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Posts Tagged ‘Fermilab’

This article appeared in Fermilab Today on July 24, 2015.

Argonne National Laboratory was attracted to the expertise of this Fermilab magnet team. The team recently developed a pre-prototype magnet for Argonne's APS Upgrade Project. Photo: Doug Howard, Fermilab

Argonne National Laboratory was attracted to the expertise of this Fermilab magnet team. The team recently developed a pre-prototype magnet for Argonne’s APS Upgrade Project. Photo: Doug Howard, Fermilab

A magnet two meters long sits in the Experiment Assembly Area of the Advanced Photon Source at Argonne National Laboratory. The magnet, built by Fermilab’s Technical Division, is fire engine red and has on its back a copper coil that doesn’t quite reach from one end to the other. An opening on one end of the magnet’s steel casing gives it the appearance of a rectangular alligator with its mouth slightly ajar.

“It’s a very pretty magnet,” said Argonne’s Glenn Decker, associate project manager for the accelerator. “It’s simple and it’s easy to understand conceptually. It’s been a very big first step in the APS Upgrade.”

The APS is a synchrotron light source that accelerates electrons nearly to the speed of light and then uses magnets to steer them around a circular storage ring the size of a major-league baseball stadium. As the electrons bend, they release energy in the form of synchrotron radiation — light that spans the energy range from visible to x-rays. This radiation can be used for a number of applications, such as microscopy and spectroscopy.

In 2013, the federal Basic Energy Sciences Advisory Committee, which advises the Director of the Department of Energy’s Office of Science, recommended a more ambitious approach to upgrades of U.S. light sources. The APS Upgrade will create a world-leading facility by using new state-of-the-art magnets to tighten the focus of the APS electron beam and dramatically increase the brightness of its X-rays, expanding its experimental capabilities by orders of magnitude.

Instead of the APS’ present magnet configuration, which uses two bending magnets in each of 40 identical sectors, the upgraded ring will deploy seven bending magnets per sector to produce a brighter, highly focused beam.

Because the APS Upgrade requires hundreds of magnets — many of them quite unusual — Argonne called on experts at Fermilab and Brookhaven National Laboratory for assistance in magnet design and development.

Fermilab took on the task of designing, building and testing a pre-prototype for a groundbreaking M1 magnet — the first in the string of bending magnets that makes up the new APS arrangement.

“At Fermilab we have the whole cycle,” said Fermilab’s Vladimir Kashikhin, who is in charge of magnet designs and simulations. “Because of our experience in magnet technology and the people who can simulate and fabricate magnets and make magnetic measurements, we are capable of making any type of accelerator magnet.”

The M1’s magnetic field is strong at one end and tapers off at the other end, reducing the impact of processes that increase the beam size, producing a brighter beam. Because of this change in field, this magnet is different from anything Fermilab had ever built. But by May, Fermilab’s team had completed and tested the magnet and shipped it to Argonne, where it charged triumphantly through a series of tests.

“The magnetic field shape they were asking for was a little bit challenging,” said Dave Harding, the principal investigator leading the project at Fermilab. “Getting the shape of the steel to produce that distribution and magnetic field required some tinkering. But we did it.”

Although this pre-prototype magnet is unlikely to be installed in the complete storage ring, scientists working in this collaboration view the M1 development as an opportunity to learn about technical difficulties, validate their designs and strengthen their skills.

“Getting our hands on some real hardware injected a dose of reality into our process,” Decker said. “We’re going to take the lessons we learned from this M1 magnet and fold them into the next iteration of the magnet. We’re looking forward to a continuing collaboration with Fermilab’s Technical Division on magnetic measurements and refinement of our magnet designs, working toward the next world-leading hard X-ray synchrotron light source.”

Ali Sundermier

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This Fermilab press release came out on July 8, 2015.

Fermilab's Main Injector accelerator, one of the most powerful particle accelerators in the world, has just achieved a world record for high-energy beams for neutrino experiments. Photo: Fermilab

Fermilab’s Main Injector accelerator, one of the most powerful particle accelerators in the world, has just achieved a world record for high-energy beams for neutrino experiments. Photo: Fermilab

A key element in a particle-accelerator-based neutrino experiment is the power of the beam that gives birth to neutrinos: The more particles you can pack into that beam, the better your chance to see neutrinos interact in your detector. Today scientists announced that Fermilab has set a world record for the most powerful high-energy particle beam for neutrino experiments.

Scientists, engineers and technicians at the U.S. Department of Energy’s Fermi National Accelerator Laboratory have achieved for high-energy neutrino experiments a world record: a sustained 521-kilowatt beam generated by the Main Injector particle accelerator. More than 1,000 physicists from around the world will use this high-intensity beam to more closely study neutrinos and fleeting particles called muons, both fundamental building blocks of our universe.

The record beam power surpasses that of the 400-plus-kilowatt beam sent to neutrino experiments from particle accelerators at CERN.

Setting this world record is an initial step for the Fermilab accelerator complex as it will gradually increase beam power over the coming years. The next goal for the laboratory’s two-mile-around Main Injector accelerator — the final and most powerful in Fermilab’s accelerator chain — is to deliver 700-kilowatt beams to the laboratory’s various experiments. Ultimately, Fermilab plans to make additional upgrades to its accelerator complex over the next decade, achieving beam power in excess of 1,000 kilowatts, also referred to as 1 megawatt.

“We have the world’s highest-power beam for neutrinos, and we’re only going up from here,” said Ioanis Kourbanis, head of the Main Injector Department at Fermilab.

Laboratory-made neutrino experiments start by accelerating a beam of particles, typically protons, and then smashing them into a target to create neutrinos. Scientists then use particle detectors to “catch” as many of those neutrinos as possible and record their interactions. Neutrinos rarely engage with matter: Only one out of every trillion emerging from the proton beam will interact in an experiment’s detector. The more particles in that beam, the more opportunities researchers will have to study these rare interactions.

The amped-up particle beam provided by the Main Injector enriches the lab’s neutrino supply, positioning Fermilab to become the primary laboratory for accelerator-based neutrino research. Neutrinos are also made in stars and in the Earth’s core, and they pass through everything — people and planets alike.

“The idea is that if you build a more intense beam, neutrino scientists from around the world will beat a path to your door,” said Fermilab Deputy Director Joe Lykken. “This is exactly what’s happening.”

Fermilab currently operates four neutrino experiments: MicroBooNE, MINERvA, MINOS+ and the laboratory’s largest-to-date neutrino experiment, NOvA, which sends particles from Fermilab’s suburban Chicago location to a far detector 500 miles away in Ash River, Minnesota. The laboratory is working with scientists from around the world on expanding its short-baseline neutrino program and would also serve as host to the proposed flagship Long-Baseline Neutrino Facility and Deep Underground Neutrino Experiment, or DUNE. Scientists aim to address basic questions about the mass and properties of each kind of neutrino as well as the role neutrinos played in the evolution of the universe.

“Reaching this milestone is a fantastic achievement for Fermilab; beam power is everything in our field,” said DUNE co-spokesperson Mark Thomson of the University of Cambridge. “The ability for Fermilab to deliver, yet again, gives the international neutrino community huge confidence in the future U.S.-hosted neutrino program.”

Fermilab is also preparing to operate two experiments for studying muons, short-lived particles that could reveal secrets about the earliest moments of the universe. The increased beam power will also benefit the Fermilab Test Beam Facility, one of the few facilities in the world that provides muons, pions and other particles that researchers can use to test their particle detectors.

Since 2011, Fermilab has made significant upgrades to its accelerators and reconfigured the complex to provide the best possible particle beams for neutrino and muon experiments. With the dedicated work of the Fermilab Accelerator Division, the Main Injector is on track to nearly double its Tevatron-era beam power by 2016.

“Fermilab’s beamline has been a tremendous driver of neutrino science for many years, and the continued improvements to the intensity mean that it will remain a driver for many years to come,” said Indiana University’s Mark Messier, co-spokesperson for the NOvA experiment.

Fermilab is America’s premier national laboratory for particle physics and accelerator research. A U.S. Department of Energy Office of Science laboratory, Fermilab is located near Chicago, Illinois, and operated under contract by the Fermi Research Alliance LLC. Visit Fermilab’s website at www.fnal.gov, and follow us on Twitter at @Fermilab.

The DOE Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

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Getting teachers back on TRAC

Wednesday, July 8th, 2015

This article appeared in Fermilab Today on July 8, 2015.

Kerbie Reader, a high school math teacher, works at the Muon g-2 ring as part of Fermilab's TRAC program. Photo: Ali Sundermier

Kerbie Reader, a high school math teacher, works at the Muon g-2 ring as part of Fermilab’s TRAC program. Photo: Ali Sundermier

Bonnie Weiberg sits down in front of a small monitor in the Proton Assembly Building at Fermilab. Her job is to test the signal strength of the liquid-argon purification monitors for the proposed DUNE experiment. But Weiberg isn’t your average particle physicist. In fact she isn’t a physicist at all: She’s a physics and chemistry teacher at Niles North High School in Skokie, Illinois.

Weiberg is here this summer as part of the Fermilab TRAC program, which is funded by the Particle Physics Division. Harry Cheung, an associate head for the CMS Department who has been head of the TRAC program since 2010, said that this year, seven teachers were selected from a pool of 33 applicants to be matched with a mentor and work on cutting-edge physics.

The TRAC program gives middle school and high school teachers of science, math, computer science and engineering an opportunity to come to Fermilab, work with a scientist or an engineer for eight weeks, and experience what Fermilab research is like.

This summer the teachers, most of whom are from Illinois, are working on projects such as building and testing photodetectors, reconstructing the Muon g-2 ring and controlling high-voltage supplies for the MINERvA neutrino experiment.

“Many of us haven’t done any research since college,” Weiberg said. “It’s nice to come back and be in a research environment to see what’s happening on the cutting edge.”

Kerbie Reader, a high school math teacher at Forest Ridge School of the Sacred Heart in Bellevue, Washington, said that TRAC is the only program she could find in the country that enables teachers to participate in this sort of research. She appreciates the opportunity to remember what it’s like to be a student and to gain experience that will help her relate to her own students.

“We’re seeing the same material year after year. We forget what it’s like to be the person who’s learning,” Reader said. “Instead of saying it’s been 10 or 20 years since I felt that way, I can say, ‘I felt that way last summer. I get that it’s hard, and this is how we’re going to work through it.'”

Weiberg and Reader agreed that the most valuable aspect of this program is being able to gain real-life experiences that they can bring back to their schools and share with their students. Weiberg is even working on a unit about particle physics to incorporate into her curriculum.

“It’ll help us engage our students more,” Weiberg said. “The more real-world things you can bring into your classroom, the better.”

Reader added that the TRAC program gives her a chance to participate in difficult research: to be challenged and learn the value of getting things wrong.

“I want to teach my students not to give up on something because they think it’s hard, to be able to tell them: making a mistake is not the problem,” Reader said. “Everybody that works on all these fantastic things have been making mistakes their entire lives. The day you figure out what your mistakes are, that’s the day you celebrate.”

Ali Sundermier

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This article appeared in Fermilab Today on June 22, 2015.

Steve Gould of the Fermilab Technical Division prepares a cold test of a short quadrupole coil. The coil is of the type that would go into the High-Luminosity LHC. Photo: Reidar Hahn

Steve Gould of the Fermilab Technical Division prepares a cold test of a short quadrupole coil. The coil is of the type that would go into the High-Luminosity LHC. Photo: Reidar Hahn

Last month, a group collaborating across four national laboratories completed the first successful tests of a superconducting coil in preparation for the future high-luminosity upgrade of the Large Hadron Collider, or HL-LHC. These tests indicate that the magnet design may be adequate for its intended use.

Physicists, engineers and technicians of the U.S. LHC Accelerator Research Program (LARP) are working to produce the powerful magnets that will become part of the HL-LHC, scheduled to start up around 2025. The plan for this upgrade is to increase the particle collision rate, or luminosity, by approximately a factor of 10, so expanding the collider’s physics reach by creating 10 times more data.

“The upgrade will help us get closer to new physics. If we see something with the current run, we’ll need more data to get a clear picture. If we don’t find anything, more data may help us to see something new,” said Technical Division’s Giorgio Ambrosio, leader of the LARP magnet effort.

LARP is developing more advanced quadrupole magnets, which are used to focus particle beams. These magnets will have larger beam apertures and the ability to produce higher magnetic fields than those at the current LHC.

The Department of Energy established LARP in 2003 to contribute to LHC commissioning and prepare for upgrades. LARP includes Brookhaven National Laboratory, Fermilab, Lawrence Berkeley National Laboratory and SLAC. Its members began developing the technology for advanced large-aperture quadrupole magnets around 2004.

The superconducting magnets currently in use at the LHC are made from niobium titanium, which has proven to be a very effective material to date. However, they will not be able to support the higher magnetic fields and larger apertures the collider needs to achieve higher luminosities. To push these limits, LARP scientists and engineers turned to a different material, niobium tin.

Niobium tin was discovered before niobium titanium. However, it has not yet been used in accelerators because, unlike niobium titanium, niobium tin is very brittle, making it susceptible to mechanical damage. To be used in high-energy accelerators, these magnets need to withstand large amounts of force, making them difficult to engineer.

LARP worked on this challenge for almost 10 years and went through a number of model magnets before it successfully started the fabrication of coils for 150-millimeter-aperture quadrupoles. Four coils are required for each quadrupole.

LARP and CERN collaborated closely on the design of the coils. After the first coil was built in the United States earlier this year, the LARP team successfully tested it in a magnetic mirror structure. The mirror structure makes possible tests of individual coils under magnetic field conditions similar to those of a quadrupole magnet. At 1.9 Kelvin, the coil exceeded 19 kiloamps, 15 percent above the operating current.

The team also demonstrated that the coil was protected from the stresses and heat generated during a quench, the rapid transition from superconducting to normal state.

“The fact that the very first test of the magnet was successful was based on the experience of many years,” said TD’s Guram Chlachidze, test coordinator for the magnets. “This knowledge and experience is well recognized by the magnet world.”

Over the next few months, LARP members plan to test the completed quadrupole magnet.

“This was a success for both the people building the magnets and the people testing the magnets,” said Fermilab scientist Giorgio Apollinari, head of LARP. “We still have a mountain to climb, but now we know we have all the right equipment at our disposal and that the first step was in the right direction.”

Diana Kwon

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This article appeared in Fermilab Today on May 27, 2015.

The future Dark Energy Spectroscopic Instrument will be mounted on the Mayall 4-meter telescope. It will be used to create a 3-D map of the universe for studies of dark energy. Photo courtesy of NOAO

The future Dark Energy Spectroscopic Instrument will be mounted on the Mayall 4-meter telescope. It will be used to create a 3-D map of the universe for studies of dark energy. Photo courtesy of NOAO

Dark energy makes up about 70 percent of the universe and is causing its accelerating expansion. But what it is or how it works remains a mystery.

The Dark Energy Spectroscopic Instrument (DESI) will study the origins and effects of dark energy by creating the largest 3-D map of the universe to date. It will produce a map of the northern sky that will span 11 billion light-years and measure around 25 million galaxies and quasars, extending back to when the universe was a mere 3 billion years old.

Once construction is complete, DESI will sit atop the Mayall 4-Meter Telescope in Arizona and take data for five years.

DESI will work by collecting light using optical fibers that look through the instrument’s lenses and can be wiggled around to point precisely at galaxies. With 5,000 fibers, it can collect light from 5,000 galaxies at a time. These fibers will pass the galaxy light to a spectrograph, and researchers will use this information to precisely determine each galaxy’s three-dimensional position in the universe.

Lawrence Berkeley National Laboratory is managing the DESI experiment, and Fermilab is making four main contributions: building the instrument’s barrel, packaging and testing charge-coupled devices, or CCDs, developing an online database and building the software that will tell the fibers exactly where to point.

The barrel is a structure that will hold DESI’s six lenses. Once complete, it will be around 2.5 meters tall and a meter wide, about the size of a telephone booth. Fermilab is assembling both the barrel and the structures that will hold it on the telescope.

“It’s a big object that needs to be built very precisely,” said Gaston Gutierrez, a Fermilab scientist managing the barrel construction. “It’s very important to position the lenses very accurately, otherwise the image will be blurred.”

DESI’s spectrograph will use CCDs, sensors that work by converting light collected from distant galaxies into electrons, then to digital values for analysis. Fermilab is responsible for packaging and testing these CCDs before they can be assembled into the spectrograph.

Fermilab is also creating a database that will store information required to operate DESI’s online systems, which direct the position of the telescope, control and read the CCDs, and ensure proper functioning of the spectrograph.

Lastly, Fermilab is developing the software that will convert the known positions of interesting galaxies and quasars to coordinates for the fiber positioning system.

Fermilab completed these same tasks when it built the Dark Energy Camera (DECam), an instrument that currently sits on the Victor Blanco Telescope in Chile, imaging the universe. Many of these scientists and engineers are bringing this expertise to DESI.

“DESI is the next step. DECam is going to precisely measure the sky in 2-D, and getting to the third dimension is a natural progression,” said Fermilab’s Brenna Flaugher, project manager for DECam and one of the leading scientists on DESI.

These four contributions are set to be completed by 2018, and DESI is expected to see first light in 2019.

“This is a great opportunity for students to learn the technology and participate in a nice instrumentation project,” said Juan Estrada, a Fermilab scientist leading the DESI CCD effort.

DESI is funded largely by the Department of Energy with significant contributions from non-U.S. and private funding sources. It is currently undergoing the DOE CD-2 review and approval process.

“We’re really appreciative of the strong technical and scientific support from Fermilab,” said Berkeley Lab’s Michael Levi, DESI project director.

Diana Kwon

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This article appeared in Fermilab Today on May 5, 2015.

Technicians John Cornele, Pat Healey and Skyler Sherwin have been crucial in preparing the LArIAT detector for beam. The liquid-argon-filled detector saw first beam on Thursday. Photo: Jen Raaf

Technicians John Cornele, Pat Healey and Skyler Sherwin have been crucial in preparing the LArIAT detector for beam. The liquid-argon-filled detector saw first beam on Thursday. Photo: Jen Raaf

Fermilab’s Test Beam Facility (FTBF) now runs a second beamline to provide particles for R&D experiments. The MCenter beamline came back to life last year after an eight-year slumber to join the facility’s other beamline, MTest.

On Thursday, April 30, accelerator operators began using the revived beamline to send particles to its first major experiment, Liquid Argon TPC in a Test Beam (LArIAT), which will help advance particle detector technologies for neutrino experiments.

The FTBF provides experiments with different types of particle beams with a range of energies. Its main purpose is the research and development of particle detectors. It is one of only two sites in the world that provides this service with high-energy hadrons, which are particles made of quarks. Since 2005, the FTBF, with its distinctive orange and blue corrugated-steel roof, has staged more than 50 experiments, conducted by scientists from more than 170 institutions in 30 countries.

“We’re very busy and fully subscribed,” said JJ Schmidt, deputy facility manager at FTBF. “The existence of two beams allows us to serve a broader class of experiments.”

Not only does the new beamline allow FTBF to serve a larger number of users, it also provides room for a greater diversity of experiments. While MTest is aimed at experiments with a turnover of about one to four weeks, MCenter caters to more long-term experiments like LArIAT that will last for months, or even years.

Beautiful tracks at first try
LArIAT is a liquid-argon time projection chamber. Charged particles traveling through the sea of liquid argon ionize the argon atoms, and an electric field causes liberated electrons to drift toward the detector readout. Different particles cause different amounts of ionization, allowing researchers to distinguish between particles such as pions, kaons and protons.

This plot shows LArIAT's first tracks: two views of a charged particle interacting inside the LArIAT detector, which is filled with liquid argon.

This plot shows LArIAT’s first tracks: two views of a charged particle interacting inside the LArIAT detector, which is filled with liquid argon.

The first spill of particles delivered to LArIAT led to immediate success. The detector recorded picture-perfect tracks of charged particles.

Like the test beam, LArIAT will act as a research and development vehicle for future projects. Because neutrinos can be studied only through the particles produced when they interact with material inside a particle detector, being able to reliably characterize these other particles is of great importance.

“This is going to be fantastic not only for LArIAT but all the neutrino experiments that will use its results,” said Jen Raaf, co-spokesperson for LArIAT.

LArIAT will run the test beam for 24 hours a day while experimenters take data. The first run will last about three months, after which the detector’s cryogenic system will undergo upgrades to prepare for longer follow-up runs.

“It’s great that we have a facility where a small experiment can take beam over a long term,” said Brian Rebel, a scientist involved in LArIAT.

About 75 people from 22 institutions from the United States, Europe and Japan work on this experiment.

“Most are young postdocs and Ph.D. students that are enthusiastically doing a great job,” said Flavio Cavanna, LArIAT co-spokesperson.

“It’s an exciting combination of many years of work by the Accelerator, Particle Physics, Neutrino and Scientific Computing divisions to have the capability to do research that is important for making this the premier neutrino laboratory in the world,” Schmidt said.

Diana Kwon

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This article appeared in Fermilab Today on May 1, 2015.

Fermilab Director Nigel Lockyer shakes hands with Jefferson Lab Director Hugh Montgomery by a superconducting coil and its development and fabrication team at Fermilab. Six coils have been made and shipped to Jefferson Lab for use in the CLAS12 experiment. Photo: Reidar Hahn

Fermilab Director Nigel Lockyer shakes hands with Jefferson Lab Director Hugh Montgomery by a superconducting coil and its development and fabrication team at Fermilab. Six coils have been made and shipped to Jefferson Lab for use in the CLAS12 experiment. Photo: Reidar Hahn

A group of Fermilab physicists and engineers was faced with a unique challenge when Jefferson Lab asked them to make the superconducting coils for an upgrade to their CEBAF Large Acceptance Spectrometer experiments. These are some of the largest coils Fermilab has ever built.

Despite obstacles, the sixth coil was completed, packed on a truck and sent to Jefferson Lab to become the last piece of the torus magnet in the lab’s CLAS detector. It arrived on Thursday.

The CLAS detector’s upgrade (CLAS12) will allow it to accept electron beams of up to 11 GeV, matching the beam energy of the Virginia laboratory’s CEBAF electron accelerator after five passes. These improvements will allow Jefferson Lab to more accurately study the properties of atomic nuclei.

A major component of the enhanced detector is the torus magnet, which will be made from the six superconducting coils created at Fermilab. Aside from cleaning, insulating and winding the coils, one of the most important parts of the process is vacuum epoxy impregnation. During this step, air and water vapor are removed from the coils and replaced with an epoxy.

This process is particularly difficult when you’re working on magnets as big as the CLAS12 coils, which are 14 feet long and seven feet wide. Fermilab’s Magnet Systems Department fabrication team, the group responsible for making these massive coils, encountered a major obstacle at the end of March 2014 after finishing the first practice coil.

What they found were dry areas within the coil where the epoxy couldn’t penetrate. These were places where the coils weren’t fixed into place, meaning they could move and generate heat and resistance. This can lead to magnet quench, the transition from superconducting to a normal state — a highly undesirable consequence.

The Fermilab group and Jefferson Lab staff collaborated to come up with a solution. By trying new materials, new temperature profiles and adjusting the time that the epoxy was left to sit and be adsorbed, the team was able to prevent the dry areas from forming.

Fred Nobrega, the lead engineer at Fermilab for the CLAS12 coil project, joined the effort last August.

“It was rewarding for me to join the project near its low point, be able to help get through the hurdle and see this completed,” he said.

Production has been steady since December, with Fermilab sending roughly one coil a month to Jefferson Lab. Although the sixth coil will become the last piece of the torus magnet, the project isn’t complete just yet — the ultimate goal is to make eight identical coils, the six for the magnet and two spares.

“We’re succeeding because we have great people and a productive collaboration with Jefferson Lab, who helped us at difficult moments,” said George Velev, head of the Magnet Systems Department. “We worked together on a tough problem and now we see the results.”

Diana Kwon

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This article appeared in symmetry on April 22, 2015.

The world’s largest liquid-argon neutrino detector will help with the search for sterile neutrinos at Fermilab. Photo: INFN

The world’s largest liquid-argon neutrino detector will help with the search for sterile neutrinos at Fermilab. Photo: INFN

Mysterious particles called neutrinos seem to come in three varieties. However, peculiar findings in experiments over the past two decades make scientists wonder if a fourth is lurking just out of sight.

To help solve this mystery, a group of scientists spearheaded by Nobel laureate Carlo Rubbia plans to bring ICARUS, the world’s largest liquid-argon neutrino detector, across the Atlantic Ocean to the United States. The detector is currently being refurbished at CERN, where it is the first beneficiary of a new test facility for neutrino detectors.

Neutrinos are some of the most abundant and yet also most mysterious particles in the universe. They have tiny masses, but no one is sure why—or where those masses come from. They interact so rarely that they can pass through the entire Earth as if it weren’t there. They oscillate from one type to another, so that even if you start out with one kind of neutrino, it might change to another kind by the time you detect it.

Many theories in particle physics predict the existence of a sterile neutrino, which would behave differently from the three known types of neutrino.

“Finding a fourth type of neutrinos would change the whole picture we’re trying to address with current and future experiments,” says Peter Wilson, a scientist at Fermi National Accelerator Laboratory.

The Program Advisory Committee at Fermilab recently endorsed a plan, managed by Wilson, to place a suite of three detectors in a neutrino beam at the laboratory to study neutrinos—and determine whether sterile neutrinos exist.

Over the last 20 years, experiments have seen clues pointing to the possible existence of sterile neutrinos. Their influence may have caused two different types of unexpected neutrino behavior seen at the Liquid Scintillator Neutrino Detector experiment at Los Alamos National Laboratory in New Mexico and the MiniBooNE experiment at Fermilab.

Both experiments saw indications that a surprisingly large number of neutrinos may be morphing from one kind to another a short distance from a neutrino source. The existence of a fourth type of neutrino could encourage this fast transition.

The new three-detector formation at Fermilab could provide the answer to this mystery.

In the suite of experiments, a 260-ton detector called Short Baseline Neutrino Detector will sit closest to the source of the beam, so close that it will be able to detect the neutrinos before they’ve had a chance to change from one type into another. This will give scientists a baseline to compare with results from the other two detectors. SBND is under construction by a team of scientists and engineers from universities in the United Kingdom, the United States and Switzerland, working with several national laboratories in Europe and the US.

The SBND detector will be filled with liquid argon, which gives off flashes of light when other particles pass through it.

“Liquid argon is an extremely exciting technology to make precision measurements with neutrinos,” says University of Manchester physicist Stefan Soldner-Rembold, who leads the UK project building a large section of the detector. “It’s the technology we’ll be using for the next 20 to 30 years of neutrino research.”

Farther from the beam will be the existing 170-ton MicroBooNE detector, which is complete and will begin operation at Fermilab this year. The MicroBooNE detector was designed to find out whether the excess of particles seen by MiniBooNE was caused by a new type of neutrino or a new type of background. Identifying either would have major implications for future neutrino experiments.

Finally, farthest from the beam would be a liquid-argon detector more than four times the size of MicroBooNE. The 760-ton detector was used in the ICARUS experiment, which studied neutrino oscillations at Gran Sasso Laboratory in Italy using a beam of neutrinos produced at CERN from 2010 to 2014.

Its original beam at CERN is not optimized for the next stage of the sterile neutrino search. “The Fermilab beamline is the only game in town for this type of experiment,” says physicist Steve Brice, deputy head of Fermilab’s Neutrino Division.

And the ICARUS detector “is the best detector in the world to detect this kind of particle,” says Alberto Scaramelli, the former technical director of Gran Sasso National Laboratory. “We should use it.”

Rubbia, who initiated construction of ICARUS and leads the ICARUS collaboration, proposed bringing the detector to Fermilab in August 2013. Since then, the ICARUS, MicroBooNE and SBND groups have banded together to create the current proposal. The updated plan received approval from the Fermilab Program Advisory Committee in February.

“The end product was really great because it went through the full scrutiny of three different collaborations,” says MicroBooNE co-leader Sam Zeller. “The detectors all have complementary strengths.”

In December, scientists shipped the ICARUS detector from the Gran Sasso laboratory to CERN, where it is currently undergoing upgrades. The three-detector short-baseline neutrino program at Fermilab is scheduled to begin operation in 2018.

Kathryn Jepsen

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This article appeared in Fermilab Today on April 21, 2015.

Fermilab's Mu2e groundbreaking ceremony took place on Saturday, April 18. From left: Alan Stone (DOE Office of High Energy Physics), Nigel Lockyer (Fermilab director), Jim Siegrist (DOE Office of High Energy Physics director), Ron Ray (Mu2e project manager), Paul Philp (Mu2e federal project director at the Fermi Site Office), Jim Miller (Mu2e co-spokesperson), Doug Glenzinski (Mu2e co-spokesperson), Martha Michels (Fermilab ESH&Q head), Mike Shrader (Middough architecture firm), Julie Whitmore (Mu2e deputy project manager), Jason Whittaker (Whittaker Construction), Tom Lackowski (FESS). Photo: Reidar Hahn

Fermilab’s Mu2e groundbreaking ceremony took place on Saturday, April 18. From left: Alan Stone (DOE Office of High Energy Physics), Nigel Lockyer (Fermilab director), Jim Siegrist (DOE Office of High Energy Physics director), Ron Ray (Mu2e project manager), Paul Philp (Mu2e federal project director at the Fermi Site Office), Jim Miller (Mu2e co-spokesperson), Doug Glenzinski (Mu2e co-spokesperson), Martha Michels (Fermilab ESH&Q head), Mike Shrader (Middough architecture firm), Julie Whitmore (Mu2e deputy project manager), Jason Whittaker (Whittaker Construction), Tom Lackowski (FESS). Photo: Reidar Hahn

This weekend, members of the Mu2e collaboration dug their shovels into the ground of Fermilab’s Muon Campus for the experiment that will search for the direct conversion of a muon into an electron in the hunt for new physics.

For decades, the Standard Model has stood as the best explanation of the subatomic world, describing the properties of the basic building blocks of matter and the forces that govern them. However, challenges remain, including that of unifying gravity with the other fundamental forces or explaining the matter-antimatter asymmetry that allows our universe to exist. Physicists have since developed new models, and detecting the direct conversion of a muon to an electron would provide evidence for many of these alternative theories.

“There’s a real possibility that we’ll see a signal because so many theories beyond the Standard Model naturally allow muon-to-electron conversion,” said Jim Miller, a co-spokesperson for Mu2e. “It’ll also be exciting if we don’t see anything, since it will greatly constrain the parameters of these models.”

Muons and electrons are two different flavors in the charged-lepton family. Muons are 200 times more massive than electrons and decay quickly into lighter particles, while electrons are stable and live forever. Most of the time, a muon decays into an electron and two neutrinos, but physicists have reason to believe that once in a blue moon, muons will convert directly into an electron without releasing any neutrinos. This is physics beyond the Standard Model.

Under the Standard Model, the muon-to-electron direct conversion happens too rarely to ever observe. In more sophisticated models, however, this occurs just frequently enough for an extremely sensitive machine to detect.

The Mu2e detector, when complete, will be the instrument to do this. The 92-foot-long apparatus will have three sections, each with its own superconducting magnet. Its unique S-shape was designed to capture as many slow muons as possible with an aluminum target. The direct conversion of a muon to an electron in an aluminum nucleus would release exactly 105 million electronvolts of energy, which means that if it occurs, the signal in the detector will be unmistakable. Scientists expect Mu2e to be 10,000 times more sensitive than previous attempts to see this process.

Construction will now begin on a new experimental hall for Mu2e. This hall will eventually house the detector and the infrastructure needed to conduct the experiment, such as the cryogenic systems to cool the superconducting magnets and the power systems to keep the machine running.

“What’s nice about the groundbreaking is that it becomes a real thing. It’s a long haul, but we’ll get there eventually, and this is a start,” said Julie Whitmore, deputy project manager for Mu2e.

The detector hall will be complete in late 2016. The experiment, funded mainly by the Department of Energy Office of Science, is expected to begin in 2020 and run for three years until peak sensitivity is reached.

“This is a project that will be moving along for many years. It won’t just be one shot,” said Stefano Miscetti, the leader of the Italian INFN group, Mu2e’s largest international collaborator. “If we observe something, we will want to measure it better. If we don’t, we will want to increase the sensitivity.”

Physicists around the world are working to extend the frontiers of the Standard Model. One hundred seventy-eight people from 31 institutions are coming together for Mu2e to make a significant impact on this venture.

“We’re sensitive to the same new physics that scientists are searching for at the Large Hadron Collider, we just look for it in a complementary way,” said Ron Ray, Mu2e project manager. “Even if the LHC doesn’t see new physics, we could see new physics here.”

Diana Kwon

See a two-minute video on the ceremony

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This Fermilab press release came out on April 13, 2015.

This is the first Dark Energy Survey map to trace the detailed distribution of dark matter across a large area of sky. The color scale represents projected mass density: red and yellow represent regions with more dense matter. The dark matter maps reflect the current picture of mass distribution in the universe where large filaments of matter align with galaxies and clusters of galaxies. Clusters of galaxies are represented by gray dots on the map - bigger dots represent larger clusters. This map covers three percent of the area of sky that DES will eventually document over its five-year mission. Image: Dark Energy Survey

This is the first Dark Energy Survey map to trace the detailed distribution of dark matter across a large area of sky. The color scale represents projected mass density: red and yellow represent regions with more dense matter. The dark matter maps reflect the current picture of mass distribution in the universe where large filaments of matter align with galaxies and clusters of galaxies. Clusters of galaxies are represented by gray dots on the map – bigger dots represent larger clusters. This map covers three percent of the area of sky that DES will eventually document over its five-year mission. Image: Dark Energy Survey

Scientists on the Dark Energy Survey have released the first in a series of dark matter maps of the cosmos. These maps, created with one of the world’s most powerful digital cameras, are the largest contiguous maps created at this level of detail and will improve our understanding of dark matter’s role in the formation of galaxies. Analysis of the clumpiness of the dark matter in the maps will also allow scientists to probe the nature of the mysterious dark energy, believed to be causing the expansion of the universe to speed up.

The new maps were released today at the April meeting of the American Physical Society in Baltimore, Maryland. They were created using data captured by the Dark Energy Camera, a 570-megapixel imaging device that is the primary instrument for the Dark Energy Survey (DES).

Dark matter, the mysterious substance that makes up roughly a quarter of the universe, is invisible to even the most sensitive astronomical instruments because it does not emit or block light. But its effects can be seen by studying a phenomenon called gravitational lensing – the distortion that occurs when the gravitational pull of dark matter bends light around distant galaxies. Understanding the role of dark matter is part of the research program to quantify the role of dark energy, which is the ultimate goal of the survey.

This analysis was led by Vinu Vikram of Argonne National Laboratory (then at the University of Pennsylvania) and Chihway Chang of ETH Zurich. Vikram, Chang and their collaborators at Penn, ETH Zurich, the University of Portsmouth, the University of Manchester and other DES institutions worked for more than a year to carefully validate the lensing maps.

“We measured the barely perceptible distortions in the shapes of about 2 million galaxies to construct these new maps,” Vikram said. “They are a testament not only to the sensitivity of the Dark Energy Camera, but also to the rigorous work by our lensing team to understand its sensitivity so well that we can get exacting results from it.”

The camera was constructed and tested at the U.S. Department of Energy’s Fermi National Accelerator Laboratory and is now mounted on the 4-meter Victor M. Blanco telescope at the National Optical Astronomy Observatory’s Cerro Tololo Inter-American Observatory in Chile. The data were processed at the National Center for Supercomputing Applications at the University of Illinois in Urbana-Champaign.

The dark matter map released today makes use of early DES observations and covers only about three percent of the area of sky DES will document over its five-year mission. The survey has just completed its second year. As scientists expand their search, they will be able to better test current cosmological theories by comparing the amounts of dark and visible matter.

Those theories suggest that, since there is much more dark matter in the universe than visible matter, galaxies will form where large concentrations of dark matter (and hence stronger gravity) are present. So far, the DES analysis backs this up: The maps show large filaments of matter along which visible galaxies and galaxy clusters lie and cosmic voids where very few galaxies reside. Follow-up studies of some of the enormous filaments and voids, and the enormous volume of data, collected throughout the survey will reveal more about this interplay of mass and light.

“Our analysis so far is in line with what the current picture of the universe predicts,” Chang said. “Zooming into the maps, we have measured how dark matter envelops galaxies of different types and how together they evolve over cosmic time. We are eager to use the new data coming in to make much stricter tests of theoretical models.”

View the Dark Energy Survey analysis.

The Dark Energy Survey is a collaboration of more than 300 scientists from 25 institutions in six countries. Its primary instrument, the Dark Energy Camera, is mounted on the 4-meter Blanco telescope at the National Optical Astronomy Observatory’s Cerro Tololo Inter-American Observatory in Chile, and its data is processed at the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign.

Funding for the DES Projects has been provided by the U.S. Department of Energy Office of Science, the U.S. National Science Foundation, the Ministry of Science and Education of Spain, the Science and Technology Facilities Council of the United Kingdom, the Higher Education Funding Council for England, ETH Zurich for Switzerland, the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign, the Kavli Institute of Cosmological Physics at the University of Chicago, Financiadora de Estudos e Projetos, Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro, Conselho Nacional de Desenvolvimento Científico e Tecnológico and the Ministério da Ciência e Tecnologia, the Deutsche Forschungsgemeinschaft and the collaborating institutions in the Dark Energy Survey. The DES participants from Spanish institutions are partially supported by MINECO under grants AYA2012-39559, ESP2013-48274, FPA2013-47986 and Centro de Excelencia Severo Ochoa SEV-2012-0234, some of which include ERDF funds from the European Union.

Fermilab is America’s premier national laboratory for particle physics and accelerator research. A U.S. Department of Energy Office of Science laboratory, Fermilab is located near Chicago, Illinois, and operated under contract by the Fermi Research Alliance, LLC. Visit Fermilab’s website at www.fnal.gov and follow us on Twitter at @Fermilab.

The DOE Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

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