Berkeley Lab

ATAP News, September 2022

Director’s Corner

Cameron Geddes, ATAP Division Director


This issue of ATAP News brings long-awaited news for BELLA Center: completion of the second beamline for the BELLA Petawatt laser. Our scientists and engineers have persevered through the pandemic to design and complete this major upgrade to our capabilities. Its exciting research portfolio will in particular feature experiments on “staging,” or use of the output of one compact, powerful laser-plasma accelerator as the input to another in the quest for higher electron-beam energy relevant to future particle colliders.

One of the exciting big-picture technology trends of our times is the advent of machine learning and, ultimately, artificial intelligence. This issue takes a look at how ATAP researchers are using ML to achieve unprecedented control over particle beams and laser pulses. Though rooted in specific experiments, their work has the potential for broad improvement in accelerators for both discovery science and practical applications.

The achievements of our researchers have been recognized with multiple honors. Axel Huebl of our Accelerator Modeling Program won the IEEE PAST Award for Doctoral Thesis Research, and along with AMP head Jean-Luc Vay and colleague Remi Lehe, is part of a multinational team named as finalists for the ACM Gordon Bell Prize. Gang Huang and Yilun Xu of our Berkeley Accelerator Controls and Instrumentation (BACI) Program were finalists for the R&D 100 Award for their work on QubiC, an open-source control system for quantum processors.

We offer best wishes to longtime ATAP colleague John Corlett, who came here intending to work on the Advanced Light Source for two years during its construction and commissioning, and now, 30 years on, is retiring. We are grateful for his achievements both in accelerator physics and in guiding large, complex projects to success—a skill that he demonstrated and developed in a succession of ATAP endeavors, and which he ultimately applied as head of the Laboratory’s Project Management Office.

Fortunately the status of the pandemic in California has subsided enough for the Lab to relax its indoor mask requirement for workplaces (as of this writing, they remain mandatory for the lengthier close proximity of the shuttle bus). As we return to a greater degree of in-person work, please continue to monitor your health daily, and if in doubt, contact your supervisor about arrangements to work from home. And please, take this opportunity to see our workplace with fresh eyes and rededicate ourselves to safety.


—Advances in physics, medicine, and security enabled by major expansion to one of the world’s most powerful lasers

BELLA SECOND BEAMLINE POINTS TO NEXT-GENERATION PARTICLE ACCELERATORS

Berkeley Lab news release by Alison Hatt

Two people in white lab coats and laser goggles work on equipment

ATAP Division scientists Marlene Turner and Anthony Gonsalves perform work on the laser table where the PW laser is split into the two beam lines. A two-mirror delay stage is also shown, as is one of the delay stages (two mirrors nearly touching at 90 degrees). This is where the femtosecond-precision overlap between the laser arrival times is established (there is another motorized delay stage closer to the accelerator target). (Credit: Marilyn Sargent, Berkeley Lab)

 

Researchers at Lawrence Berkeley National Laboratory (Berkeley Lab) have completed a major expansion of one of the world’s most powerful laser systems, creating new opportunities in accelerator research for the future of high-energy physics and other fields. The expansion created a second beamline for the petawatt laser at the Berkeley Lab Laser Accelerator (BELLA) Center, enabling the development of next-generation particle accelerators for applications in science, medicine, security, and industry. The second beamline came online this summer and is the culmination of several years of planning, design, and engineering by the BELLA and engineering teams.

“We are happy to see construction completed and are very eager to begin the wide variety of exciting experiments that are enabled by the second beamline,” said Eric Esarey, Director of the BELLA Center.

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Using light to move particles

At the BELLA Center, scientists accelerate charged particles with electric fields generated by a high-powered laser interacting with a plasma, creating what’s known as a laser-plasma accelerator (LPA). The team uses a one-petawatt laser that produces a beam of very short pulses or “bullets” of light, one per second, each of which is about a hundred times more powerful than a typical lightning bolt. When the laser beam passes through plasma (a gas-like soup of charged particles), it sets up a moving wave, and a charged particle placed in that wave is then propelled forward, like a surfer on an ocean wave. This “wakefield” approach can produce rates of acceleration up to one thousand times greater than conventional accelerators, making LPAs a promising candidate for the next generation of smaller, less expensive accelerators.

A powerful tool for accelerator technology development

Two pictures showing laser equipment

(Left) Two deformable mirrors. In addition to arrival time and pulse length control of both beam lines, these mirrors allow for independently shaping the focal spot mode, which is critical for optimized staged acceleration. (Right) In the newly-commissioned second beam line, the laser beam travels through the large white tubes into the laser-plasma accelerator vacuum system. Marlene Turner (foreground) and postdoctoral scholar Alex Picksley check for alignment. (Credit: Marilyn Sargent, Berkeley Lab).

 

The second beamline was designed to be highly tunable, able to produce a wide range of laser-spot sizes, with pulse durations and pulse energies that can be varied independently. The two beamlines are intended to be used in tandem, making the system a powerful and versatile tool for science and accelerator technology development. To create the new beamline, the team split off a portion of the main laser beam and ran it through a series of optics to generate a second beam of short, powerful pulses of light that can create a second wakefield.

In particular, the system was designed to enable the team’s vision of staging multiple LPA modules in order to reach the high electron-beam energies needed for particle colliders, using the wakefield of the second beamline to further accelerate particles coming off the first. Initial experiments to achieve this goal are currently underway. In their longer-term vision, the team proposes stacking additional laser-powered modules, to create accelerators of extremely high energies, enabling the next generation of physics discoveries, at a fraction of the cost and size.

As an example, methods to enhance the energy efficiency of LPAs can also be explored with the dual beamlines. The second beamline laser pulse can be configured to absorb any leftover energy in the first beamline plasma that is unused by the acceleration process and then sent to an energy recovery system. Marlene Turner, a scientist in the BELLA Center, received a prestigious early career award from DOE to work on this concept. “Without the second beamline, my research, which aims to decrease the power consumption and environmental impact of future plasma colliders, would not be possible,” said Turner.

The dual beamlines can be used in other configurations as well. For example, the second beamline can be used to accelerate particles to scatter off those from the first beamline, enabling physicists to probe the exotic physics that arise.

“The precision that these two laser beamlines bring, combining femtosecond timing and micron-scale spatial accuracy, is unprecedented at petawatt-class peak power levels, and will enable experiments on LPA staging as well as other advances in plasma acceleration such as laser tailoring of plasma accelerating structures, laser-based methods of particle injection, high energy photon production by laser scattering, and fundamental studies in high field quantum electrodynamics, ” said Tony Gonsalves, the lead scientist on the BELLA petawatt team. “It’s a big deal.”

The power of team science

Berkeley Lab is known as a powerhouse of team science, and this new BELLA project exemplified this ethos. At any one time, the core team working on this project includes ten to fifteen mechanical engineers, electrical engineers, and research scientists, as well as a rotating cast of other key players, including radiological safety specialists and seismic engineers. This has ensured that the two-laser-beamline upgrade not only creates state of the art science, but is executed in a safe, well-engineered, and durable manner that will enable continued productivity for many years to come.

The team encountered their fair share of challenges due to the COVID-19 pandemic, which temporarily shut their facility down. After it reopened, the team had to work in shifts, using a ticketing system to maintain safe density of workers. Just bringing in a team of French engineers to install a compressor chamber took the better part of a year due to pandemic-related restrictions.

“It’s been a long road to get this going, and a much longer road because of COVID,” said Gonsalves. “If you were to count how many people have touched this project, it’d be a very large number. We’re lucky to have this impressive infrastructure of people at the Lab to make a project like this possible.”

Exotic physics and everyday applications

Particle colliders are discovery tools that scientists use to probe the structure of matter by smashing particles together with enough energy to break them apart, helping us understand what the universe is made of and the forces that hold it together. The ultimate goal of the new beamline is to develop a new accelerator technology that will enable colliders to reach higher energies. These questions go way beyond examining visible matter, which actually makes up a small fraction of the universe. There is 5 times more invisible dark matter in the universe than visible matter, and higher energy accelerators may be able to produce heavy dark matter particles so their properties can be studied.

The national security field is also paying attention to these developments in novel accelerator technology. Current technologies to screen for nuclear materials at ports, for nuclear treaties and other applications, are limited in precision. Laser-based accelerator technology, however, could be used to produce the tunable gamma rays or high energy muons needed to accurately detect nuclear compounds or other materials, and the technology could fit into a small, portable unit.

Basic studies in material science would also benefit greatly from the development of compact sources of short wavelength light, such as X-rays, driven by LPAs. Since the LPA intrinsically produces short electron bunches, on the order of femtoseconds, they are ideal to probe materials on ultrafast time scales.

Another exciting application of laser acceleration is in cancer radiation therapy, where the medical community is finding that shorter doses of stronger radiation do less damage to healthy tissues, known as the “flash effect.” These laser systems could revolutionize radiation therapy.

“I am very excited to see the wide variety of science and applications that are enabled by the BELLA second beamline. These are cross-cutting and can impact a number of programs in the Office of Science, the Department of Defense, the National Institutes of Health, as well as in industry,” said Cameron Geddes, Director of Accelerator Technology and Applied Physics Division of Berkeley Lab.

This work was funded by the Department of Energy (DOE) Office of Science High Energy Physics program.


 

MACHINE LEARNING PAVES THE WAY FOR SMARTER PARTICLE ACCELERATORS

Berkeley Lab news release by Will Ferguson

Staff Scientist Daniele Filippetto working on the High Repetition-Rate Electron Scattering Apparatus. (Credit: Thor Swift/Berkeley Lab)

Staff Scientist Daniele Filippetto working on the High Repetition-Rate Electron Scattering Apparatus. (Credit: Thor Swift/Berkeley Lab)

Scientists have developed a new machine-learning platform that makes the algorithms that control particle beams and lasers smarter than ever before. Their work could help lead to the development of new and improved particle accelerators that will help scientists unlock the secrets of the subatomic world.

Daniele Filippetto and colleagues at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) developed the setup to automatically compensate for real-time changes to accelerator beams and other components, such as magnets. Their machine learning approach is also better than contemporary beam control systems at both understanding why things fail, and then using physics to formulate a response. A paper describing the research was published late last year in Nature Scientific Reports.

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“We are trying to teach physics to a chip, while at the same time providing it with the wisdom and experience of a senior scientist operating the machine,” said Filippetto, a staff scientist at the Accelerator Technology & Applied Physics Division (ATAP) at Berkeley Lab and deputy director of the Berkeley Accelerator Controls and Instrumentation Program (BACI) program.

Their research also has the potential to impact multiple applied fields of particle accelerators, ranging from autonomous operations in industrial and medical settings to increased precision in scientific applications, such as linear colliders and ultrafast free electron lasers.

The novel technique was demonstrated at the High Repetition-Rate Electron Scattering Apparatus (HiRES) accelerator at Berkeley Lab in collaboration with researchers from Los Alamos National Laboratory and UCLA. The main application of the HiRES beamline is performing structural dynamics experiments on novel quantum materials. The instrument has contributed to numerous scientific discoveries such as performing the first-ever ultrafast electron diffraction studies of optical melting of tantalum ditelluride, a material with interesting and potentially useful properties. Now, this novel machine is showing its usefulness to develop new methods for controlling broad classes of accelerators.

Particle accelerators produce and accelerate beams of charged particles, such as electrons, protons, and ions, of atomic and subatomic size. As the machines become more powerful and complex, control and optimization of the particle or laser beam becomes more important to meet the needs of scientific, medical, and industrial applications.

Filippetto and colleagues at the BACI program are leading the global development of machine learning tools. These tools provide a platform to develop smart algorithms that react quickly and precisely to unforeseen perturbances, learn from their mistakes, and adopt the best strategy for reaching or maintaining the target beam setpoint.

The tools they are developing have the added advantage of providing an accurate model of the overall behavior of a particle accelerator system, no matter the complexity. Controllers can use these new and improved capabilities to make more effective real-time decisions.

The present focus of Filippetto’s work is using the power and prediction of machine learning tools to increase the overall stability of particle beams.

“If you can predict the beam properties with an accuracy that surpasses their fluctuations, you can then use the prediction to increase the performance of the accelerator,” he said. “Real time knowledge of key beam parameters would have an enormous impact on the final accuracy of experiments.”

At first, such an approach could seem unlikely to produce accurate results, similar to challenges with stock market behavior prediction, but early results from the group are promising. In fact, the algorithm used, which is based on neural network models, shows a tenfold increase in the precision of predicted beam parameters compared to typical statistical analysis. In related work, a recent Halbach award went to Simon Leemann, staff scientist in the Accelerator Physics Group in ATAP, and collaborators for developing machine learning control methods that improve the performance of the Advanced Light Source by stabilizing the highly relativistic electron beam at the experimental source points by roughly one order of magnitude, an unprecedented level.

Early Career Research Scientist Dan Wang working on the piezo inertia motor controllers to drive piezo mirrors, for laser alignment in the coherent laser combining system. (Credit: Thor Swift/Berkeley Lab)

Early Career Research Scientist Dan Wang working on the piezo inertia motor controllers to drive piezo mirrors, for laser alignment in the coherent laser combining system. (Credit: Thor Swift/Berkeley Lab)

In related research, Dan Wang, a research scientist in the BACI group who began her career at Berkeley Lab three years ago as a post-doctoral researcher, is using machine learning tools to advance the technology of control in complex laser systems. In Wang’s case the ultimate goal is to be able to precisely combine hundreds of ultra-intense laser pulses in one powerful and coherent beam the size of a human hair. In a coherent beam, the phase of each input laser must be controlled within a few degrees of error, which is very challenging. The laser energy can be combined in different ways but in all cases, it is imperative that the coherence of the beam array be stabilized against environmental perturbations such as thermal drift, air fluctuations, or even the movement of the supporting table.

To do this, Wang and her colleagues developed a neural network model that is 10 times faster at correcting for system errors in the combined laser array than other conventional methods. The model they developed is also capable of teaching the system to recognize phase errors and parameter change in the lasers and to autocorrect for perturbations when they occur.

The researchers’ method works in both simulations and experiments in lasers, where unprecedented control performance was achieved. The next step in the research is to implement machine learning models on edge computers such as field programmable gate arrays (FPGAs) for faster response, and also to demonstrate the generalization of this machine-learning based control method in more complex systems where there are far more variables to account for.

“I come from an accelerator background, but during my post-doc, my colleagues really helped me to embrace the power of machine learning,” Wang said. “What I’ve learned is that machine learning is a powerful tool to solve a lot of different problems, but you always have to use your physics to guide in how you use and apply it.”

“To meet the needs of new science, this work exemplifies active feedback and machine learning methods that are crucial enablers for the next generation of accelerator and laser performance to power new photon sources and future particle colliders,” said Cameron Geddes, director of the Accelerator Technology & Applied Physics Division.

This work was supported by DOE Office of Science, Office of Basic Energy Sciences and Office of Science High Energy Physics, and the Laboratory Directed Research & Development program.


 

 

NEWS IN BRIEF

 

Using Gases to Generate a Wave of Plasma

By Agnes H. Baker for Gasworld

Tong Zhou at a beam combining experiment

ATAP Division research scientist Tong Zhou conducting fiber laser combination experiments. (Credit: Marilyn Sargent/Berkeley Lab)

Editor’s Note: We take them for granted as they stand near the lab, safety-chained into their racks, but so much depends upon cylinders of purified and pressurized gases. As part of a special feature on Argon and Big Science, the trade-news magazine Gasworld interviewed researchers at our Berkeley Lab Laser Accelerator Center about their research on laser-plasma accelerators and the special role played by laboratory gases. Reproduced by permission. (See the original version here.)

The Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) recently announced the next phase in the development of laser-plasma particle accelerators (LPAs) is underway. This project represents a new approach to high-power lasers. It combines the pulses from many fast-acting but lower-energy optical fiber lasers, and is designed to energize super-compact accelerators.

Gasworld spoke to Berkeley Lab scientists Jeroen van Tilborg, Tong Zhou, Eric Esarey, and Cameron Geddes, director of Berkeley Lab’s Accelerator Technology and Applied Physics (ATAP) Division, to learn more about the LPA project and the gases used in this technology.

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What makes this project a new approach to high-powered lasers?
Berkeley Lab (BL): Our fiber demonstrations provide a path to combining high peak power and high average laser power, at high efficiency, as is needed for high performance plasma-based accelerators.

LPAs offer an alternative way to accelerate and boost the energies of the particles. Rather than using microwaves, an intense beam of laser light is fired through a gas. This generates a plasma wave that charged particles can ride like a surfer. What gases are used?
BL: A broad range of gases are of interest. We typically use pure helium (He) or pure hydrogen (H2). We have found it advantageous to use a mix of He and nitrogen (N2), as well. Novel injection schemes might open up applications of other gases like krypton and argon.

What are some of the challenges related to gas use in the development of these LPAs?
BL: A gas target is ionized to form the plasma in which the acceleration process happens. The gas target itself requires careful design and flow analysis to deliver the desired density and profile. The biggest issue is not so much gas delivery to the accelerator, but dealing with the gas load in the vacuum chambers – the gas must be removed from all regions except the desired target area to allow the laser to focus properly. This is true especially for continuous-flow to provide gas for >kHz repetition rate systems as will be enabled by fiber lasers, and which will, in the future, will require sophisticated gas capture systems. Control over gas mixture is important as well. For example, 0.5% N2 in He might behave differently as an accelerator when compared to 0.6% N2 in He.

Do LPAs use large volumes of gas?
BL: Currently we are using only a small volume at the level of one bottle every two weeks. However, continuous flow systems will use several orders of magnitude more of gas. They will likely require systems to recapture gas from the jet while preserving the surrounding vacuum, to dissipate kW-class heat loads from the recovered gas, and to recycle it.

What are some of the possible new applications for these more sophisticated LPAs?
BL: We are excited about possible application in areas like higher resolution medical imaging, medical radiation therapy, high-energy-density science, high throughput micro-electronics 3D characterization, advanced manufacturing capabilities, nuclear nonproliferation, and homeland security cargo inspection to name a few. Ultimately these LPAs might even be the basis for a new generation of colliders, orders of magnitude smaller – or higher in energy – than today’s, for high-energy physics. Laser-driven colliders require powerful lasers and a high repetition rate. From a simple wallplug power scaling, this demands a dramatic increase in efficiency of laser-plasma accelerators (from wall plug to the electron beam). Fiber lasers can address this increase in efficiency.



 

 

HONORS AND AWARDS

IEEE PAST Doctoral Thesis Award for Axel Huebl

Axel Huebl at podium giving award talk

Huebl gives his acceptance speech at NAPAC 2022. (Credit: Jason Collin/NAPAC2022)

Axel Huebl, a Research Software Engineer in ATAP’s Accelerator Modeling Program, has been honored with the IEEE PAST Doctoral Student Award.

The award is bestowed by the Particle Accelerator Science and Technology (PAST) committee of the Nuclear and Plasma Sciences Society in the Institute of Electrical and Electronics Engineers. It recognizes significant and innovative technical contributions to the field of particle accelerator science and technology as demonstrated in a student’s doctoral thesis.

He received the award August 11 at the 2022 North American Particle Accelerator Conference.

Huebl was honored “for outstanding contributions to the modeling of laser-ion accelerators by pioneering full-geometry modeling on GPUs that led to first-of-a-kind quantitative predictions matching experimental results, and far reaching community building for establishing open standards in plasma acceleration modeling.”

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He also gave an invited talk, “Next Generation Computational Tools for the Modeling and Design of Particle Accelerators at Exascale,” at the conference.

Sandra Biedron presents plaque to Axel Huebl

Prof. Sandra Biedron, NAPAC2022 Chair, presents plaque to Huebl at awards ceremony. (Credit: Jason Collin/NAPAC2022)

Huebl earned his PhD from Technische Universität Dresden while working at Helmholtz-Zentrum Dresden-Rossendorf. (The thesis for which he was honored, “PIConGPU: Predictive Simulations of Laser-Particle Accelerators with Manycore Hardware,” is available online.) After HZDR, he came to Berkeley Lab as a postdoctoral scholar, joining our career research staff in 2020.

With a background in both the physics and the computer-science aspects of modeling, he researches, oversees, and participates in the development and integration of codes (computer programs) that run on high performance computers to simulate particle accelerators, laser beams, and laser plasmas. You can find the latest open-science particle accelerator modeling software from Huebl and his colleagues on GitHub.


 

 

QubiC Named R&D 100 Finalist

R&D 100 Finalist badge

Final round

QubiC—the customizable, modular, open-source qubit control system used by Berkeley Lab’s Advanced Quantum Testbed (AQT)—was named as as one of the 160 finalists for the 2022 R&D 100 Awards.

Established in 1963, the R&D 100 Awards is the only S&T (science and technology) awards competition that recognizes new commercial products, technologies and materials for their technological significance that are available for sale or license.

The results have since been announced, and although QubiC did not win, “being a finalist is a substantial honor, recognizing the potential of this technology to advance quantum computing,” said ATAP Director Cameron Geddes. Berkeley Lab had 7 winners among 10 finalists this year.

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QubiC is capable of the efficient upload and execution of quantum experiments with minimal overhead, can be customized to accommodate unique needs of users, and has demonstrated fast feedback. AQT scientists have used QubiC to develop and implement automated calibration of two-qubit gates.

QubiC’s lead developers were Gang Huang and Yilun Xu of ATAP's Berkeley Accelerator Controls and Instrumentation (BACI) Program. Their work leverages a key aspect of ATAP's particle accelerator legacy: the need for state-of-the-art instrumentation and control systems to precisely stabilize the particle beams and the sophisticated equipment that produces them. The resulting technology and know-how can benefit many other fields, such as quantum computing.

Gang Huang (l.) and Yilun Xu in front of QuBIC installation

Gang Huang (l.) and Yilun Xu led the QubiC design effort that leverages particle accelerator R&D at Berkeley Lab for quantum computing. (Credit: Christian Jünger/Berkeley Lab.). Click to watch a video of Huang and Xu at work and see the QubiC hardware.

BACI, supported by the General Accelerator R&D program in the DOE Office of High Energy Physics, has a decades-long history of developing precision control and feedback systems for particle accelerator projects. “I am very happy to see that previous investment for accelerator controls now can be further developed and used for qubits controls,” said BACI Program Head Derun Li.

“Particle accelerators are a vital component of Berkeley Lab’s scientific endeavors, so the work with advanced FPGA-based RF control technology and engineering for particle beams helped us streamline the customization for quantum hardware,” added Huang. “AQT researchers and testbed users are able to take advantage of the open source toolbox and gain a deeper understanding of flexible control hardware platforms that are both cost-effective and scalable.”


 

 

This incorporates corrections received from Jean-Luc

Three AMP Staffers On Gordon Bell Award Finalists Team

Head shots of L-R:  Axel Huebl, Jean-Luc Vay, Rémi Lehe

L-R: Axel Huebl, Jean-Luc Vay, Rémi Lehe

Jean-Luc Vay, head of ATAP’s Accelerator Modeling Program, and AMP researchers Remi Lehe and Axel Huebl, are part of an international team selected as one of the six finalists for the Association for Computing Machinery’s 2022 Gordon Bell Prize.

They are being honored for “Pushing the frontier in laser-based electron accelerators design with groundbreaking mesh-refined particle-in-cell simulations on pre-exascale supercomputers.”

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The team created a first-of-kind mesh refined (MR) massively parallel Particle-In-Cell (PIC) code for kinetic plasma simulations optimized on the Frontier (the world’s first exascale computer), Fugaku, Summit, and Perlmuttersupercomputers. Major innovations,
implemented in the WarpX PIC code, include:
(i) a three level parallelization strategy that demonstrated performance portability and scaling on millions of A64FX cores and tens of thousands of AMD and Nvidia GPUs;
(ii) a groundbreaking mesh refinement capability that provides between 1.5x to 4x savings in computing requirements on the science case reported in this paper; and
(iii) an efficient load balancing strategy between multiple MR levels.

The MR PIC code enabled 3D simulations of laser-matter interactions on Frontier, Fugaku, and Summit, which have so far been out of the reach of standard codes. These simulations helped remove a major limitation of compact laser-based electron accelerators, which are promising candidates for next generation high-energy physics experiments and for applications such as ultra-high dose rate FLASH radiotherapy.

Besides their strong partners in the U.S. DOE Exascale Computing Project (ECP), including LBNL’s AMReX team, the AMP team partnered with long-time collaborators from CEA Saclay in France, other collaborators from industry and laboratories in France and Japan. Their selection as finalists recognizes the success of the ECP application on accelerator modeling that the team has led. It was the first ECP application to run at scale on Frontier, establishing a new generation of tools that have broad potential for impact in advancing accelerator science.

Theirs is one of two teams with a Berkeley Lab spokesperson among the six finalists.

The winner is presently being selected; the prize will be awarded in mid-November at the Supercomputing 2022 conference.

The Prize is awarded each year to recognize outstanding achievement in high-performance computing. The purpose of the award is to track the progress over time of parallel computing, with particular emphasis on rewarding innovation in applying high-performance computing to applications in science, engineering, and large-scale data analytics. Prizes may be awarded for peak performance or special achievements in scalability and time-to-solution on important science and engineering problems. Financial support of the $10,000 award is provided by Gordon Bell, a pioneer in high-performance and parallel computing.


 

 

Cameron Geddes Named Kavli Fellow, Speaks at NAS Symposium

Kavli Fellow

ATAP Division Director Cameron Geddes was one of the invited speakers at the 2022 Kavli Frontiers of Science Symposia of the National Academies of Sciences (NAS). His talk, which began the High Intensity Lasers session, was “New States of Matter and Capabilities via Precision, High Intensity Lasers.”

The National Academy of Sciences (NAS) selected 74 of the nation’s brightest young scientists from industry, academia, and government to participate in the 2022 U.S. Kavli Frontiers of Science symposia of the NAS. A committee of NAS members selected the participants from among young researchers who have already made recognized contributions to science. Attendees receive the designation of Kavli Fellow.

The Frontiers of Science symposium series provides a forum for the future leaders in U.S. science to share ideas across disciplines and to build contacts and networks as they advance in their careers. More than 6,000 young scientists have participated since the program’s founding in 1989; to date, 298 participants have been elected to the NAS and 17 have been awarded the Nobel Prize.

This year, the National Academy of Sciences held four Kavli Frontiers of Science symposia. The U.S. symposium, which was held April 8-10 in Irvine, Calif., included sessions on beyond human genomics, covid vaccine development and therapeutic RNA molecules, ethics in solar system exploration, fairness accountability and transparency in data science, high intensity lasers, misinformation, disinformation, polarization and social media, scientists’ mother tongue: how language shapes our ability to communicate the unknown and un-natural hazards: socio-political construction of risk and resilience. A complete program for the 32nd US Symposium may be found here.

 

 

WORKPLACE LIFE

Thanks and Best Wishes in Retirement to John Corlett

John Corlett examines a scientific apparatus called an undulator

Corlett examines the actuating mechanism of an undulator (a magnetic array that makes the electron beam in a free-electron laser emit photons) for LCLS-II. (Credit: Marilyn Sargent/Berkeley Lab)

After 30 years at Berkeley Lab, John Corlett, Laboratory Project Management Officer, is retiring effective August 30. He leaves behind a long and distinguished list of research projects that have made lasting contributions to scientific discovery.

Corlett came to Berkeley Lab in December 1991 after several years at Daresbury Laboratory—an accelerator lab in the UK—and three years in the private sector. His expertise in radiofrequency techniques was a good match for the design and construction of the Advanced Light Source storage ring and commissioning phase of the booster, and his original intent was to stay two years for that purpose.

This intention, in hindsight, stood little chance against the exciting things that were going on in the Accelerator and Fusion Research Division, as ATAP was then known. Corlett worked in the Center for Beam Physics, which had just been organized by Swapan Chattopadhyay, based on the Exploratory Studies Group and chartered as a central resource for the Division where theory and experiment (including a thriving group specializing in beam electrodynamics) could come together to incubate ideas. In CBP, Corlett was part of a cohort of future leaders gathered together at an exciting time for accelerator physics.

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As the ALS was commissioned, PEP-II, the energy-asymmetric B-meson factory at SLAC, was getting underway. Berkeley Lab had principal responsibility for the technically challenging low-energy ring of the B factory. Corlett found himself developing a bunch-by-bunch feedback system at the ALS, then parlaying it into the PEP-II LER. This project was developed in a collaboration with KEKB, a B factory at Tsukuba in Japan, as well as other B-factory proposals, enhancing his familiarity with both RF systems and lengthy flights.

The experience of the ALS and PEP-II led to work on damping rings for the SLAC-led proposal for a Next Linear Collider and, later, its technically rather different successor the International Linear Collider. Neither of those efforts came to fruition (though ILC work continue to this day), but in a running theme of Corlett’s career, every accelerator, realized or not, is a learning experience that informs and improves future designs. One spinoff of these efforts was the development of accelerator technologies that underlie the free-electron laser facilities of today.

Corlett was by then expanding his skillset into technical management, serving for several years as head of the Center for Beam Physics under Bill Barletta and then as Deputy Director of the Division for Steve Gourlay.

John Corlett standing at whiteboard with diagrams of RF cavities

Corlett in 2006, heady times for free electron lasers. (Credit: Roy Kaltschmidt/Berkeley Lab)

A series of Berkeley Lab proposals for FEL facilities—LUX and then the Next-Generation Light Source—did not progress to funded projects, but yet another SLAC collaboration ensued: the Linac Coherent Light Source-II project. Several institutions contributed their expertise to this project, which is nearing completion. Berkeley Lab designed and oversaw the construction of the numerous undulator modules for the soft-X-ray beamline and managed final design and construction of the modules for the hard-X-ray beamline. Expertise in high-performance, ultrafast electron guns as injectors for FELs also resulted in a key contribution to LCLS-II. Corlett also worked with SLAC on superconducting cryomodules. (Accelerator-based facilities are in a constant state of evolution; as he moves into retirement, LCLS-II is preparing for initial operations… and design of a high-energy upgrade to LCLS-II is. beginning, an effort that involves ATAP.)

“One of the great things about working at the Lab is that you really can see the value that it adds to humanity and to society. The things that we do are really important to the world. It’s been extremely rewarding to be able to contribute towards that.”

Over the course of his career at the Lab, John perfected the art of collaboration with other scientific institutions. Combined with his experience of project leadership, as well as the research and user community consensus building that leads to Department of Energy program development, led Corlett to a new phase of his career as a project-management professional. Moving from ATAP to the Laboratory Directorate, he served as deputy to Kem Robinson, head of the Project Management Office, and led the office after Robinson’s retirement.

“It’s been really interesting to be on the other side of a project, to be advising and assessing rather than implementing,” Corlett said. “That’s a whole new perspective— taking the operations view of what the Lab needs to provide for projects to be successful.”

His stewardship of the Project Management Office has further developed and strengthened this critical Lab function. In addition to managing the PMO team, John shepherded and assisted a range of complex and critically important projects. including CMB-S4, ALS-U, ESnet 6, and BioEPIC. For CMB-S4, John served as Interim Project Director during a key initial period for the project. He was a critical part of the effort to develop and hone the Lab’s project management capabilities, including two Project Management Advisory Boards (PMABs), which provided assurance and assistance to major mission-critical science and infrastructure projects. Last year, John and his team hired two deputies: Emil Nassar for Science and Engineering projects and Piper Kujac for Construction and Infrastructure projects.

John Corlett standing at retirement party, holding plaque

Colleagues and friends gathered August 17 at Berkeley Lab to celebrate 30 years of technical and managerial contributions and good fellowship.

“There’s a lot of great stuff happening at the Lab, and that’s been a real highlight of the 30 years I’ve been here,” said Corlett. “So many exciting things happening across such a broad spectrum of science. It’s been a terrific place to work, with a lot of opportunity.”

“One of the great things about working at the Lab,” he added, “is that you really can see the value that it adds to humanity and to society. The things that we do are really important to the world. It’s been extremely rewarding to be able to continue towards that.”

We will miss John professionally and personally, along with his keen insights and deft project management. He has made a tremendous impact at the Lab, setting a new bar for excellence in team science. Please join us in thanking him for his significant contributions to the Lab and wishing him well in his next adventure.

This story incorporates elements of a Project Management Office-focused appreciation of Corlett’s career by Berkeley Lab Director Mike Witherell, Deputy Director for Research and Chief Research Officer Carol Burns, and Deputy Director for Operations Michael Brandt.


 

 

Highlanders: Who Said There Can Be Only One?

Stephanie Chan and Asmita Patel both wearing UC-Riverside apparel

Deep and lasting pride in being UC graduates

The 1986 cinematic, ah, landmark Highlander posited that “there can be only one.” ATAP Deputy Division Director for Operations Asmita Patel and Principal Resource Analyst Stephanie Chan—alumnae of the University of California, Riverside, whose teams are the Highlanders—proved otherwise when they showed up at a Zoom meeting in the same school-pride apparel. Proponents of team science, and wielding spreadsheets rather than broadswords, both survived, rather a sharp contrast to the movie.

 


 

OUTREACH AND EDUCATION

SAGE Camp Returns In-Person

Tour group and escorts under the dome of a building

Ina Reichel (front right) gives tour of Advanced Light Source.

 

Science Accelerating Girls’ Engagement in STEM (SAGE) returned to in-person outreach this year. ATAP Outreach and Education Coordinator Ina Reichel led the tour of the Advanced Light Source—a synchrotron light source and one of Berkeley Lab’s DOE user facilities, where ATAP provides accelerator physics support—and helped organize the job shadowing that is a key part of SAGE Camp.

SAGE is a one-week summer camp for public high school students (age 14-17) hosted by National Laboratory scientists and engineers to share what life is like in STEM (Science, Technology, Engineering, and Mathematics) professions.

The program aims to foster innovation, grow the STEM community, and engage intelligent, creative, and passionate young women and other marginalized genders in the everyday life of scientists and engineers. Throughout the week, students participate in job shadowing, hands-on projects, professional development, and more.

The Berkeley Lab K-12 Program has provided a video recap of this summer’s SAGE Camp.

 

 

 

Do You Have Something for our Social Media Feed?

Screen shots showing rapid retweet by DOE-SC

ATAP postings are often retweeted and amplified very promptly

 

Social media has emerged as a prominent way for ATAP to get the word out. We’re always interested in ideas for our Twitter and LinkedIn feeds (and the possibility of developing them into longer stories for the website and newsletter). Great pictures count—high resolution and, preferably, landscape (horizontal) orientation. Let us know! And join us on LinkedIn and Twitter to always get the latest.


 

 

INCLUSION, DIVERSITY, EQUITY AND ACCOUNTABILITY (IDEA)

IDEA and Berkeley Lab Stewardship Values

Screen shot of top-level Lab stewardship values on a picturesque background of the Lab skyline

Our responsibilities to the values of science, to the people,
and to each other

 

Being part of the national laboratory system and of a great university—and being able to spend our careers in the pursuit of discovery and invention—is a remarkable privilege that brings with it responsibilities to society and to each other.

Berkeley Lab has articulated its values on a new website, stewardship.lbl.gov. Two categories of them—earning trust and showing respect—particularly chime with our strategic IDEA goals of making ATAP a place where everyone feels valued and empowered to reach their potential. We encourage you to explore this site and join the discussions along the way on our IDEA journey!

 
A depiction of ATAP stewardship values related to IDEA

Some of the Lab’s stewardship values are particularly relevant to IDEA.

 

 

 

DOE Debuts Energy Justice Week

DOE Justice Week graphic

Making sure that our new energy system does right by everyone

The Department of Energy’s Office of Economic Impact and Diversity (ED) is leading the way for a just transition to a new energy system, and is sponsoring DOE’s first-ever Justice Week, September 12-16.

During Justice Week, DOE will convene internal and external stakeholders to discuss the work the Department has been doing this past year on issues of equity and justice and understand the path ahead to institutionalize this important work. The events will discuss three large initiatives: the DEIA Executive Order (EO 14035), the Equity Executive Order (EO 13985), and the Justice40 Initiative. There will be activities for DOE employees and contractors every day of the week as well as some external events.

 

 

 

PUBLICATIONS AND PRESENTATIONS

Accelerator Modeling Program

Refereed literature

Sahel Hakimi, Lieselotte Obst-Huebl, Axel Huebl, Kei Nakamura, Stepan S. Bulanov (LBNL); Sven Steinke (formerly LBNL, now Marvel Fusion GmbH); Wim P. Leemans (formerly LBNL, now DESY); Zachary Kober, Tobias M. Ostermayr, Thomas Schenkel, Anthony J. Gonsalves, Jean-Luc Vay, Jeroen van Tilborg, Csaba Toth, Carl B. Schroeder, Eric Esarey, and Cameron G. R. Geddes (LBNL), “Laser-solid interaction studies enabled by the new capabilities of the iP2 BELLA PW beamline”, Physics of Plasmas 29, 083102 (19 August 2022); https://doi.org/10.1063/5.0089331

X. Yang (BNL); G. Penn (LBNL); L.H. Yu, V. Smaluk and T. Shaftan (BNL), “Optimization of echo-enabled harmonic generation toward coherent EUV and soft X-ray free-electron laser at NSLS-II,” Nature Scientific Reports 12 (8 June 2022) 9437, https://doi.org/10.1038/s41598-022-13702-3

Invited talks

A. Huebl, “Next Generation Computational Tools For The Modeling And Design Of Particle Accelerators At Exascale”, invited talk, NAPAC22, August 7-12, 202, Albuquerque, NM, USA.

A. Huebl, “Modelling plasma accelerators with the Warp-X PIC code”, in MS “High Performance Computing in Kinetic Simulations of Plasmas. Part I – HPC Opportunities”, PASC22, Basel, Switzerland, June 27th, 2022.

A. Huebl, “Particle Accelerator Modeling at Exascale”, invited Institute Talk at CASUS, HZDR, Goerlitz, Germany, June 23rd, 2022.

A. Huebl, “Particle Accelerator Modeling at Exascale”, Institute Talk at CSI HPC Seminar Series, Computational Science Initiative Brookhaven National Laboratory, USA, June 2nd, 2022.

A. Huebl, Lightning Talk “Python & Cling”, in “Rapid prototyping for exascale: from idea to performance portable applications using Julia, Python, Numba, Chapel, Flang”, ECP BoF Days, invited BoF/panel, May 12th, 2022, virtual, USA.

F. Poeschel et al., incl. A. Huebl as last author. “openPMD – Open and F.A.I.R. I/O for Particle-Mesh Data at the Exascale’, SIAM-PP 22, virtual, USA.

A. Huebl et al., “WarpX – Preparing AMReX and Applications for Frontier and Aurora”, ECP Annual Meeting, invited BoF, May 2-6 2022, virtual, USA.

Conference Proceedings

A. Huebl, R. Lehe, C.E. Mitchell, J. Qiang, R.D. Ryne, R.T. Sandberg, J.-L. Vay, “Next Generation Computational Tools for the Modeling and Design of Particle Accelerators at Exascale,” invited talk and paper in unrefereed Proceedings of the North American Particle Accelerator Conference, Albuquerque, NM, 7-12 August 2022. (preprint of paper to appear in final form on JACoW) (slides)

A. Ferran Pousa et al., including A. Huebl. “Multitask optimization of laser-plasma accelerators using simulation codes with different fidelities,” submitted to IPAC22, 2022.

W. H. Tan et al., including A. Huebl, “Simulation studies of drive-beam instability in a dielectric wakefield accelerator,” IPAC22, 2022.

Advanced Light Source Accelerator Physics

S.C. Leemann, “Machine Learning-Enhanced MOGA for Ultrahigh-Brightness Lattices”, invited talk at the 3rd Workshop on Low Emittance Lattice Design (LEL 2022), ALBA, Barcelona, Spain, June 26-29, 2022 (slides).

Berkeley Lab Laser Accelerator Center

Refereed literature

C. Clarke (SLAC); E. Esarey, C. Geddes (LBNL); G. Hofstaetter (Cornell University); M.J. Hogan (SLAC); S. Nagaitsev (Fermilab and University of Chicago); M. Palmer (BNL); P. Piot (Northern Illinois University and ANL); J. Power (ANL); C. Schroeder (LBNL); D. Umstadter (University of Nebraska-Lincoln); N. Vafaei-Najafabadi (BNL and Stony Brook University); A. Valishev (Fermilab); L. Willingale (University of Michigan); V. Yakimenko (SLAC), “U.S. advanced and novel accelerator beam test facilities,” J. Instrum. 17, T05009 (6 May 2022), https://doi.org/10.1088/1748-0221/17/05/T05009

A. Gonoskov, T. Blackburn, M. Marklund ((University of Gothenburg); S.S. Bulanov (LBNL), “Charged particle motion and radiation in strong electromagnetic fields”, Rev. Mod. Phys. (in press, 2022).

S. Diederichs; C. Benedetti, A. Huebl, R. Lehe, A. Myers, A.Sinn, J.-L.Vay, W. Zhang (LBNL); M. Thévenet (DESY), “HiPACE++: A portable, 3D quasi-static particle-in-cell code,” Computer Physics Communications 278, 108421 (September 2022), https://doi.org/10.1016/j.cpc.2022.108421

S. Diederichs (LBNL, DESY, and University of Hamburg); C. Benedetti, M. Thevenet, E. Esarey, J. Osterhoff, C.B. Schroeder, “Self-stabilizing positron acceleration in a plasma column,” Phys. Rev. Accel. Beams (accepted, 2022).

Qiang Du, Dan Wang, Tong Zhou, Antonio Gilardi, Mariam Kiran, Bashir Mohammed, Derun Li, and Russell Wilcox, “Experimental beam combining stabilization using machine learning trained while phases drift,” Opt. Express 30, 8 12639-12653 (31 March 2022), https://doi.org/10.1364/OE.450255

Laura D. Geulig (LMU Munich); Lieselotte Obst-Huebl, Kei Nakamura, Jianhui Bin, Qing Ji, Sven Steinke, Antoine Snijders, Jian-Hua Mao, Eleanor Blakely, Anthony J. Gonsalves, Stepan S. Bulanov, Jeroen van Tilborg, Carl B. Schroeder, Cameron G.R. Geddes, Eric Esarey (LBNL); Markus Roth (TU Darmstadt and Focused Energy, Inc.); Thomas Schenkel (LBNL), “Online Charge Measurement for Petawatt Laser-Driven Ion Acceleration,” Rev. Sci. Instrum. (accepted, 2022).

Sahel Hakimi, Lieselotte Obst-Huebl, Axel Huebl, Kei Nakamura, Stepan S. Bulanov, Sven Steinke, Wim Leemans, Zachary Kober, Tobias M. Ostermayr, Thomas Schenkel, Anthony J. Gonsalves, Jean-Luc Vay, Jeroen van Tilborg, Csaba Toth, Carl B. Schroeder, Eric Esarey, Cameron G.R. Geddes, “Laser-solid interaction studies enabled by the new capabilities of the iP2 BELLA PW beamline,” Phys. Plasmas 29, 8, 083102 (19 August 2022), https://doi.org/10.1063/5.0089331

Antoine Jeandet (CEA Saclay and Amplitude Laser Group); Spencer W. Jolly, Antonin Borot (CEA Saclay); Benoît Bussière (Amplitude Laser Group); Paul Dumont (SourceLAB); Julien Gautier (Institut Polytechnique de Paris); Olivier Gobert (CEA Saclay); Jean-Philippe Goddet (Institut Polytechnique de Paris); Anthony Gonsalves (LBNL); Arie Irman (HZDR); Wim P. Leemans (LBNL; now DESY); Rodrigo Lopez-Martens (Institut Polytechnique de Paris); Gabriel Mennerat (CEA Saclay); Kei Nakamura (LBNL); Marie Ouillé (Institut Polytechnique de Paris); Gustave Pariente (CEA Saclay); Moana Pittman (Université Paris-Saclay); Thomas Püschel (HZDR); Fabrice Sanson (Amplitude Laser Group and CEA Saclay); François Sylla (SourceLAB); Cédric Thaury (Institut Polytechnique de Paris); Karl Zeil (HZDR); and Fabien Quéré (corresponding author, CEA Saclay), “Survey of spatio-temporal couplings throughout high-power ultrashort lasers,” Optics Express 30, 3 (18 January 2022), https://doi.org/10.1364/OE.444564

G. White, S. Gessner (SLAC); E. Adli, G. J. Cao, K. Sjobak (University of Oslo); S. Barber, C. Schroeder, D. Terzani, J. van Tilborg, E. Esarey (LBNL); C. Doss, M. Litos (University of Colorado-Boulder); I. Lobach, J. Power (ANL); C A. Lindstrøm (DESY), “Beam delivery and final focus systems for multi-TeV advanced linear colliders,” J. Instrum. 17, P05042 (May 2022), https://doi.org/10.1088/1748-0221/17/05/P05042

Invited talks

S.S. Bulanov, “SF QED effects and plasma based collider for high energy physics studies”, QED Laser Plasmas International Workshop, 26-30 September 2022.

L. Obst-Huebl, J. H. Bin, J.-H. Mao, K. Nakamura, S. S. Bulanov, E. A. Blakely, H. Chang, J. De Chant, A. J. Gonsalves, S. Hakimi, L. He, A. Huebl, C. G. R. Geddes, L. Geulig, Q. Ji, Z. Kober,

T. Ostermayr, T. Schenkel, C. B. Schroeder, B. Simmons, S. Steinke, J. van Tilborg, A. M. Snijders, E. Esarey, “The BELLA PW laser proton beamline: a new platform for ultra-high dose rate radiobiological research,” IAEA 3rd Research Coordination Meeting Ion Beam Induced Spatio-Temporal Structural Evolution of Materials: Accelerators for a New Technology Era, CRP No: F11020, 25-29 April 2022.

C.B. Schroeder, Snowmass Electron Source Workshop (virtual, hosted by ANL), Feb 18, 2022, “Plasma photocathode Injectors”.

C.B. Schroeder, Hong Kong University of Science and Technology (HKUST) IAS Workshop on ‘Key beam physics and technologies issues for colliders’ (virtual participation), January 14, 2022, “Plasma colliders”.

M. Turner, “Snowmass Process,” EuroNNAc Special Topics Workshop (Elba, 2022), Title: Snowmass Process.

Tong Zhou et al., “Combining laser pulses in space, time, and spectrum”, NASA Jet Propulsion Laboratory Seminar, March 2022.


 

 

SAFETY: THE BOTTOM LINE

Scenic photo of the Lab site

Figuratively as well as literally a “city on a hill,” we strive to be above reproach in safety and environmental stewardship

Let’s Return to Good Habits as we Return to the Lab

With community transmission of COVID subsiding to low levels, many of us are enjoying the opportunity to return to in-person work. Let’s be our best selves from a safety standpoint. If you are new to the Lab, you might want to also refer to the resources under the Safety tab of this website.

  • Think-Plan-Do behaviors are a proven winner in safe workplaces. Plan your work. Identify the hazards and ensure that you are properly trained and that controls are in place.
  • Workers Observing Workers is another key piece of the safety picture. Let’s take care of each other. Help your co-workers identify and correct unsafe behavior or conditions.

It All Starts with Getting Here Safely

Speed Limit 15 sign

Sitewide limit

•   The Lab site can be a challenging place to drive, so please watch your speed. For cars and bikes alike, the speed limit is 15 mph — or lower where posted.
•  The Laboratory’s badge requirements are meeting with post-pandemic traffic for the first time. Be patient and watchful at the guard gates (and consider the possibility of tailoring your work hours to avoid peak traffic).
•  The Lab and its vicinity are fortunate to have several construction and infrastructure improvement projects. Watch for any flaggers or lowered speed limits, as well as workers and equipment.

Electrical Safety: Don’t Take—or Be— the Path of Least Resistance

Electrical safety logo

Avoid shocking results

Almost all electrical shocks, as well as “near-hit” incidents such as cutting live wires or leaving an electrical panel open, are preventable. If you are not a Qualified Electrical Worker, do not perform electrical work. If becoming a QEW would help in your job, talk with your supervisor about the requisite training.

For QEWs, determine approach boundaries and control access to the area to prevent exposure of other people to electrical hazards.

To Learn More: Refer to the Berkeley Lab Electrical Safety website.If in doubt about the risks of the work you have in mind and whether a QEW must perform it, consult your division’s Electrical Safety Advocates. In ATAP, the Electrical Safety Advocate is Patricia Thomas, x6098.

COVID: Still a Concern

COVID-19 visualization courtesy CDC

Visit covid.lbl.gov

COVID community levels change over time, and therefore so do the Lab’s protocols. (“We’re nowhere near the endemic stage yet,” said White House coronavirus czar Dr. Ashish Jha in a New Yorker interview recommended by Nature.) Thank you for your commitment to maintaining a healthy and safe work environment at Berkeley Lab, and for your continued resilience. The Lab will update everyone as conditions change.

 

Save the Dates for Safety Week! October 31-November 4

Graphic for Save the Dates

About 0.5% of the work year as an investment in safety

 

ATAP’s successful tradition of Safety Week is scheduled for October 31 through November 4 this year. Since it was too good an idea to keep to ourselves, this year, Brookhaven’s Magnet Division and Fermilab’s High-Luminosity LHC Accelerator Upgrade Program will participate simultaneously, and other Berkeley Lab divisions might join us as well. Formerly Safety Day, the event was changed to an hour or two each day for a week in order to increase flexibility and accommodate hybrid work. Visit our Safety Week web page to learn more.

 

 
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