Data scientists face off in LSST machine-learning competition

Data scientists trained computers to pick out useful information from LSST’s hi-res snapshots of the universe.

A rendering of the Large Synoptic Survey Telescope’s dome

A new telescope will take a sequence of hi-res snapshots with the world’s largest digital camera, covering the entire visible night sky every few days—and repeating the process for an entire decade. That presents a big data challenge: What’s the best way to rapidly and automatically identify and categorize all of the stars, galaxies and other objects captured in these images?

To help solve this problem, the scientific collaboration that is working on this Large Synoptic Survey Telescope project launched a competition among data scientists to train computers on how to best perform this task. The Photometric LSST Astronomical Time-Series Classification Challenge, or PLAsTiCC, hosted on the Kaggle.com platform, provided a simulated data set for 3 million objects and tasked participants with identifying which of 15 classifications was the best fit for each object.

Kyle Boone, a UC Berkeley graduate student who has been working on computer algorithms in support of the Nearby Supernova Factory experiment and Supernova Cosmology Project efforts at the US Department of Energy’s Lawrence Berkeley National Laboratory, devoted some of his spare time to the international machine-learning challenge in late 2018 while also working toward his PhD.

“As I worked on job applications, I started playing around with this competition to teach myself more about machine learning,” Boone says. Participants could submit their codes up to five times per day to check their performance on a leaderboard for 1 million objects in the test set. The competition ran from September 28, 2018, to December 17, 2018, and Boone was up against 1383 other competitors on 1093 teams.

“During the last few weeks I worked really hard on it,” devoting all of his evenings and weekends to intense coding, he says.

“My results started to become competitive, and I rushed to implement all of the different ideas that I was coming up with. It was fun, and several teams were neck-and-neck until the end. I learned a lot about how to tune machine-learning algorithms. There are a lot of little ‘knobs’ you can tweak to get that extra 1 percent performance.”

While giving a science talk on the final day of the competition, Boone received a text from his fiancée. “She messaged me and said, ‘Congratulations.’ That was pretty exciting,” he says. He won $12,000 for his first-place finish, and also participated in a second phase of the competition that was more open-ended and is driving toward more applicable solutions in categorizing the objects that LSST will see—the latest round concluded January 15.

Renée Hložek, as assistant professor of astrophysics at the University of Toronto in Canada who led the Kaggle challenge, says, “It is really refreshing to see how combinations of approaches lead to really innovative and novel solutions.

“We have big plans for the next iterations of PLAsTiCC, since there are many ways in which the real LSST data will be even more challenging than our current simulations.”

She notes that PLAsTiCC was created through a collaboration between two science groups working on LSST: the Transient and Variable Stars Collaboration and the Dark Energy Science Collaboration.

Gautham Narayan, a Lasker Data Science Fellow at the Space Telescope Science Institute who is a member of TVS and DESC and served as a host for the LSST Kaggle competition, says that the solutions submitted by PLAsTiCC competitors all had different strengths and weaknesses.

“We’re looking at their submissions to see if we can do even better,” he says. It may be possible to mix and match the different solutions to develop an improved code.

“Machine learning is advancing so fast,” he says. “The numbers are staggering to behold.”

Boone says, “The competition really motivated people to think outside the box and come up with new ideas. There were a lot of very interesting ideas that I don’t think have ever been tried before. I think that combining all of the best models is going to give a huge boost and be very useful for LSST.”

In his work at Berkeley Lab, Boone analyzes data taken from telescopes to understand all of the properties of Type Ia supernovae, and develops new models that can provide accurate distance measurements even for distant supernovae. Type Ia supernovae are used as so-called “standard candles” for measuring distances in the universe based on their luminosity, but these measurements can be affected by the size of the galaxy in which they reside.

Boone says he hopes to apply his programming work for the LSST competition to his work at Berkeley Lab. “It’s very relevant to my own research,” he says, adding that he plans to prepare a scientific paper based on the machine-learning code he wrote for the competition.

Editor's note: A version of this article was originally published by Berkeley Lab.

Success after a three-year sprint

After a rush to start up the first large prototype detector, stellar results show the technology for the Deep Underground Neutrino Experiment is ready to shine.

A figure is silhouetted in the opening of a gold-colored room.

When scientists plan to build a new particle detector, they run simulations to get a picture of what the particle interactions will look like. After constructing and starting up the real thing, they expect a period of tuning, adjusting, fiddling, and fixing to get things running smoothly. They normally don’t expect to turn the detector on and see particle tracks of a quality that exceeds their idealized simulations, especially when it is a prototype detector.

And then there is ProtoDUNE.

“It was fantastic, with neater tracks and less noise from electronics than we expected,” says Flavio Cavanna, a scientist at the US Department of Energy’s Fermilab and the co-coordinator for the first ProtoDUNE detector that came to life this fall. “The entire technology operated as we wanted it to, which is beyond what one can dream.”

The Deep Underground Neutrino Experiment (DUNE) is an international endeavor to unlock the mysteries of particles called neutrinos, which could hold the key to one of the biggest unsolved mysteries in physics: why matter exists in the universe. While the DUNE detector modules ultimately will be 20 times larger, this first prototype detector, ProtoDUNE-SP, is still the largest liquid-argon neutrino detector ever brought to life – and a crucial step in making sure DUNE will work as expected.

For Cavanna and hundreds of others from DUNE institutions in North America, Latin America, Europe, and Asia, these exceptional results are the culmination of three years of hard work and fitful nights. In that short stretch of time, an international team of people had to coalesce; transform a chunk of land into an experimental facility; construct buildings, infrastructure, and an enormous cryogenic container; and design and fabricate the pieces for a house-sized detector that would be assembled inside of that container like a ship in a bottle.

“You build a detector, but never know if it really works until you see the first track,” says Roberto Acciarri, assembly and run coordinator for the detector at CERN, the European Center for Nuclear Research. “You always have that small doubt inside your heart: Is this really going to work?”

A late-night phone call

In December 2015, Cavanna was in Japan for work. One night, he received a call from Fermilab’s director asking if he would like to be a coordinator on a new detector. Only a few things at the time were certain, Cavanna says.

First, the new experiment had been approved by CERN and Fermilab, and CERN agreed that it could live at the Neutrino Platform, a brand-new experimental facility. The detector would use argon, an element found in the air we breathe that becomes a liquid at very cold temperatures. It would serve as one of two test beds (both called ProtoDUNE) for technologies to be used in the Fermilab-hosted Deep Underground Neutrino Experiment.

Small Particles, Big Science: The International LBNF/DUNE Project

Second, while many institutions from around the world had formally signed on to participate in DUNE, a full-fledged scientific community dedicated to ProtoDUNE had yet to be identified and organized – and was essential to building a detector of such huge size and scope.

Finally, there was a looming deadline: The detector ideally would be up and running before the start of the long shutdown of the particle accelerator complex at CERN in fall 2018. This was the only way the team could use CERN’s proton beam to make additional measurements in the detector.

“The schedule was tight,” says Fermilab scientist Gina Rameika, the construction coordinator for ProtoDUNE. “Everyone knew the schedule was almost impossible. We had to get it installed and buttoned up in order to get it filled [with liquid argon] and take beam.”

So they got to work.

Build it bigger

Putting together the world’s biggest liquid-argon detector required smart minds and helping hands. The first step was identifying and convincing scientists and engineers willing to make ProtoDUNE-SP the center of their world for the coming three years, working together as a global team.  

“DUNE is conceived and set up as an international project. It’s planetary,” Cavanna says. People signed on to ProtoDUNE-SP from institutions in North America, Europe, Latin America, and Asia. “ProtoDUNE was a prototype of DUNE technologically, but also from this collaborative structure perspective.”

Of course, ProtoDUNE-SP is not the first liquid-argon detector ever constructed. The technology was pioneered at the large scale for the ICARUS detector, which ran from 2010 to 2013 at the Italian National Institute of Nuclear Physics’ Gran Sasso National Laboratory under the leadership of Nobel laureate Carlo Rubbia. The team could also look to other liquid-argon experiments, such as MicroBooNE and LArIAT at Fermilab.

“We had a solid foundation from previous efforts, but DUNE will take liquid-argon technology to the yet unexplored multi-kiloton scale,” says CERN’s Francesco Pietropaolo, convener of the ProtoDUNE high-voltage consortium. “We knew ProtoDUNE would be essential for us to test new technologies and see how we could scale up to the much larger volume needed for DUNE.”

As groups around the globe made design decisions and mock-ups and eventually started fabricating their individual pieces, construction got under way at CERN, with Marzio Nessi as the head of CERN’s Neutrino Platform. The wooded plot of land was transformed as crews extended a nearby facility and carved out a giant pit where ProtoDUNE-SP and its sister detector would live. CERN’s experts built a beamline that would funnel in the particle beam.

Within the pit, welders got to work on a gigantic red steel frame, the external structure that would house the container with the detector components and the liquid argon needed to capture particle interactions. Researchers adapted algorithms and built up the software and hardware that would capture the electronic signals when a particle from the beam smashed into an argon nucleus in the detector. Things started coming together.

Pieces of ProtoDUNE-SP began flowing in from around the world. Researchers from the Physical Sciences Lab at the University of Wisconsin-Madison sent the first of six crucial components called anode plane assemblies, special panels of wire that record particle interactions. On July 14, 2017, Cavanna sat in front of that very large APA shipping box at CERN and wondered how they would produce, test, and install five more before their stringent deadline just a bit more than a year ahead. The teams went into high gear. Detector parts came faster and faster.

Technicians look up at an APA hanging near the red ProtoDUNE frame

An anode plane assembly (APA) is prepared for installation into ProtoDUNE.

Photo by CERN

“There were rumors that we would never make the schedule and we’d be lucky to put in two APAs,” Rameika says. “We were driven to prove we could deliver all of them, and we did.”

Shipments of APAs from Wisconsin and a group of universities supported by the UK Science and Technology Facilities Council arrived. Teams tested detector components, then slid them through a narrow opening in the steel structure to an inner space where only a few people could work at a time. Fragile photo-sensors were added into the APAs. Electronics came together, cables were strung, and soon the temporary entrance in the side of the container was welded shut.

To complete the final installation, technicians slid into the detector through a one-meter diameter manhole in the roof. CERN’s cryogenic experts filled the detector with 800 metric tons of liquid argon and turned on the purifiers, letting the detector cycle the clear liquid and remove any stray bits of non-argon material. The components within were cut off from any rescue should something go wrong. When the filling was completed almost eight weeks later, ProtoDUNE scientists checked the equipment. CERN’s particle accelerator operators sent streams of protons toward the detector, and researchers turned up the power on the high-voltage system.

“The run started with this critical step that was keeping me up every night for three years,” Cavanna says. “It was the moment of bringing the detector to life, and I didn’t know what to expect.”

Current flowed through the high-voltage system at a whopping 180,000 volts – exactly what it was supposed to do, “like it would be written in a textbook,” Cavanna says. Particle tracks showed up on the display, and soon after, celebratory champagne flowed in the ProtoDUNE control room at CERN. People around the world toasted their victory over video connections.

Non-stop data

When you have limited beam time, every second counts. Particles from the accelerator bombarded the ProtoDUNE detector 24 hours a day, seven days a week, but the deadline for shutting down the beam to prepare for a 2-year-long upgrade to the CERN accelerator complex loomed large.

“You basically set aside your life when there’s beam,” Acciarri says. “You are always thinking and making sure everything is working properly. It’s very stressful.”

After beam and detector tuning, between October 2 and November 12, ProtoDUNE-SP researchers collected more than 4 million gorgeous images of particle interactions. Members from participating institutions took shifts in the control rooms to make sure systems were operating as they should and watched the data roll in.

“This is the first time we have had a live, 3-D event display for a liquid-argon detector,” says Tingjun Yang, co-convener for the data reconstruction and analysis group. Starting with the software used for the data analysis of another neutrino experiment, MicroBooNE, multiple groups collaborated to create a package to convert live data into the right format for quick, 3-D images that researchers on shift could use to monitor the detector.

“We recognized this was a really powerful tool that DUNE will want to use,” Yang says. “We developed it, and the data worked. It was very beautiful.”

Particle tracks recorded by ProtoDUNE

This 3-D display shows a particle event at ProtoDUNE. The video shows the full size of the ProtoDUNE-SP detector (white box) and the direction of the particle beam (yellow arrow). Particles from other sources (such as cosmic rays) can be seen throughout the white box, while the red box highlights the region of interest: in this case, an interaction resulting from the particle beam passing through the detector. Event information, such as the momentum of particles in the beam and time of interaction, are located in the lower left corner. For curious minds that want to play with the interface, a selection of 3-D events from ProtoDUNE-SP are available in an online gallery developed by Chao Zhang of Brookhaven National Laboratory.

Over the course of the run, researchers collected data about all sorts of different particles that might come out of a neutrino interaction in a detector: pions, kaons, photons, electrons, protons, and more. Because ProtoDUNE-SP sits on Earth’s surface, it also sees a high number of cosmic rays that the final DUNE detector won’t see from its mile-deep home at the Sanford Underground Research Facility in South Dakota.

“It makes ProtoDUNE a great stress test for the detector and reconstruction capability,” Yang says. If the software tested at ProtoDUNE can handle the high number of particle interactions, it will be almost overqualified for the more serene environment of DUNE. Fermilab’s accelerator complex will send trillions of neutrinos through 800 miles of earth, but the far detectors will see only a handful every day. However, ProtoDUNE-SP’s robust data handling capabilities are needed to search for rare subatomic phenomena, such as the hypothesized decay of protons. It also ensures that DUNE can handle thousands of neutrino interactions in a few seconds if, say, a star explodes in the Milky Way.

ProtoDUNE-SP also collected particles at the full range of energies DUNE expects to see: from 1 to 7 gigaelectronvolts (GeV). In fact, data-taking went so smoothly at these planned energies that researchers even had extra time to capture lower-energy particles, from 0.3 GeV up to 1 GeV. With precise control over the beam, scientists were able to carefully study how particles interact with the argon atoms – important physics studies in their own right – and test the detector components within.

“The technology is here, and it’s ready for DUNE,” Acciarri says. “We’ll take this opportunity to change a few things, both on the hardware and software side, to make things go even smoother, but I do believe we reached more than what we were expecting or asking for this detector to show.”

Looking ahead

There is plenty still to do, Acciarri notes. DUNE will run for decades, so researchers aim to operate the prototype for as long as possible to monitor how the pieces of the detector fare over time. There also are plans for a series of tests on all the subsystems: things like the light detection system, electronics, and high-voltage system. They plan to test their models of fluid dynamics, seeing how the argon circulates in the detector, and how each subsystem affects the others. Two consortia are already working on improvements for the crucial anode plane assemblies for DUNE. On the software side, researchers will work to improve the stability of the system and the speed at which it captures events. And scientists are working to complete a second ProtoDUNE detector at CERN, known as the dual-phase ProtoDUNE.

DUNE already has around 1,000 members from more than 30 countries and continues to grow. With all the ongoing planning, construction, and testing taking place around the world, the team of DUNE scientists and engineers, it seems, will have a busy and collaborative 2019.

“That was something that was quite important beyond the technological success," Cavanna says. “Technology without the right people is just a piece of material that is dead. We grew a community that will bring DUNE to life.”

APA hanging from a crane as it is moved toward the red ProtoDUNE frame

An APA hangs from a crane in CERN’s Neutrino Platform

Photo by CERN

Editor's note: A version of this article was originally published by Fermilab.

Remastered 1964 films show origins of SLAC

Two videos now available digitally in high fidelity tell the story of Stanford Linear Accelerator Center’s inception and construction.

16 mm master print of “The Worlds Within

A pair of 1964 films detailing the construction of Stanford Linear Accelerator Center, later renamed SLAC National Accelerator Laboratory, were recently remastered and are now available for viewing on YouTube thanks to a partnership between the films’ producer, J. Douglas Allen, and the SLAC Archives, History & Records Office.

The films provide a fascinating look back at the origins of SLAC and the history of particle physics in the United States. At the time of the production, SLAC was the largest civilian basic science project ever undertaken in the United States. The site where it was being built, along Sand Hill Road in Menlo Park, California, was then largely orchards and pasture. Today the region is known as Silicon Valley and considered an unparalleled cradle of innovation.

Filmmaker J. Douglas Allen produced a number of films for Stanford in the 1960s and still lives near campus in Menlo Park. After a friend of his happened upon a low-quality copy of “Fabricating the Linear Accelerator” on YouTube, Allen reached out to SLAC to say he had master copies he could offer. SLAC’s Archives, History & Records Office responded and worked with him to turn his 16 mm film prints to new digital masters in full HD quality.

“The archives office was very excited to digitize this historic 16 mm film footage when Doug offered it to us,” says SLAC archivist Dorothy Leung. “We had various cuts in the archives but not the first answer print” [a term for the version of a film in its original intended format].

Allen certainly didn’t set out to work on films about building particle accelerators. He grew up on a ranch in Texas, and after attending Stanford as an undergraduate he went into the Navy and became a pilot. Aviation became his lifelong passion, but he returned to Stanford for business school, and after completing his MBA was awarded a one-year fellowship to the Nuffield Foundation’s Unit for the History of Ideas in London. The fellowship allowed him to combine his interests in geography, flight and photography and study the British documentary craft amongst leading filmmakers of the time.

When he returned to Stanford, he made a few films for the University Relations Office. A neighbor who worked in public affairs at SLAC, Doug Dupen, approached him about signing on with a project that was planning to make films about the lab. Allen billed hourly for his time and had no real crew; he did all the filming and editing himself. An authorization request letter to the AEC estimated a total budget of about $10,000, an amount that would be roughly $84,000 today.

The script was drafted ahead of production, and correspondence shows that even at that time, the prospect of explaining SLAC’s science to the public was a challenge. A letter from then-assistant to the SLAC director Bill Kirk diplomatically notes, “Some few technical facts are not quite correctly put, and we shall probably have a local argument about several statements that might be felicitously phrased.”

Using an Arriflex 16 mm camera, Allen recorded luminary physicists of the time, like SLAC founding director W. K. H. Panofsky and accelerator pioneer Edward L. Ginzton, as well as each individual stage in the process of fabricating a section of the 2-mile linear accelerator.

“I remember being impressed by the size of the project and the technical detail that went into making it,” Allen recalls.

He would go on to devote most of his career to his interest in aviation, making films for the Hiller Aircraft Company, Evergreen Helicopters, Gates Learjet Corporation and many others, but he still recalls the SLAC project fondly. He became close personal friends with Sigurd Varian, a fellow aviation enthusiast who co-invented the klystron technology that power the linear accelerator with his brother, Russell Varian. Allen still has a lamp made from a piece of the accelerator structure in his living room.

Though the films reflect how much has changed over the past half-century, “Worlds Within” ends with a line that also shows how SLAC’s fundamental pursuits endure. The narrator states, “Knowledge, and the fundamental understanding of nature. Products of the greatest quest in man’s history: to search for truth. To forge new paths into the minute jungle, so small that most of it has not yet been conceived in the minds of man.”

Editor's note: This article is adapted from an article originally published by SLAC National Accelerator Laboratory.

The farmer physicist

A graduate student looks for belonging inside and outside academia.

Jake Pasner

If you want to visit the Pasner family farm, you’ll need a truck with four-wheel drive. You’ll need to traverse 4 miles of bumpy dirt road deep into the countryside of Penn Valley, California. But once you arrive, you’ll be greeted by fields of organic onions and garlic, nestled between rolling grassy hills speckled with oak trees. For physicist Jake Pasner, this will always be home.

“I was born on the top floor of that house,” says Pasner, who grew up fixing tractors and picking figs. Now as a physics graduate student at the University of California, Santa Cruz, he’s building detector components and cultivating complex code for the ATLAS experiment at the Large Hadron Collider at CERN.

Growing up, Pasner didn’t play video games or watch television. Rather, he would play with earthworms and inspect bugs while working in the fields with his family.

For Pasner, working on the family farm was a natural bridge into physics. He marveled at the natural world and would pepper his dad with questions. When his dad no longer had the answers, he did his own research. In middle school, he fixed the alternator on one of their big tractors. It made him curious enough about electricity to explore the topic for his eighth grade science fair.

“My dad knew how to build [the alternator], but he didn’t exactly know why it worked,” he says. “So I got a book from the library about how to generate electricity.”

Eventually, Pasner reached the point where even books didn’t have the answers to his questions. So he decided to investigate them for himself by pursuing a PhD in particle physics.

Pasner knew that earning a PhD would be challenging, but it was actually adjusting to the culture within academia that he found the most difficult. 

For most scientists, getting their PhD coincides with another extremely difficult period in life: the transition from adolescence into adulthood. While Pasner was looking for answers to some of the biggest fundamental question in physics, he also found himself confronted with fundamental questions about his place in the world. Between the highs of snowboarding in the Alps with the CERN ski club and discussing physics analyses with colleagues over Friday night beers, a recalcitrant loneliness set in.

“Moving to Europe broadened my horizons,” he says. “But I missed my family’s traditions and the farming community.”

At the same time, Pasner couldn’t ignore the increasing distance between himself and the people back home. “Many of them are raising families in the same town we grew up in,” he says. “We’ve had such different life experiences and just don’t see the world the same way.”

When Pasner came home to visit his dad, they would return to the familiar routine of long days working on the farm. During this time, Pasner would talk to his dad as he always had. But slowly conversations that started with updates about the onion harvest, what fences needed fixing and how many eggs the chickens were laying evolved into discussions about physics. 

Pasner explained general relativity and the concept of planets warping spacetime by describing marbles deforming the surface of a stretched piece of plastic with their weight. He talked to his dad about the scale of the ATLAS experiment and how this enormous particle detector used many of the same principles as a digital camera. Pasner even explained how that alternator they fixed all those years ago wasn’t all that different from the LHC’s magnets; both use coils of wire to swing electrons in a circle and generate a magnetic field.

Pasner’s dad’s curiosity about CERN and this strange world of particle physics grew. In February 2018, he finally made the long journey across the Atlantic Ocean to see the ATLAS experiment for himself. It was his longest trip away from the farm since his international travels as a young adult in the mid-1970s.

“We were walking around Restaurant 1 on a Friday night, and he saw people from all over the world, speaking all sorts of languages,” Pasner says. “My dad is the kind of person who needs to see something to understand it, and I think visiting CERN and seeing ATLAS made him realize just how big and important this project is. 

“My dad is very emotionally reserved, but I think it humbled him. And I think that it helped me a lot to see him there—this farmer from Penn Valley here with me at CERN. It made me realize how our obsession with understanding the beauty of nature can sometimes make us forget about things which are equally important, like the beauty of family.”

Through his evolving relationship with his dad, Panser was able to gradually build a small bridge between his childhood as a farm kid and his adulthood as a physicist. And it made him realize something: “There are curious people everywhere,” he says. “These principles of science aren’t just for us; they’re for everyone. As physicists, we need to be patient and humble. We need to want to bring people into our world and encourage them so that they can enjoy science too.”

Since his dad’s visit in February, Pasner has moved back to California to finish his PhD at UC Santa Cruz. He’s started working more in outreach through his university.

“People’s lives are better when they can understand and appreciate how the world around them works,” he says, “but not everyone feels like science is for them. How can we bridge this gap and make scientific thinking and principles accessible to more people?”

Pasner says he is looking at ways to make science advocacy a career. But there’s something else he needs to do first:

“After I graduate, I plan to spend a few months rebuilding the deer fence on the farm,” he says. “My dad’s starting to get up there in age and could use a hand.”

Looking to the literature

Fermilab’s Inclusivity Journal Club seeks answers to difficult social questions in science.

An illustration of a group of people having a discussion

In 2013, when physicist Daniel Bowring first started working at the US Department of Energy’s Fermi National Accelerator Laboratory, he attended a meeting of scientists that addressed the question of how to make recruitment more inclusive.

Bowring knew that social scientists study workplace inclusivity and diversity, and a peer-reviewed body of literature already existed that could inform and provide guidance. He suggested that, as Fermilab scientists, the group could study that literature. 

Gradually, he found a critical mass of others interested in the idea. Over several discussions, Bowring says he crystallized his thinking and decided that a good avenue to explore the issues would be a journal club.

As scientists, “it’s within our wheelhouse to read papers about statistics and argue about them,” Bowring says. 

In 2017 Bowring founded Fermilab’s Inclusivity Journal Club. A typical meeting includes physicists and postdoctoral researchers as well as non-science staff; students are also welcome to attend. Members read and discuss reports and peer-reviewed papers that address issues such as sexual harassment, implicit bias and best practices for expanding inclusivity.

“The club affords members of the lab community the opportunity to express concerns and ideas and experiences that may be totally foreign to other people that are in the room,” says Sandra Charles, Fermilab’s talent acquisition, diversity and inclusion manager. “That allows for discourse and raises awareness.”

It also helps people become more conscious of their colleagues’ work environment and the unique barriers they may face there.

Fermilab physicist and journal club member Erica Snider says that as a science laboratory, Fermilab should be an exemplar for using evidence-based research to inform practices.

“Why would we do anything other than look at the literature to try to understand what actually works?” she says. “It seemed quite natural to me as a scientist to want to turn to the research.”

All club members are encouraged to seek out and recommend resources for issues they wish to see addressed by the wider community. Anyone can propose a topic. 

Midhat Farooq, a University of Michigan physics graduate student who works on Fermilab’s Muon g-2 experiment, led the club’s June 2018 discussion of a National Academy of Sciences, Engineering & Medicine report on sexual harassment of women in academia.

“It was a really engaging discussion,” Farooq says. The report’s strength lay in the fact that it provided very specific methods to improve an institution’s climate, she says. “I think that was very appealing to a lot of people.”

The report was one of the best things the club has read so far, says Snider, who has a leadership role in Spectrum, the lab’s LGBTQ+ lab resource group. Snider says she was inspired by that meeting to find a similar resource for the LGBTQ+ community. At her suggestion, the club read a best-practices guide for LGBTQ+ inclusivity in physics and astronomy. 

One of the ways the club hopes to have an impact on the wider Fermilab community is simply by sparking discussions beyond its doors, Farooq says. “It’s a small group of people that meets, but my hope is that they go back to their co-workers and talk about it.” 

Club member Mario Lucero, a diversity and inclusion specialist at Fermilab, agrees. “That’s the part I appreciate most, when dialogue happens,” he says. “I feel like these meetings are a catalyst for more in-depth conversations.”

Starting with the research can make it easier for attendees to broach what can be sensitive topics. But moving from the abstract to the personal—examining one’s own social advantages and the effects of one’s actions—is an essential step toward real change, Snider says. “Many of us in the club and the leadership of the club are privileged people,” she says, “so first we have to be aware of that fact and be able to engage in conversations about it.”  

People from underrepresented groups need allies to work together to pull the arc of the moral universe toward justice, Farooq says. “Underrepresented groups are often already burdened enough and face barriers. If they have to do all of the work to remove those barriers, they often fall further behind.”

The journal club isn’t meant to tackle issues related to diversity and inclusion in the workplace on its own, but rather to be a valuable piece of a larger ecosystem of programs and initiatives, Bowring says. 

He says anyone who wants to start a similar club at their own institution doesn’t need much to get going. “The best resource is the people around you,” he says. “It’s all very punk rock. All you need is more than one person and access to the literature.”

 

Additional journal club reading:

 

‘A beautiful gathering of two worlds’

CERN inspired famous Dutch fashion artist Iris van Herpen to create her Magnetic Motion collection.

A designer dress and a particle detector

On March 10, 2018, the underground cavern that holds CERN’s CMS experiment had some rare visitors: fashion models, posing in dresses that seemed part sculpture, part science fiction. It was a photo shoot for the fantastical Magnetic Motion collection, created by famous Dutch fashion artist Iris van Herpen, inspired by the laboratory’s equally fantastical machinery. 

Back in her atelier in a sun-filled warehouse loft in Amsterdam, Van Herpen, 34, stands tall with long red hair before a crowd of mannequins outfitted in black, white and midnight blue garments that seem constructed of industrial materials. At a table, eight young co-workers—mostly with a design background, van Herpen says—are shaping fabrics into forms that resemble the wings of butterflies. About 30 pairs of scissors of different shapes and sizes hang on the wall. 

Van Herpen, who lives in Amsterdam and Paris, started her own label in 2007 after graduating from the Artez Institute of the Arts in Arnhem, The Netherlands. She creates two womenswear collections a year and regularly participates in exhibitions. Anyone who has seen these exhibitions will be unsurprised to learn she follows new developments in science.

“My interest in CERN goes back a long time,” van Herpen says. “I was fascinated by discoveries like the Higgs particle, and I often checked the website for news. CERN appeared to be a magic place.”

In 2014 Ariane Koek, founding director of CERN's Arts@CERN artist-in-residence program, invited van Herpen to visit the European research center.

At CERN, van Herpen and Philip Beesley, a Canadian architect with whom she often collaborates, voyaged underground to tour the detectors of Large Hadron Collider. “We met with physicists who explained in easy language about the collisions of particles, the transitions between matter and antimatter, and how the magnets and devices are linked together,” she says.

One of those physicists was CMS Technical Coordinator Austin Ball. 

“She was very interested in which countries are involved in CERN, how it is run, the gender balance and also what drove the shape and choice of the color scheme of the experiment,” he says. “She asked many questions about our materials.”

Van Herpen says she was struck by the beauty of the ATLAS and CMS detectors. 

“It appeared to be couture, a stitched tapestry of colored wires, magnets and devices, and all applied by hand. Craftsmanship and the power of human collaboration were incredibly tangible.” 

Eye to eye with the experiments, van Herpen did not instantly have visions of the pieces she would create, she says. The main idea she brought home was that CERN is trying to lure, control and understand the invisible forces of nature via technology and human intellect—a familiar task. 

Letting nature decide

Van Herpen does some science and engineering of her own. When she creates a new collection, she uses technology to develop new techniques and new materials.

It’s a time-consuming, collaborative process, she says. “Sometimes we are not able to realize what we intend to. There is analogy with scientific experiments, as a process of trial and error. Only when the desired materials are ready the actual design process starts.”

Van Herpen says she starts with the idea of a silhouette in her head. Using a mannequin or sometimes a model, she drapes the material with her hands. “You could compare it with molding,” she says. 

The time to drape one piece varies from a few hours to three days. “Every single piece is draped by me,” she says, “because cutting expensive materials that took months to develop is scary.”

For the Magnetic Motion collection, van Herpen and Beesley worked with magnet artist Jólan van der Wiel. They did things like adding metal powder to silicon, then placing magnets above and below to shape it into spiky forms. 

“We had no control over the outcome, which was thrilling,” she says. 

In the end, the collection consists of 25 pieces. Some are made with micro-webs of lace veil. Others contain luminescent crystal forms. In still others, sharp, highly reflective feathers punctuate soft shapes. 

“The shoes, belts, necklaces and clutches were ‘grown’ by using magnetic fields,” van Herpen explains.

Van Herpen has a favorite piece in the Magnetic Motion collection, she says. Opening a book of photos, she points to the ‘crystal dress,’ which appears to be made of ice. 

She had previously experimented with different ways to create the illusion of a liquid dress, frozen mid-splash, via a variety of techniques, including 3-D printing. The idea inspired her 2011 collection, Crystallization. TIME Magazine named her 3-D printed dress design one of the 50 best inventions that year.

She had attempted to 3-D print an especially challenging version of the dress using transparent, organic polymers. The company she contacted said that the design was too fragile; they could not do it.

Her visit to CERN inspired her to try again. “Always push the boundaries,” she says. This time, “it was a special moment when it worked.” 

Living in an immaterial world

In 2018, another dream came true: CERN granted van Herpen the rare permission to do a two-day photo shoot of Magnetic Motion at the laboratory. 

In a moment when the LHC was not in use, one truck loaded with the pieces took off from Amsterdam to Geneva, and another carried the equipment of fashion photographer Nick Knight from London. 

All of this led to the moment van Herpen, Knight and a small group of models gathered in front of the CMS detector along with Ball, who was there to deal with technical and safety concerns. 

"Of course the models had to wear safety helmets,” van Herpen says. “We brought transparent ones.”

Ball said he had never seen anything like it. “Without exception all pieces were very ingenious, spectacular, mostly different from anything I expected—and also very difficult to fabricate.” 

Van Herpen says she is grateful for the unique opportunity.

“It was a beautiful gathering of two worlds,” she says. “I have experienced a tip of the iceberg of CERN and believe that I can get even more out of it. Hopefully I will get the chance to return.”

Dark Energy Survey completes six-year mission

Scientists have only just begun to study the remarkably detailed map they created of a portion of the sky.

Photograph of telescopes under a starry sky

After six years of scanning in depth about a quarter of the southern skies, and cataloguing hundreds of millions of distant galaxies, the Dark Energy Survey will finish taking data tomorrow.

DES is an international collaboration that began mapping a 5000-square-degree area of the sky on August 31, 2013, in a quest to understand the nature of dark energy, the mysterious force that is accelerating the expansion of the universe. Using the Dark Energy Camera, a 520-megapixel digital camera mounted on the Blanco 4-meter telescope at the National Science Foundation’s Cerro Tololo Inter-American Observatory in Chile, scientists on DES took data on a total of 758 nights.

Over those nights, they recorded data from a few hundred million distant galaxies. More than 400 scientists from over 25 institutions around the world have been involved in the project, which is hosted by the US Department of Energy’s Fermi National Accelerator Laboratory. The collaboration has already produced about 200 academic papers, with more to come.

According to DES Director Rich Kron, a Fermilab and University of Chicago scientist, those results and the scientists who made them possible are where much of the real accomplishment of DES lies.

“First generations of students and post-doctoral researchers on DES are now becoming faculty at research institutions and are involved in upcoming sky surveys,” Kron says. “The number of publications and people involved are a true testament to this experiment. Helping to launch so many careers has always been part of the plan, and it’s been very successful.”

DES remains one of the most sensitive and comprehensive surveys of distant galaxies ever performed. The Dark Energy Camera is capable of seeing light from galaxies billions of light-years away, capturing it in unprecedented quality. 

According to Alistair Walker of the National Optical Astronomy Observatory, a DES team member and the Blanco telescope scientist, equipping the telescope with the Dark Energy Camera transformed it into a state-of-the-art survey machine. 

“DECam was needed to carry out DES, but it also created a new tool for discovery, from the Solar System to the distant universe,” Walker says. “For example, 12 new moons of Jupiter were recently discovered with DECam, and the detection of distant star-forming galaxies in the early universe, when the universe was only a few percent of its present age, has yielded new insights into the end of the cosmic dark ages.”

The survey generated 50 terabytes (that’s 50 million megabytes) of data over its six observation seasons. That data is stored and analyzed at the National Center for Supercomputing Applications at the University of Illinois Urbana-Champaign.

“As observations end, NCSA is proud to continue supporting the science productivity of the collaboration by making refined data releases and serving the data well into to 2020s,” says Don Petravick, principal investigator for the Dark Energy Survey data management team at NCSA.

Now the job of analyzing that data takes center stage. DES has already released a full range of papers based on its first year of data, and scientists are now diving into the rich seam of cataloged images from the first several years of data, looking for clues to the nature of dark energy.

The first step in that process, according to Fermilab and University of Chicago scientist Josh Frieman, former director of DES, is to find the signal in all the noise.

“We’re trying to tease out the signal of dark energy against a background of all sorts of non-cosmological stuff that gets imprinted on the data,” Frieman says. “It’s a massive ongoing effort from many different people around the world.” 

The DES collaboration continues to release scientific results from their storehouse of data. Highlights from the previous years include:

DES scientists also spotted the first visible counterpart of gravitational waves ever detected, a collision of two neutron stars that occurred 130 million years ago. DES was one of several sky surveys that detected this gravitational-wave source, opening the door to a new kind of astronomy.

Recently DES issued its first cosmology results based on supernovae (207 of them taken from the first three years of DES data), using a method which 20 years ago provided the first evidence for cosmic acceleration. More comprehensive results on dark energy are expected within the next few years.

The task of amassing such a comprehensive survey was no small feat. Over the course of the survey, hundreds of scientists were called on to work the camera in nightly shifts supported by the staff of the observatory. To organize that effort, DES adopted some of the principles of high-energy physics experiments, in which everyone working on the experiment is involved in its operation in some way.

“This mode of operation also afforded DES an educational opportunity,” says Fermilab scientist Tom Diehl, who managed the DES operations. “Senior DES scientists were paired with inexperienced ones for training, and in time would pass that knowledge on to more junior observers.”

The organizational structure of DES was also designed to give early-career scientists valuable opportunities for advancement, from workshops on writing research proposals to mentors who helped review and edit grant and job applications.

Antonella Palmese, a postdoctoral researcher associate at Fermilab, arrived at Cerro Tololo as a graduate student from University College London in 2015. She quickly came up to speed and returned in 2017 and 2018 as an experienced observer. She also served as a representative for early-career scientists, helping to assist those first making their mark with DES.

“Working with DES has put me in contact with many remarkable scientists from all over the world,” Palmese says. “It’s a special collaboration because you always feel like you are a necessary part of the experiment. There is always something useful you can do for the collaboration and for your own research.”

The Dark Energy Camera will remain mounted on the Blanco telescope at Cerro Tololo for another five to 10 years, and will continue to be a useful instrument for scientific collaborations around the world. Cerro Tololo Inter-American Observatory Director Steve Heathcote says he foresees a bright future for DECam. 

"Although the data-taking for DES is coming to an end, DECam will continue its exploration of the Universe from the Blanco telescope and is expected remain a front-line 'engine of discovery' for many years,” Heathcote says.

The DES collaboration will now focus on generating new results from its six years of data, including new insights into dark energy. With one era at an end, the next era of the Dark Energy Survey is just beginning.

Editor’s note: This article is adapted from an article published by Fermilab.