Explore the Wonders of Science at Fermilab on Sunday, April 6, at 1 p.m.

If you know kids between the ages of 7 and 12, you know how hard it can be to get them excited about science from a textbook. Children need science to come to life before their eyes. They need to be wowed, and to experience physical phenomena with eyes wide and jaws dropped.

That’s the thinking behind the annual Wonders of Science show, which will again pack Ramsey Auditorium at the U.S. Department of Energy’s Fermi National Accelerator Laboratory on Sunday, April 6. The show, organized and performed by award-winning high school teachers, is celebrating its 27th year at the lab. Tickets are $4.50 per person.

“This is one of our most exciting events every year,” said Spencer Pasero, an education program leader at Fermilab. “Everyone has their favorite demonstration, but there’s always something new and exciting to look forward to.”

This year’s theme is temperature and energy, and will feature Weird Science, a group of current and retired high school teachers who have been recognized locally and nationally for their ability to engage young minds. Members of the troupe have appeared on The Late Show with David Letterman, CBS News and Inside Edition.

Weird Science includes Lee Marek of the University of Illinois at Chicago (formerly of Naperville North High School), Karl Craddock of Fremd High School in Palatine, and Bill Grosser of Oak Park and River Forest high schools. Together, they will demonstrate eye-popping chemical and physical science experiments designed to be both fun and educational.

“We hope kids leave with the sense that science can be fun, and not only can they enjoy it as an experience, but they also can do it,” Pasero said.

The Wonders of Science show is intended for ages 7-12, and Scout troops are welcome. Each family will receive a science kit, which they can use to conduct their own experiments at home. Children must be accompanied by an adult. Tickets may be ordered online athttp://ed.fnal.gov/events/wos. For additional information, call 630-840-5588 or email edreg@fnal.gov.

The mission of the Fermilab Education Office is to strengthen primary- and secondary-school education by using Fermilab resources to improve teaching and learning in science, mathematics, engineering and technology. The Education Office serves as a catalyst for improving school curricula and is a resource to schools nationwide.

Fermilab is a Department of Energy national laboratory operated under contract by the Fermi Research Alliance, LLC. The DOE Office of Science is the single largest supporter of basic research in the physical sciences in the nation, and helps ensure U.S. world leadership across a broad range of scientific disciplines.

CHICAGO, USA AND GENEVA, SWITZERLAND — Scientists working on the world’s leading particle collider experiments have joined forces, combined their data and produced the first joint result from Fermilab’s Tevatron and CERN’s Large Hadron Collider (LHC), past and current holders of the record for most powerful particle collider on Earth. Scientists from the four experiments involved—ATLAS, CDF, CMS and DZero—announced their joint findings on the mass of the top quark today at the Rencontres de Moriond international physics conference in Italy.

Together the four experiments pooled their data analysis power to arrive at a new world’s best value for the mass of the top quark of 173.34 plus/minus 0.76 GeV/c².

Experiments at the LHC at the CERN laboratory in Geneva, Switzerland and the Tevatron collider at Fermilab near Chicago in Illinois, USA are the only ones that have ever seen top quarks—the heaviest elementary particles ever observed. The top quark’s huge mass (more than 100 times that of the proton) makes it one of the most important tools in the physicists’ quest to understand the nature of the universe.

The new precise value of the top-quark mass will allow scientists to test further the mathematical framework that describes the quantum connections between the top quark, the Higgs particle and the carrier of the electroweak force, the W boson. Theorists will explore how the new, more precise value will change predictions regarding the stability of the Higgs field and its effects on the evolution of the universe. It will also allow scientists to look for inconsistencies in the Standard Model of particle physics – searching for hints of new physics that will lead to a better understanding of the nature of the universe.

“The combining together of data from CERN and Fermilab to make a precision top quark mass result is a strong indication of its importance to understanding nature,” said Fermilab director Nigel Lockyer. “It’s a great example of the international collaboration in our field.”

A total of more than six thousand scientists from more than 50 countries participate in the four experimental collaborations. The CDF and DZero experiments discovered the top quark in 1995, and the Tevatron produced about 300,000 top quark events during its 25-year lifetime, completed in 2011. Since it started collider physics operations in 2009, the LHC has produced close to 18 million events with top quarks, making it the world’s leading top quark factory.

“Collaborative competition is the name of the game,” said CERN’s Director General Rolf Heuer. “Competition between experimental collaborations and labs spurs us on, but collaboration such as this underpins the global particle physics endeavour and is essential in advancing our knowledge of the universe we live in.”

Each of the four collaborations previously released their individual top-quark mass measurements. Combining them together required close collaboration between the four experiments, understanding in detail each other’s techniques and uncertainties. Each experiment measured the top-quark mass using several different methods by analysing different top quark decay channels, using sophisticated analysis techniques developed and improved over more than 20 years of top quark research beginning at the Tevatron and continuing at the LHC.

The joint measurement has been submitted to the electronic arXiv and is available at: http://arxiv.org/abs/1403.4427

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CERN, the European Organization for Nuclear Research, is the world’s leading laboratory for particle physics. It has its headquarters in Geneva. At present, its member states are Austria, Belgium, Bulgaria, the Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Israel, Italy, the Netherlands, Norway, Poland, Portugal, Slovakia, Spain, Sweden, Switzerland and the United Kingdom. Romania is a candidate for accession. Serbia is an associate member in the pre-stage to membership. India, Japan, the Russian Federation, the United States of America, Turkey, the European Commission and UNESCO have observer status.

Fermilab is America’s national laboratory for particle physics 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 athttp://www.fnal.gov and follow us on Twitter at @FermilabToday.To learn more about the DOE’s Office of Science, visithttp://science.energy.gov.

The ATLAS and CMS experiments are international collaborations of universities and research labs, supported by funding agencies around the world. Information about the experiments, including their collaborating institutions, can be found at http://atlas.ch andhttp://cern.ch/cms.

Funding for the CDF and DZero experiments comes from numerous international funding agencies, including the U.S. Department of Energy’s Office of Science and the U.S. National Science Foundation. View a list of CDF’s collaboration institutions at http://www-cdf.fnal.gov/collaboration/index.html, and DZero’s list at http://www-d0.fnal.gov/ib/Institutions.html.

Scientists on the CDF and DZero experiments at the U.S. Department of Energy’s Fermi National Accelerator Laboratory have announced that they have found the final predicted way of creating a top quark, completing a picture of this particle nearly 20 years in the making.

The two collaborations jointly announced on Friday, Feb. 21, that they had observed one of the rarest methods of producing the elementary particle – creating a single top quark through the weak nuclear force, in what is called the “s-channel.” For this analysis, scientists from the CDF and DZero collaborations sifted through data from more than 500 trillion proton-antiproton collisions produced by the Tevatron from 2001 to 2011. They identified about 40 particle collisions in which the weak nuclear force produced single top quarks in conjunction with single bottom quarks.

Top quarks are the heaviest and among the most puzzling elementary particles. They weigh even more than the Higgs boson – as much as an atom of gold – and only two machines have ever produced them: Fermilab’s Tevatron and the Large Hadron Collider at CERN. There are several ways to produce them, as predicted by the theoretical framework known as the Standard Model, and the most common one was the first one discovered: a collision in which the strong nuclear force creates a pair consisting of a top quark and its antimatter cousin, the anti-top quark.

Collisions that produce a single top quark through the weak nuclear force are rarer, and the process scientists on the Tevatron experiments have just announced is the most challenging of these to detect. This method of producing single top quarks is among the rarest interactions allowed by the laws of physics. The detection of this process was one of the ultimate goals of the Tevatron, which for 25 years was the most powerful particle collider in the world.

“This is an important discovery that provides a valuable addition to the picture of the Standard Model universe,” said James Siegrist, DOE associate director of science for high energy physics. “It completes a portrait of one of the fundamental particles of our universe by showing us one of the rarest ways to create them.”

Searching for single top quarks is like looking for a needle in billions of haystacks. Only one in every 50 billion Tevatron collisions produced a single s-channel top quark, and the CDF and DZero collaborations only selected a small fraction of those to separate them from background, which is why the number of observed occurrences of this particular channel is so small. However, the statistical significance of the CDF and DZero data exceeds that required to claim a discovery.

“Kudos to the CDF and DZero collaborations for their work in discovering this process,” said Saul Gonzalez, program director for the National Science Foundation. “Researchers from around the world, including dozens of universities in the United States, contributed to this important find.”

The CDF and DZero experiments first observed particle collisions that created single top quarks through a different process of the weak nuclear force in 2009. This observation was later confirmed by scientists using the Large Hadron Collider.

Scientists from 27 countries collaborated on the Tevatron CDF and DZero experiments and continue to study the reams of data produced during the collider’s run, using ever more sophisticated techniques and computing methods.

“I’m pleased that the CDF and DZero collaborations have brought their study of the top quark full circle,” said Fermilab Director Nigel Lockyer. “The legacy of the Tevatron is indelible, and this discovery makes the breadth of that research even more remarkable.”

Fermilab is America’s national laboratory for particle physics 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 @FermilabToday.

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.

Scientists on the world’s longest-distance neutrino experiment announced today that they have seen their first neutrinos.

The NOvA experiment consists of two huge particle detectors placed 500 miles apart, and its job is to explore the properties of an intense beam of ghostly particles called neutrinos. Neutrinos are abundant in nature, but they very rarely interact with other matter. Studying them could yield crucial information about the early moments of the universe.

“NOvA represents a new generation of neutrino experiments,” said Fermilab Director Nigel Lockyer. “We are proud to reach this important milestone on our way to learning more about these fundamental particles.”

Scientists generate a beam of the particles for the NOvA experiment using one of the world’s largest accelerators, located at the Department of Energy’s Fermi National Accelerator Laboratory near Chicago. They aim this beam in the direction of the two particle detectors, one near the source at Fermilab and the other in Ash River, Minn., near the Canadian border. The detector in Ash River is operated by the University of Minnesota under a cooperative agreement with the Department of Energy’s Office of Science.

Billions of those particles are sent through the earth every two seconds, aimed at the massive detectors. Once the experiment is fully operational, scientists will catch a precious few each day.

Neutrinos are curious particles. They come in three types, called flavors, and change between them as they travel. The two detectors of the NOvA experiment are placed so far apart to give the neutrinos the time to oscillate from one flavor to another while traveling at nearly the speed of light. Even though only a fraction of the experiment’s larger detector, called the far detector, is fully built, filled with scintillator and wired with electronics at this point, the experiment has already used it to record signals from its first neutrinos.

“That the first neutrinos have been detected even before the NOvA far detector installation is complete is a real tribute to everyone involved. That includes the staff at Fermilab, Ash River Lab and the University of Minnesota module facility, the NOvA scientists, and all of the professionals and students building this detector,” said University of Minnesota physicist Marvin Marshak, Ash River Laboratory director. “This early result suggests that the NOvA collaboration will make important contributions to our knowledge of these particles in the not so distant future.”

Once completed, NOvA’s near and far detectors will weigh 300 and 14,000 tons, respectively. Crews will put into place the last module of the far detector early this spring and will finish outfitting both detectors with electronics in the summer.

“The first neutrinos mean we’re on our way,” said Harvard physicist Gary Feldman, who has been a co-leader of the experiment from the beginning. “We started meeting more than 10 years ago to discuss how to design this experiment, so we are eager to get under way.”

The NOvA collaboration is made up of 208 scientists from 38 institutions in the United States, Brazil, the Czech Republic, Greece, India, Russia and the United Kingdom. The experiment receives funding from the U.S. Department of Energy, the National Science Foundation and other funding agencies.

The NOvA experiment is scheduled to run for six years. Because neutrinos interact with matter so rarely, scientists expect to catch just about 5,000 neutrinos or antineutrinos during that time. Scientists can study the timing, direction and energy of the particles that interact in their detectors to determine whether they came from Fermilab or elsewhere.

Fermilab creates a beam of neutrinos by smashing protons into a graphite target, which releases a variety of particles. Scientists use magnets to steer the charged particles that emerge from the energy of the collision into a beam. Some of those particles decay into neutrinos, and the scientists filter the non-neutrinos from the beam.

Fermilab started sending a beam of neutrinos through the detectors in September, after 16 months of work by about 300 people to upgrade the lab’s accelerator complex.

“It is great to see the first neutrinos from the upgraded complex,” said Fermilab physicist Paul Derwent, who led the accelerator upgrade project. “It is the culmination of a lot of hard work to get the program up and running again.”

Different types of neutrinos have different masses, but scientists do not know how these masses compare to one another. A goal of the NOvA experiment is to determine the order of the neutrino masses, known as the mass hierarchy, which will help scientists narrow their list of possible theories about how neutrinos work.

“Seeing neutrinos in the first modules of the detector in Minnesota is a major milestone,” said Fermilab physicist Rick Tesarek, deputy project leader for NOvA. “Now we can start doing physics.”

Note: NOvA stands for NuMI Off-Axis Electron Neutrino Appearance. NuMI is itself an acronym, standing for Neutrinos from the Main Injector, Fermilab’s flagship accelerator.

Fermilab is America’s premier national laboratory for particle physics 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 @FermilabToday.

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.

Follow the NOvA experiment on Facebook at www.facebook.com/novaexperiment and on Twitter @NOvANuz. To watch the completion of the NOvA far detector live, visit our webcam here: http://www.fnal.gov/pub/webcams/nova_webcam.

Last month the Holometer, Fermilab experiment E-990, reached its design luminosity, building up more than 1 kilowatt of infrared laser power stored in a 40-meter-long Michelson interferometer. This light intensity corresponds to more than 10²² (10 billion trillion) photons per second hitting the interferometer optics. It also allows scientists to measure the optics’ positions to a resolution 1,000 times smaller than the size of a proton.

With this device, physicists hope to discover a new, exotic source of noise: “holographic noise,” which causes a fundamental and unavoidable jitter in the positions of all objects. The new noise, which would limit the ultimate precision of measurements of any type, is believed to originate from a newly postulated law of nature that constrains the maximum information storage capacity of space-time.

Starting with a 1-watt commercial laser beam, researchers achieve the power build-up to 1 kilowatt by recycling the laser’s photons, or particles of light, reflecting used photons back into the interferometer and in effect using each photon 1,000 times before discarding it. The resulting recycled light beam hits the optics with the intensity equivalent of 200,000 laser pointers, causing them to glow brightly (see photograph above) due to scattered light.

When the optics shake due to ground noise, or perhaps due to holographic noise, the motion creates a difference in the path lengths of the two “arms” of the L-shaped interferometer. When the light traveling in the two arms is combined at a common point (at a device called a beam splitter), the changes in the path lengths result in a detectable flickering of the combined beam. The motion of the optics can then be inferred from the flickering.

The Holometer collaboration recently commissioned the devices for measuring this flickering. The high-speed, low-noise detection electronics have demonstrated sensitivity to the extremely subtle holographic noise signal at power levels 100 times lower than typical electronic noise. A characteristic feature of the predicted signal is that its frequency spectrum extends up to megahertz radio frequencies. By focusing on this high-frequency band, the experiment can easily avoid the dominant lower frequency seismic and acoustic noise backgrounds. In fact, the only background noise sources observed so far by the detection system are broadcasts from local AM radio stations, which can be easily identified (using the latest boom box technology) and rejected.

The Holometer team is now addressing the final challenge of shielding the detectors from stray scattered light and is gearing up to begin the holographic noise hunt in earnest. Full speed ahead!

Aaron Chou is a Fermilab scientist on the Holometer experiment.

Calling all nature lovers. How would you like the chance to help diversify one of the oldest prairie restorations in Illinois?

The U.S. Department of Energy’s Fermi National Accelerator Laboratory is looking for volunteers to help with its annual prairie seed harvest. Two harvest events are planned, on Saturday, Oct. 5 and Saturday, Nov. 2, beginning at 10 a.m. Fermilab’s site hosts 1,000 acres of restored native prairie land, and each year community members pitch in to help collect seeds from those native plants.

Less than one-tenth of one percent of native prairies in Illinois remains intact. Fermilab’s restored grassland is one of the largest prairies in the state. The deep-rooted natural grasses of the prairie help prevent erosion and preserve the area’s aquifers.

The main collection area spans about 100 acres, and within it, volunteers will gather seeds from about 25 different types of native plants. Some of those seeds will be used to replenish the Fermilab prairies, filling in gaps where some species are more dominant than others.

“Our objective is to collect seeds from dozens of species,” said Ryan Campbell, an ecologist at Fermilab. “We have more than 1,000 acres of restored grassland, and it’s not all of the same quality. We want to spread diversity throughout the whole site.”

Once the seeds have been collected, the Fermilab roads and grounds staff will store them in a greenhouse and process them for springtime planting, once controlled burns of the prairie have been conducted. The laboratory has also donated some of the seeds to area schools for use in their own prairies and as educational tools.

Fermilab has been hosting the Prairie Harvest every year since 1974, and the event typically draws more than 200 volunteers. The event will last from 10 a.m. to 2 p.m., with lunch provided. Volunteers will be trained on different types of plants and how to harvest seeds. If you have them, bring gloves, a pair of hand clippers and paper grocery bags.

In case of inclement weather, call the Fermilab switchboard at 630-840-3000 to check whether the Prairie Harvest has been canceled. More information on Fermilab’s prairie can be found at http://www.fnal.gov/pub/about/campus/ecology/prairie. For more information on the Prairie Harvest, call the Fermilab Roads and Grounds Department at 630-840-3303.

Fermilab is America’s premier national laboratory for particle physics 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 http://www.fnal.gov and follow us on Twitter at @FermilabToday.

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 http://science.energy.gov.

Tonight, as the sun sinks below the horizon, the world’s most powerful digital camera will once again turn its gleaming eye skyward. Tonight, and for hundreds of nights over the next five years, a team of physicists and astronomers from around the globe will use this remarkable machine to try to answer some of the most fundamental questions about our universe.

On Aug. 31, the Dark Energy Survey (DES) officially began. Scientists on the survey team will systematically map one-eighth of the sky (5000 square degrees) in unprecedented detail. The start of the survey is the culmination of 10 years of planning, building and testing by scientists from 25 institutions in six countries.

The survey’s goal is to find out why the expansion of the universe is speeding up, instead of slowing down due to gravity, and to probe the mystery of dark energy, the force believed to be causing that acceleration.

“The Dark Energy Survey will explore some of the most important questions about our existence,” said James Siegrist, associate director for High Energy Physics at the U.S. Department of Energy’s Office of Science. “In five years’ time, we will be far closer to the answers, and far richer in our knowledge of the universe.”

“With the start of the survey, the work of more than 200 collaborators is coming to fruition,” said DES Director Josh Frieman of the U.S. Department of Energy’s Fermi National Accelerator Laboratory. “It’s an exciting time in cosmology, when we can use observations of the distant universe to tell us about the fundamental nature of matter, energy, space and time.”

The main tool of the survey is the Dark Energy Camera, a 570-megapixel digital camera built at Fermilab in Batavia, Ill., and mounted on the 4-meter Victor M. Blanco telescope at the National Science Foundation’s Cerro Tololo Inter-American Observatory in the Andes Mountains in Chile. The camera includes five precisely shaped lenses, the largest nearly a yard across, that together provide sharp images over its entire field of view.

The Dark Energy Camera is the most powerful survey instrument of its kind, able to see light from more than 100,000 galaxies up to 8 billion light-years away in each snapshot.

“The start of the Dark Energy Survey is an important milestone,” said CTIO Director Nicole van der Bliek. “The Dark Energy Camera, in conjunction with the Blanco telescope here at CTIO, will greatly increase our understanding of the forces that control the expansion of our universe.”

Over five years, the survey will obtain color images of 300 million galaxies and 100,000 galaxy clusters and will discover 4,000 new supernovae, many of which were formed when the universe was half its current size. The data collected will be processed at the National Center for Supercomputing Applications (NCSA) at the University of Illinois in Urbana and then delivered to collaboration scientists and the public.

“NCSA is pleased to be producing and distributing the refined data products that will enable this science,” said Don Petravick, principal investigator of the DES Data Management Operation.

The survey’s observations will not be able to see dark energy directly. However, by studying the expansion of the universe and the growth of large-scale structure over time, the survey will give scientists the most precise measurements to date of the properties of dark energy.

“We’re looking at this big galaxy map of the universe as a way of finding evidence for dark energy and characterizing its nature with cosmic epoch,” said Ofer Lahav of University College London and head of the DES Science Committee. “An even more challenging goal for DES is to tell if what causes the acceleration of the universe is indeed dark energy, or something entirely different.”

The survey will use four methods to probe dark energy:

• Counting galaxy clusters. While gravity pulls mass together to form galaxies, dark energy pulls it apart. The Dark Energy Camera will see light from 100,000 galaxy clusters billions of light-years away. Counting the number of galaxy clusters at different points in time sheds light on this cosmic competition between gravity and dark energy.

• Measuring supernovae. A supernova is a star that explodes and becomes as bright as an entire galaxy of billions of stars. By measuring how bright they appear on Earth, we can tell how far away they are. Scientists can use this information to determine how fast the universe has been expanding since the star’s explosion. The survey will discover 4000 of these supernovae, which exploded billions of years ago in galaxies billions of light-years away.

• Studying the bending of light. When light from distant galaxies encounters dark matter in space, it bends around the matter, causing those galaxies to appear distorted in telescope images. The survey will measure the shapes of 200 million galaxies, revealing the cosmic tug of war between gravity and dark energy in shaping the lumps of dark matter throughout space.

• Using sound waves to create a large-scale map of expansion over time. When the universe was less than 400,000 years old, the interplay between matter and light set off a series of sound waves traveling at nearly two-thirds the speed of light. Those waves left an imprint on how galaxies are distributed throughout the universe. The survey will measure the positions in space of 300 million galaxies to find this imprint and use it to infer the history of cosmic expansion.

The Dark Energy Survey is supported by funding from the U.S. Department of Energy Office of Science; the National Science Foundation; funding agencies in the United Kingdom, Spain, Brazil, Germany and Switzerland; and the participating institutions.

More information about the Dark Energy Survey, including the list of participating institutions, is available at the project website: www.darkenergysurvey.org.

Released by Fermilab, the National Optical Astronomy Observatory (NOAO) and the National Center for Supercomputing Applications on behalf of the Dark Energy Survey collaboration. NOAO is operated by the Association of Universities for Research in Astronomy (AURA), Inc. under cooperative agreement with the National Science Foundation.

Fermilab is America’s premier national laboratory for particle physics 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 @FermilabToday.

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.

Dark Energy Survey: photos and videos

Click on links below images for medium and high-resolution jpeg images. When using this material please credit Fermilab unless noted otherwise.

Members of the Dark Energy Survey collaboration explain what they hope to learn by studying the southern sky with the world’s most advanced digital camera, mounted on a telescope in Chile. Credit: Fermilab

 

After a quarter of a century of searching, physicists have discovered a rare particle decay that gives them an indirect way to test models of new physics.

Researchers on the CMS and LHCb collaborations at the Large Hadron Collider at CERN announced today at the EPS-HEP Conference in Stockholm, Sweden, that their findings agreed closely with the Standard Model of particle physics, ruling out several models that predict new particles.

In this result, physicists showed for the first time enough evidence to declare the discovery of a decay of a particle made up of two kinds of quarks—anti-bottom quarks and strange quarks—into a pair of particles called muons.

The U.S. Department of Energy’s Fermi National Accelerator Laboratory serves as the U.S. hub for more than 1,000 scientists and engineers who participate in the CMS experiment. DOE and the National Science Foundation support involvement by about 2,000 scientists and students from U.S. institutions in the LHC experiments CMS, ATLAS, LHCb and ALICE—the vast majority participating at their home institutions via a powerful broadband network that ships data from CERN.

“This is a victory for the Standard Model,” said CMS physicist Joel Butler of Fermi National Accelerator Laboratory. “But we know the Standard Model is incomplete, so we keep trying to find things that disagree with it.”

The Standard Model predicts that the particle, called B-sub-s, will decay into two muons very rarely, only three times in every billion decays . However, the Standard Model assumes that the only particles involved in the decay are the ones physicists already know. If other, unknown particles exist, they might interfere, either making the decay happen more frequently than predicted or effectively canceling the decay out.

“This is the place to look for new physics,” said LHCb physicist Sheldon Stone of Syracuse University. “Small deviations from the predicted rate would firmly establish the presence of new forces or particles.”

What scientists found was a decay that followed the Standard Model’s predictions almost to the letter. This spells trouble for several models, including a number of models within the theory of supersymmetry, which predicts that each known particle has an undiscovered partner particle.

But the hunters of new particles have not lost hope; the result leaves room for other models of physics beyond the Standard Model to be correct.

The analysis is a tour-de-force for the two LHC experiments, which needed to eliminate an enormous amount of background information generated by other particle decays that mimic the decay they were looking for. The latest results from searches at the ATLAS experiment at CERN and the CDF and DZero experiments at Fermilab are consistent with the results from the LHCb and CMS experiments.

As much as scientists can learn from measuring this decay, they can learn even more if they compare it to the decay of another particle made of quarks: B-sub-d, which is made of an anti-bottom quark and a down quark. A B-sub-d particle should decay even more rarely into a pair of muons than a B-sub-s particle. Physicists did not have enough data to make a definitive statement about this decay in this analysis, but their work shows that they will be able to gather evidence of it after the LHC restarts in 2015 at higher energy.

Background:

Information about the US participation in the LHC is available at http://www.uslhc.us. Follow US LHC on Twitter at http://twitter.com/uslhc.

Fermilab is America’s premier national laboratory for particle physics 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 http://www.fnal.gov and follow us on Twitter at @FermilabToday.

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 http://science.energy.gov.

The National Science Foundation supports the research activities of U.S. university scientists and students on the ATLAS, CMS, LHCb, and ALICE experiments, as well as promoting the development of advanced computing innovations essential to address the data challenges posed by the LHC. For more information, please visit  http://www.nsf.gov.

CERN, the European Organization for Nuclear Research, is the world’s leading laboratory for particle physics. It has its headquarters in Geneva, Switzerland. At present, its Member States are Austria, Belgium, Bulgaria, the Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Italy, the Netherlands, Norway, Poland, Portugal, Slovakia, Spain, Sweden, Switzerland and the United Kingdom. Romania is a candidate for accession. Israel and Serbia are Associate Members in the pre-stage to Membership. India, Japan, the Russian Federation, the United States of America, Turkey, the European Commission and UNESCO have Observer status.

Fermilab plans public celebration to welcome the ring home

For the past month, a 50-foot-wide circular electromagnet has been on a fantastic journey between two U.S. Department of Energy national labs: Brookhaven National Laboratory in New York and Fermi National Accelerator Laboratory in Illinois. On Friday, July 26, that voyage is expected to conclude. Fermilab is planning a party to celebrate the ring’s safe arrival, and everyone’s invited.

The magnet is the centerpiece of Fermilab’s new Muon g-2 experiment, which will study the properties of elusive subatomic particles called muons. The ring was built at Brookhaven National Laboratory in the 1990s for a similar experiment, one which found tantalizing hints of new physics beyond what scientists have observed. Fermilab will conduct a similar experiment with the most powerful beam of muons in the world, an experiment that could open up new realms of scientific discovery.

Moving the ring from New York to Illinois costs roughly 10 times less than building a new one. So the magnet – essentially three rings of aluminum with superconducting coils inside – has spent the last few weeks on a barge, heading down the east coast, around the tip of Florida, into the Gulf of Mexico and then up a series of rivers toward Lemont, Illinois.

It’s been a tricky voyage, because the 17-ton ring cannot be taken apart, or twisted more than a few degrees without irreparably damaging the coils inside.

The ring is expected to arrive in Lemont this weekend, and will be moved from the barge to a specially adapted truck, which will drive it along interstate routes and through suburban streets to Fermilab over three consecutive nights next week. The ring will move at night, using rolling roadblocks to close off intersections, and will utilize portions of I-355 and I-88, along with a series of local roads. Check http://muon-g-2.fnal.gov/bigmove for a map and frequent updates.

The electromagnet is expected to arrive on the Fermilab site early Thursday or Friday morning, July 25 or 26.

“It’s been a very long journey, and it took a lot of work from dozens of people,” said Chris Polly, the project’s manager at Fermilab. “Now that it’s almost here, the excitement is building. We’re eager to get the magnet here and start the experiment.”

On the afternoon of July 26, the ring will move those last few miles across the Fermilab site. The public is invited to come celebrate the ring’s arrival along with Fermilab scientists and employees, starting at 5:30 p.m. at Wilson Hall. There will be hands-on activities for the whole family, and scientists on the Muon g-2 experiment will be on hand to answer questions.

When the ring arrives at Wilson Hall, the action will move outside. Attendees will be able to watch the ring roll past the reflecting pond in front of Wilson Hall, and they will have the opportunity to pose for a massive group photo with the magnet before it moves to its final destination.

“A 50-foot-wide electromagnet rolling down a road is really something to see,” said David Hertzog of the University of Washington, co-spokesman for the Muon g-2 experiment. “As excited as we are about the new physics this experiment may uncover, we’re equally thrilled to see the magnet making its last few steps home.”

Details of the Fermilab celebration are posted on http://muon-g-2.fnal.gov/bigmove, along with a GPS-powered map that shows the location of the magnet on its journey. Updates will be posted to that site, both before and during the move along the Illinois roadways. The celebration could be delayed by inclement weather. Check the Big Move site for updates. For more information, call the Office of Communication at 630-840-3351.

Fermilab is America’s premier national laboratory for particle physics 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 @FermilabToday.

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.

Department of Energy national laboratories collaborate to build the new magnets CERN needs to increase LHC luminosity by an order of magnitude

The U.S. LHC Accelerator Research Program (LARP) has successfully tested a powerful superconducting quadrupole magnet that will play a key role in developing a new beam focusing system for CERN’s Large Hadron Collider (LHC). This advanced system, together with other major upgrades to be implemented over the next decade, will allow the LHC to produce 10 times more high-energy collisions than it was originally designed for.

Dubbed HQ02a, the latest in LARP’s series of High-Field Quadrupole magnets is wound with cables of the brittle but high-performance superconductor niobium tin (Nb3Sn). Compared to the final-focus quadrupoles presently in place at the LHC, which are made with niobium titanium, HQ02a has a larger aperture and superconducting coils designed to operate at a higher magnetic field. In a recent test at the Fermi National Accelerator Laboratory (Fermilab), HQ02a achieved all its challenging objectives.

LARP is a collaboration among the U.S Department of Energy’s Brookhaven National Laboratory (Brookhaven), Fermilab, Lawrence Berkeley National Laboratory (Berkeley Lab), and the SLAC National Accelerator Laboratory (SLAC), working in close partnership with CERN. LARP has also supported research at the University of Texas at Austin and Old Dominion University.

“Congratulation to all the LARP team for this brilliant result,” said Lucio Rossi, leader of the High Luminosity LHC project at CERN. “The steady progress by LARP and the other DOE supported programs clearly shows the benefits of long-term investments to make serious advances in accelerator technology.”

“In the context of the LARP magnet program, this marks the end of the R&D phase and the beginning of the focused development of the magnets that will be installed for the LHC luminosity upgrade,” said Eric Prebys of Fermilab who has served as director of LARP for the last five years. “However, the implications go well beyond that, in that it establishes modern niobium tin as a powerful superconductor for use in accelerator magnets. This success is a tribute to the skill, hard work, and collaborative spirit of all of the people involved.”

Toward future physics at the LHC

Last year’s discovery of the Higgs boson fulfilled one of the major goals of the LHC, arguably the most powerful and complex scientific instrument ever built. Yet precision measurements of the Higgs are still to be made, as well as explorations of new physics including supersymmetry, dark matter, extra dimensions, and other wonders. The LHC’s present complement of Interaction Region Quadrupole magnets, which focus the beams toward the collision points inside the experiments, will reach performance limits well below what’s required for this ambitious physics program. One of the primary goals of LARP is to support CERN’s plan to replace these focusing magnets in about 10 years as part of the High Luminosity LHC project.

The number of useful physics events generated by a collider can be calculated from a parameter called integrated luminosity. For the past decade, CERN has anticipated a series of upgrades that will increase the LHC’s integrated luminosity 10-fold – the goal of the High Luminosity LHC project, consistently recognized as a top priority for the worldwide particle physics program. This goal presents extraordinary challenges, requiring a global effort to push the state of the art in a number of critical technologies.

The most specific need is for more powerful magnets to focus the proton beams at the interaction points. Not only must the magnets produce a stronger field, they will also require a larger temperature margin and have to cope with the intense radiation, which comes hand in hand with the planned increase in the rate of energetic collisions. These requirements go beyond the capabilities of niobium titanium, the material on which all previous accelerator superconducting magnets have been based.

Modern niobium tin is an advanced superconducting material that can operate at a higher magnetic field and with a wider temperature margin than niobium titanium. Unfortunately, niobium tin is brittle and sensitive to strain – critical factors where intense electrical currents and strong magnetic fields create enormous forces as the magnets are energized.

Large forces can damage the fragile conductor or cause sudden displacements of the superconducting coils, releasing energy as heat and possibly resulting in a loss of the magnets’ superconducting state, called a “quench.” When combined temperature, field, and current density cross a critical boundary into ordinary conductivity, the enormous flood of electrons that previously rushed unimpeded through the superconductor slams into a wall of electrical resistance.

Accelerator magnets are designed to withstand these disruptive and potentially damaging events. Nevertheless, the ability to reach the operating level with few or no quenches is an essential performance requirement.

In order to address these challenges, LARP adopted a mechanical support structure based on a thick aluminum shell, pre-tensioned at room temperature using water-pressurized bladders and interference keys. This design concept, developed at Berkeley Lab under the DOE General Accelerator Development program, was compared to the traditional collar-based clamping system originally used in Fermilab’s Tevatron and all subsequent high energy accelerators, and scaled-up to 4 m length in the LARP Long Racetrack and Long Quadrupoles. The HQ models further refined this mechanical design approach, in particular by incorporating full coil alignment.

LARP’s HQ02a is designed like all LHC magnets to operate in superfluid helium at temperatures close to absolute zero. However, it has a larger beam aperture than the present focusing magnets – 120 millimeters in diameter compared to 70 millimeters – and the magnetic field in the superconducting coils that surround the magnet reaches 12 Tesla, 50 percent higher than the present 8 Tesla. The corresponding field gradient, the rate of increase of field strength over the aperture, is 170 Tesla per meter.

Another key objective of the HQ02a design is to minimize any deviations from the precise magnetic field patterns required to focus the beams at the interaction point, and to maintain this high field quality during ramping up to full magnetic field strength. To address these requirements, the LARP High-Field Quadrupole program incorporated a newly designed cable to minimize induced currents, plus precise alignment at all phases of coil fabrication, assembly and magnetic excitation.

“The desired performance characteristics were clearly demonstrated by the test recently completed at Fermilab,” says Berkeley Lab’s GianLuca Sabbi, who directed the HQ02 development. “The magnet quickly achieved its design field gradient with low sensitivity to ramp-rate effects. This result was made possible by the expertise and dedication of many scientists, engineers, and technicians at all the collaborating laboratories.”

As the last step in a decade-long progression of niobium-tin technology advancements by LARP, the sterling performance of HQ02a has reaffirmed the key design elements for focusing magnets that will meet the needs of CERN’s High Luminosity upgrade.

“This is a major step forward in reaching our ultimate goals,” said Bruce Strauss, LARP program manager at DOE’s Office of Science. “It should not be regarded as a single accomplishment but rather the realization of a significant number of individual goals in the design, construction, and testing of Nb 3Sn beam-line magnets.”

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Notes:

The development of HQ02a was a major collaborative undertaking involving the LARP laboratories and their industrial partners. The superconducting niobium-tin wire was manufactured by Oxford Superconducting Technology of New Jersey, cabled at Berkeley Lab, and insulated with a fiberglass sleeve by New England Electric Wire. The coils were wound at Berkeley Lab with parts designed and procured by Fermilab, then sent to Brookhaven Lab for high-temperature reaction and impregnation with epoxy resin. Magnet assembly was performed at Berkeley Lab and the test was performed at Fermilab. Additional tests at Fermilab and CERN are expected in the next months.

Among the key contributors are Dan Dietderich, Arup Ghosh and Arno Godeke for the development, fabrication and characterization of the new cable; Mike Anerella, Franck Borgnolutti, Rodger Bossert, Dan Cheng, Helene Felice, Abdi Salehi, Jesse Schmaltzle, and Miao Yu for the HQ02 magnet design, fabrication, and assembly; Maxim Martchevsky and Prabir Roy for the improved electrical instrumentation and high voltage testing; Guram Chlachidze for planning and execution of the test, together with Joe DiMarco, Darryl Orris, Tiina Salmi, and Xiaorong Wang; Giorgio Ambrosio for contributions to the coil analysis and revision process as the leader of the Long High-Field Quadrupole program; and Ezio Todesco for his support and advice as the magnet work package coordinator in the High Luminosity LHC project.

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.

Fermilab is America’s premier national laboratory for particle physics 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 @FermilabToday.

Lawrence Berkeley National Laboratory addresses the world’s most urgent scientific challenges by advancing sustainable energy, protecting human health, creating new materials, and revealing the origin and fate of the universe. Founded in 1931, Berkeley Lab’s scientific expertise has been recognized with 13 Nobel prizes. The University of California manages Berkeley Lab for the U.S. Department of Energy’s Office of Science. For more, visit www.lbl.gov.

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

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