteers served, and the reaction from organizations was gratifying. That is why, this year, we have expanded the program to two days and are hoping to increase participation.

I invite all members of the Stanford community-students, staff and faculty-to participate by visiting the Community Day website, where you can sign up for projects and find answers to questions. Transportation to the volunteer sites will be provided. Staff members who have their supervisor's approval can receive up to four hours of "release time" for volunteering during regularly scheduled work hours. Some student groups, including the Frosh Council, are organizing efforts as well.

The Office of Public Affairs, which organizes the Community Partnership Program on behalf of the university, is lining up an impressive list of community groups focusing on crucial issues ranging from health care to homelessness to the environment. The list includes such vital area organizations as Abilities United, Acterra, Bayshore Christian Ministries, the Boys and Girls Club of the Peninsula, Breaking Bread Hot Meals Program, Breast Cancer Connections, Canopy, Ecumenical Hunger Program, Friends of Foothills Park, Hidden Villa, Lytton Gardens, Magic, Redwood City School District, Saint Anthony's Padua Dining Room, Saint Elizabeth Seton School, Save the Bay, Sequoia Audubon Society, Shoreline Park at Mountain View, Urban Ministry and the YMCA of the Mid-Peninsula.

To meet its educational and research mission, Stanford must create and sustain meaningful partnerships with the surrounding communities and the people living there. We affect the surrounding communities, and they affect us. The best way to meet area challenges such as traffic, housing, economic development and environmental sustainability is through earnest cooperation. The Community Partnership Program helps us do that, and I hope you will participate.

Thank you in advance. Your efforts are deeply appreciated by Stanford and by those you help.

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