Record quality factor lowers cost of new particle accelerator

December 1, 2015 by Chris Patrick, Oak Ridge National Laboratory
Record quality factor lowers cost of new particle accelerator
An LCLS-II-type accelerator cavity is inserted into a machine to be treated with nitrogen, a process that increases the cavity's quality factor. Credit: Fermilab

A team at DOE's Fermi National Accelerator Laboratory achieved a record-high quality factor when testing the first fully dressed radio-frequency cavity built for a particle accelerator project at DOE's SLAC National Accelerator Laboratory. The quality factor, Q, exceeded the goal for the Linac Coherent Light Source II project and far surpasses current state-of-the-art standards.

A higher Q means a cavity is more efficient at accelerating particles and loses less energy. It opens up a way for future particle accelerators to operate much more efficiently at a much lower cost.

LCLS-II will produce X-rays to probe a wide variety of materials at the nanoscale. Fermilab is responsible for designing, developing, building and testing about 150 nine-cell superconducting RF cavities for the LCLS-II . This was the first integrated test in which a nine-cell cavity was outfitted with all the components it will wear in the LCLS-II accelerator.

"This record Q is really the sum, the final point, of many years of research," said Anna Grassellino, Fermilab Technical Division scientist who leads cavity testing and processing for LCLS-II.

SLAC physicist Marc Ross, LCLS-II cryogenics systems manager, says he's pleased with the results. "It's definitely a victory," Ross said. "These are some of the highest-quality-factor practical resonators ever built."

Grassellino led the Fermilab effort to apply the breakthrough technology, dubbed nitrogen doping, that helped achieve the record Q of 3.1 x 1010 at 2 Kelvin and at a 16-megavolt-per-meter peak surface electric field. It involves infusing nitrogen into a 's inner niobium surface.

Nitrogen doping and other Fermilab discoveries that led to this Q value, such as the removal of magnetic flux through rapid cooling, will become new standards for achieving highly efficient accelerators worldwide.

Explore further: NSLS-II reaches 25 milliamps of current with new superconducting RF cavity

Related Stories

Unique SLAC technology to power X-ray laser in South Korea

August 10, 2015

Accelerator technology pioneered at the Department of Energy's SLAC National Accelerator Laboratory is on its way to powering X-ray science in South Korea: On Aug. 6, the lab shipped one of its unique radio-frequency amplifiers ...

New magnet at Fermilab achieves high-field milestone

April 6, 2015

Last month, a new superconducting magnet developed and fabricated at Fermilab reached its design field of 11.5 Tesla at a temperature nearly as cold as outer space. It is the first successful twin-aperture accelerator magnet ...

NSLS-II stores 25 milliamps of current

May 1, 2014

(Phys.org) —Early on April 29, 2014, the National Synchrotron Light Source II (NSLS-II) at the U.S. Department of Energy's Brookhaven National Laboratory stored 25 milliamps (mA) of current at 3 billion electron volts using ...

Recommended for you

How community structure affects the resilience of a network

June 22, 2018

Network theory is a method for analyzing the connections between nodes in a system. One of the most compelling aspects of network theory is that discoveries related to one field, such as cellular biology, can be abstracted ...

The pho­to­elec­tric ef­fect in stereo

June 22, 2018

In the photoelectric effect, a photon ejects an electron from a material. Researchers at ETH have now used attosecond laser pulses to measure the time evolution of this effect in molecules. From their results they can deduce ...

Water can be very dead, electrically speaking

June 21, 2018

In a study published in Science this week, the researchers describe the dielectric properties of water that is only a few molecules thick. Such water was previously predicted to exhibit a reduced electric response but it ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.