Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Computer-Assisted Accelerator Design


Custom software tool tests virtual model of proposed next-generation accelerator.

Stephen Brooks uses his own custom software tool to fire electron beams into a virtual model of proposed accelerator designs for eRHIC. The goal: Keep the cost down and be sure the beams will circulate in this proposed next-generation machine.

Brookhaven National Laboratory

Accelerator physicist Stephen Brooks explains how multiple electron beams would circulate in the current design for eRHIC, a proposed electron ion-collider Brookhaven hopes to build using existing RHIC infrastructure.

If you walk by room 201 in Building 911 at the U.S. Department of Energy’s Brookhaven National Laboratory, you might think Stephen Brooks is playing a cool new video game. But Brooks is doing important, innovative work. He’s using his own custom designed software to create a 3-D virtual model of the electron accelerator Brookhaven physicists hope to build inside the tunnel currently housing the Relativistic Heavy Ion Collider (RHIC). His mission is to put the virtual pieces together and help test out designs for eRHIC—a proposed machine that would provide unforeseen insight into the inner structure of protons and heavy ions.

“Once the eRHIC layout is in my code, I put beams through it to verify it works,” Brooks said. “But I can also add errors in the alignment of the magnets, beams, and so on to verify it will work in a practical setting.”

By work he means produce extremely focused high-energy electron beams to pierce into the very heart of RHIC’s counter-circulating protons or heavy ions to create precision 3-D images of gluons—the particles that bind quarks within protons and neutrons, thus imparting visible matter with 99 percent of its mass.

This proposed electron-ion collider would open a new window into nuclear matter, ensuring U.S. leadership in the field for the next several decades. And building such a machine by adding an electron accelerator to the existing RHIC complex would be a cost-effective strategy for achieving this goal.

But keeping the cost down and ensuring functionality of the hundreds of different accelerator components takes planning to be sure things go right.

Designing a subatomic particle racetrack

While there are many codes that can track particles through accelerators, the fully 3-D, interactive nature of Brooks’ code, and the ability to incorporate complex accelerators the size of RHIC, makes it unique.

Using a mouse to navigate from a birds-eye view to a close-up, 3-D, edge-on view of the magnets and the beams circulating inside the machine, he explains, “We can use this code to test that the individual accelerator components in the machine are compatible with each other when they are assembled together.” And to be sure those components will fit within the existing RHIC tunnel, the model incorporates a conventional architectural drawing including physical constraints like concrete walls.

Even more innovative, Brooks’ program incorporates an “evolutionary algorithm optimization feature”—essentially an artificial intelligence mode that can vary any aspect of the accelerator and search for the best design to achieve a particular objective by running repeated simulations.

One goal is to track and minimize the amount of synchrotron radiation emitted by the electron beam. That’s energy that spews off tangent to the charged particles’ circular path, like water droplets flying off a wet towel swung around in a circle, gradually depleting the beam’s energy.

“The design tool also determines, for a given layout of magnets and sequence of beam energies, whether each beam will be focused in a stable way and not spread out in size and become unuseable,” Brooks said.

Two rings are better (and cheaper) than six

Testing different designs and parameters, Brooks and other accelerator scientists arrived at a plan that circulates multiple beams of electrons at a range of energies within each of two electron accelerator rings. It incorporates an innovative “non-scaling, fixed field, alternating gradient” (FFAG) accelerator design originally developed by Brookhaven physicist Dejan Trbojevic, who supervises Brooks.

The “alternating gradient”—alternating directions of the magnetic field—keeps the design relatively compact. “Fixed field” means that beams don’t have to be injected periodically and ramped up to reach higher energy. Instead, the beam can be on continuously as it is brought up to “speed.” And because non-scaling FFAG accelerators can be made out of fairly standard accelerator magnets, such a design would achieve high collision rates while controlling costs.

“Trbojevic realized that you can build magnet channels with stronger focusing than normal that can tolerate a large range of beam energies, with the beams of different energy transported side-by-side of each other within the same ring,” Brooks said. “At eRHIC, the beams would spiral through the machine with the external linear accelerator adding energy each turn, and the beam then following the next path farther out but still within the same beam pipe.”

Brooks’ optimization software tool helped the team identify the ideal design: with five electron beams in a low-energy ring, spanning a factor of 5x in energy, and up to 11 electron beams in a high-energy ring, spanning a factor of 2.7x. This design, fitting all these beams within two stacked accelerator rings instead of the six that were called for in an earlier design, represents a significant cost savings.

So, with its results pointing to fewer rings, relatively low-cost magnets, continuous beam, minimized energy loss, and a plan for how to absorb that lost energy, Brooks’ “gaming” with the eRHIC accelerator design seems to be paying off.

This story is available at:

One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. Brookhaven is operated and managed for DOE's Office of Science by Brookhaven Science Associates, a limited-liability company founded by the Research Foundation for the State University of New York on behalf of Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit applied science and technology organization.

Karen McNulty Walsh | newswise
Further information:

Further reports about: Accelerator Brookhaven Design Laboratory eRHIC electron beams ions particles protons

More articles from Physics and Astronomy:

nachricht Prediction: More gas-giants will be found orbiting Sun-like stars
22.02.2017 | Carnegie Institution for Science

nachricht NASA's fermi finds possible dark matter ties in andromeda galaxy
22.02.2017 | NASA/Goddard Space Flight Center

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>



Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

Latest News

Microhotplates for a smart gas sensor

22.02.2017 | Power and Electrical Engineering

Scientists unlock ability to generate new sensory hair cells

22.02.2017 | Life Sciences

Prediction: More gas-giants will be found orbiting Sun-like stars

22.02.2017 | Physics and Astronomy

More VideoLinks >>>