Monday, March 30, 2015
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Today's New Announcements

Hannah Bloch, Wall Street Journal columnist, talks in One West at 3 p.m. today

Mac OS X security patches to be enabled on March 31

Managing Conflict (a.m. only) on June 10

Indoor soccer

Pilates registration due today

Employee discount at Chipotle today

Book Fair - March 31 and April 1

Fermilab Village Easter Egg Hunt on April 8 - RSVP by April 1

Two-step and Waltz workshops at Kuhn Barn - April 5

2015 FRA scholarship applications accepted until April 1

Wilson Hall southwest stair work: temporary access restriction through April 4

Networking DNS software upgrade - April 7

Nominations for Employee Advisory Group due April 17

2014 FSA deadline is April 30

Interpersonal Communication Skills course - May 20

Fermilab Board Game Guild

Muscle Toning class

Monday Golf League

Changarro restaurant offers Fermilab employee discount


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Superconducting test accelerator achieves first electron beam

Last week the first SRF cavities of Fermilab's superconducting test accelerator propelled their first electrons. Photo: Reidar Hahn

The newest particle accelerators and those of the future will be built with superconducting radio-frequency (SRF) cavities, and institutions around the world are working hard to develop this technology. Fermilab's advanced superconducting test accelerator was built to take advantage of SRF technology accelerator research and development.

On Friday, after more than seven years of planning and building by scientists and engineers, the accelerator has delivered its first beam.

The Fermilab superconducting test accelerator is a linear accelerator (linac) with three main components: a photoinjector that includes an RF gun coupled to an ultraviolet-laser system, several cryomodules and a beamline. Electron bunches are produced when an ultraviolet pulse generated by the laser hits a cathode located on the back plate of the gun. Acceleration continues through two SRF cavities inside the cryomodules. After exiting the cryomodules, the bunches travel down a beamline, where researchers can assess them.

Each meter-long cavity consists of nine cells made from high-purity niobium. In order to become superconductive, the cavities sit in a vessel filled with superfluid liquid helium at temperatures close to absolute zero.

As RF power pulses through these cavities, it creates an oscillating electric field that runs through the cells. If the charged particles meet the oscillating waves at the right phase, they are pushed forward and propelled down the accelerator.

The major advantage of using superconductors is that the lack of electrical resistance allows virtually all the energy passing through to be used for accelerating particle beams, ultimately creating more efficient accelerators.

"It's more bang for the buck," said Elvin Harms, one of the leaders of the commissioning effort.

The superconducting test accelerator's photoinjector gun first produced electrons in June 2013. In the current run, electrons are being shot through one single-cavity cryomodule, with a second, upgraded model to be installed in the next few months. Future plans call for accelerating the electron beam through an eight-cavity cryomodule, CM2, which was the first to reach the specifications of the proposed International Linear Collider (ILC).

Fermilab is one of the few facilities that provides space for advanced accelerator research and development. These experiments will help set the stage for future superconducting accelerators such as SLAC's Linac Coherent Light Source II, of which Fermilab is one of several partner laboratories.

"The linac is similar to other accelerators that exist, but the ability to use this type of setup to carry out accelerator science experiments and train students is unique," said Philippe Piot, a physicist at Fermilab and professor at Northern Illinois University leading one of the first experiments at the test accelerator. A Fermilab team has designed and is beginning to construct the Integrable Optics Test Accelerator ring, a storage ring that will be attached to the superconducting test accelerator in the years to come.

"This cements the fact that Fermilab has been building up the infrastructure for mastering SRF technology," Harms said. "This is the crown jewel of that: saying that we can build the components, put them together, and now we can accelerate a beam."

Diana Kwon
The superconducting test accelerator team celebrates first beam in the operations center at NML. Vladimir Shiltsev, left, is pointing to an image of the beam. Photo: Pavel Juarez, AD

Tip of the Week: Safety

Improving traffic safety at Fermilab

This pickup truck took a hit in a backing accident on the Fermilab site. Photo: Fermilab Security

In February, Fermilab Security responded to 10 vehicle accidents, five of which were a result of improper backing. While there were no injuries reported, the estimated damage amount for these accidents was $21,923. A pedestrian-versus-vehicle backing near miss took place at Wilson Hall in January.

Backing into cars or stationary objects has become the leading traffic violation at Fermilab, resulting in 50 percent of vehicle accidents in the past few months.

Backing collisions are usually caused by inattention, distraction and not looking 360 degrees around the vehicle prior to backing. Driving in reverse requires drivers to continually check at least three mirrors and perhaps even twist and turn to see out of the back window. The biggest hazard for most of us here at Fermilab is getting hurt in a traffic accident.

Immediate traffic safety improvements are needed to prevent vehicle accidents. In the recent past Fermilab has taken the following steps to improve traffic safety:

  • Established that personnel may not drive any motor vehicle on the Fermilab site while using an electronic communication device, including hands-free devices.
  • Included progressive discipline for parking and moving violations as described in FESHM 10160.
  • Set up an online training course titled Traffic Safety Awareness, which is required for all employees and users.
  • Affixed stickers to laboratory vehicles to remind drivers to check 360 degrees around vehicles before backing.

As spring approaches and we are out and about more, we have to be aware of our surroundings while operating any vehicle, and especially when backing, to prevent vehicle accidents.

For further information on traffic safety, please visit the Traffic Safety Subcommittee Web page. You can also get there by going to the ESH&Q home page, scrolling to Safety and Industrial Hygiene or Security, and clicking on Traffic Safety.

J.B. Dawson

Photo of the Day

The picture of warmth

The Main Injector pond thaws. Photo: Steve Krave, TD

New employees - March

The following regular employees started at Fermilab in March:

Angel DeJong, ND; Mohammed Elrafih, DO; Elias Lopez, AD; Kevin Retzke, SCD; KelliAnn Rubrecht, AD; Valery Stanley, WDRS; Dana Strzalka, TD; Kimberly Veugeler, PPD; Hannsjorg Weber, PPD; Joshua Willhite, ND.

Fermilab welcomes them to the laboratory.

In the News

Hubble and Chandra discover dark matter is not as sticky as once thought

From Astronomy Magazine, March 27, 2015

Astronomers using observations from NASA's Hubble Space Telescope and Chandra X-ray Observatory have found that dark matter does not slow down when colliding with each other. This means that it interacts with itself even less than previously thought. Researchers say this finding narrows down the options for what this mysterious substance might be.

Read more