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Ames Lab Scientists' Surprising Discovery: Making Ferromagnets Stronger by Adding Non-Magnetic Element

Researchers at the U.S. Department of Energy's Ames Laboratory discovered that they could functionalize magnetic materials through a thoroughly unlikely method, by adding amounts of the virtually non-magnetic element scandium to a gadolinium-germanium alloy. It was so unlikely they called it a "counterintuitive experimental finding" in their published work on the research.

Cut U.S. Commercial Building Energy Use 29% with Widespread Controls

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How a Single Chemical Bond Balances Cells Between Life and Death

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New Efficient, Low-Temperature Catalyst for Converting Water and CO to Hydrogen Gas and CO2

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Study Sheds Light on How Bacterial Organelles Assemble

Scientists at Berkeley Lab and Michigan State University are providing the clearest view yet of an intact bacterial microcompartment, revealing at atomic-level resolution the structure and assembly of the organelle's protein shell. This work can help provide important information for research in bioenergy, pathogenesis, and biotechnology.

A Single Electron's Tiny Leap Sets Off 'Molecular Sunscreen' Response

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Researchers Find New Mechanism for Genome Regulation

The same mechanisms that separate mixtures of oil and water may also help the organization of an unusual part of our DNA called heterochromatin, according to a new study by Berkeley Lab researchers. They found that liquid-liquid phase separation helps heterochromatin organize large parts of the genome into specific regions of the nucleus. The work addresses a long-standing question about how DNA functions are organized in space and time, including how genes are silenced or expressed.

The Rise of Giant Viruses

Research reveals that giant viruses acquire genes piecemeal from others, with implications for bioenergy production and environmental cleanup.

Grasses: The Secrets Behind Their Success

Researchers find a grass gene affecting how plants manage water and carbon dioxide that could be useful to growing biofuel crops on marginal land.

SLAC Experiment is First to Decipher Atomic Structure of an Intact Virus with an X-ray Laser

An international team of scientists has for the first time used an X-ray free-electron laser to unravel the structure of an intact virus particle on the atomic level. The method dramatically reduces the amount of virus material required, while also allowing the investigations to be carried out several times faster than before. This opens up entirely new research opportunities.


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Chicago Quantum Exchange to Create Technologically Transformative Ecosystem

The University of Chicago is collaborating with the U.S. Department of Energy's Argonne National Laboratory and Fermi National Accelerator Laboratory to launch an intellectual hub for advancing academic, industrial and governmental efforts in the science and engineering of quantum information.

Department of Energy Awards Six Research Contracts Totaling $258 Million to Accelerate U.S. Supercomputing Technology

Today U.S. Secretary of Energy Rick Perry announced that six leading U.S. technology companies will receive funding from the Department of Energy's Exascale Computing Project (ECP) as part of its new PathForward program, accelerating the research necessary to deploy the nation's first exascale supercomputers.

Cynthia Jenks Named Director of Argonne's Chemical Sciences and Engineering Division

Argonne has named Cynthia Jenks the next director of the laboratory's Chemical Sciences and Engineering Division. Jenks currently serves as the assistant director for scientific planning and the director of the Chemical and Biological Sciences Division at Ames Laboratory.

Argonne-Developed Technology for Producing Graphene Wins TechConnect National Innovation Award

A method that significantly cuts the time and cost needed to grow graphene has won a 2017 TechConnect National Innovation Award. This is the second year in a row that a team at Argonne's Center for Nanoscale Materials has received this award.

Honeywell UOP and Argonne Seek Research Collaborations in Catalysis Under Technologist in Residence Program

Researchers at Argonne are collaborating with Honeywell UOP scientists to explore innovative energy and chemicals production.

Follow the Fantastic Voyage of the ICARUS Neutrino Detector

The ICARUS neutrino detector, born at Gran Sasso National Lab in Italy and refurbished at CERN, will make its way across the sea to Fermilab this summer. Follow along using an interactive map online.

JSA Awards Graduate Fellowships for Research at Jefferson Lab

Jefferson Sciences Associates announced today the award of eight JSA/Jefferson Lab graduate fellowships. The doctoral students will use the fellowships to support their advanced studies at their universities and conduct research at the Thomas Jefferson National Accelerator Facility (Jefferson Lab) - a U.S. Department of Energy nuclear physics laboratory managed and operated by JSA, a joint venture between SURA and PAE Applied Technologies.

Muon Magnet's Moment Has Arrived

On May 31, the 50-foot-wide superconducting electromagnet at the center of the Muon g-2 experiment saw its first beam of muon particles from Fermilab's accelerators, kicking off a three-year effort to measure just what happens to those particles when placed in a stunningly precise magnetic field. The answer could rewrite scientists' picture of the universe and how it works.

Seven Small Businesses to Collaborate with Argonne to Solve Technical Challenges

Seven small businesses have been selected to collaborate with researchers at Argonne to address technical challenges as part of DOE's Small Business Vouchers Program.

JSA Names Charles Perdrisat and Charles Sinclair as Co-Recipients of its 2017 Outstanding Nuclear Physicist Prize

Jefferson Science Associates, LLC, announced today that Charles Perdrisat and Charles Sinclair are the recipients of the 2017 Outstanding Nuclear Physicist Prize. The 2017 JSA Outstanding Nuclear Physicist Award is jointly awarded to Charles Perdrisat for his pioneering implementation of the polarization transfer technique to determine proton elastic form factors, and to Charles Sinclair for his crucial development of polarized electron beam technology, which made such measurements, and many others, possible.


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Oxygen: The Jekyll and Hyde of Biofuels

Scientists are devising ways to protect plants, biofuels and, ultimately, the atmosphere itself from damage caused by an element that sustains life on earth.

The Rise of Giant Viruses

Research reveals that giant viruses acquire genes piecemeal from others, with implications for bioenergy production and environmental cleanup.

Grasses: The Secrets Behind Their Success

Researchers find a grass gene affecting how plants manage water and carbon dioxide that could be useful to growing biofuel crops on marginal land.

New Perspectives Into Arctic Cloud Phases

Teamwork provides insight into complicated cloud processes that are important to potential environmental changes in the Arctic.

Mountaintop Plants and Soils to Become Out of Sync

Plants and soil microbes may be altered by climate warming at different rates and in different ways, meaning vital nutrient patterns could be misaligned.

If a Tree Falls in the Amazon

For the first time, scientists pinpointed how often storms topple trees, helping to predict how changes in Amazonia affect the world.

Turning Waste into Fuels, Microbial Style

A newly discovered metabolic process linking different bacteria in a community could enhance bioenergy production.

Department of Energy Awards Six Research Contracts Totaling $258 Million to Accelerate U.S. Supercomputing Technology

Today U.S. Secretary of Energy Rick Perry announced that six leading U.S. technology companies will receive funding from the Department of Energy's Exascale Computing Project (ECP) as part of its new PathForward program, accelerating the research necessary to deploy the nation's first exascale supercomputers.

Electrifying Magnetism

Researchers create materials with controllable electrical and magnetic properties, even at room temperature.

One Step Closer to Practical Fast Charging Batteries

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Rare Supernova Discovery Ushers in New Era for Cosmology

Article ID: 673270

Released: 2017-04-19 14:50:57

Source Newsroom: Lawrence Berkeley National Laboratory

  • Credit: (Image Credit: Joel Johansson, Stockholm University)

    This composite image shows the gravitationally lensed type Ia supernova iPTF16geu, as seen with different telescopes. The background image shows a wide-field view of the night sky as seen with the Palomar Observatory located on Palomar Mountain, California. Far Left Image: Captured by the Sloan Digital Sky Survey, this optical light observation shows the lens galaxy and its surrounding environment in the sky. Center Left Image: Captured by the Hubble Space Telescope, this is a 20x zoom infrared image of the lens galaxy. Center Right Image: Captured by the Hubble Space Telescope, this 5x optical light zoom reveals the four gravitationally lensed images of iPTF16geu. Far Right Image: Captured by the Keck Telescope, this infrared observation features the four gravitationally lensed images of iPTF16geu and the gravitational “arc” of its host galaxy.

With the help of an automated supernova-hunting pipeline and a galaxy sitting 2 billion light years away from Earth that’s acting as a “magnifying glass,’’ astronomers have captured multiple images of a Type Ia supernova—the brilliant explosion of a star—appearing in four different locations on the sky. So far this is the only Type Ia discovered that has exhibited this effect.

 This phenomenon called ‘gravitational lensing’ is an effect of Einstein’s Theory of Relativity—mass bends light. This means that the gravitational field of a massive object—like a galaxy—can bend light rays that pass nearby and refocus them somewhere else, causing background objects to appear brighter and sometimes in multiple locations. Astrophysicists believe that if they can find more of these magnified Type Ia’s, they may be able to measure the rate of the Universe’s expansion to unprecedented accuracy and shed some light on the distribution of matter in the cosmos.

 Fortunately, by taking a closer look at the properties of this rare event, two Lawrence Berkeley National Laboratory (Berkeley Lab) researchers have come up with a method—a pipeline— for identifying more of these so-called “strongly lensed Type Ia supernovae” in existing and future wide-field surveys. A paper describing their approach was recently published in the Astrophysical Journal Letters. Meanwhile, a paper detailing the discovery and observations of the 4 billion year old Type Ia supernova, iPTF16geu, will be published in Science on April 21.

“It is extremely difficult to find a gravitationally lensed supernova, let alone a lensed Type Ia. Statistically, we suspect that there may be approximately one of these in every 50,000 supernovae that we identify,” says Peter Nugent, an astrophysicist in Berkeley Lab’s Computational Research Division (CRD) and an author on both papers. “But since the discovery of iPTF16geu, we now have some thoughts on how to improve our pipeline to identify more of these events.”

Cosmic Surprise Sheds New Light on Cosmology

For many years, the transient nature of supernovae made them extremely difficult to detect. Thirty years ago, the discovery rate was about two per month. But thanks to the Intermediate Palomar Transient Factory (iPTF), a new survey with an innovative pipeline, these events are being detected daily, some within hours of when their initial explosions appear.

The process of identifying transient events, like supernovae, begins every night at the Palomar Observatory in Southern California, where a wide-field camera mounted on the robotic Samuel Oschin Telescope scans the sky. As soon as observations are taken, the data travel more than 400 miles to the Department of Energy’s (DOE’s) National Energy Research Scientific Computing Center (NERSC), which is located at Berkeley Lab. At NERSC, machine learning algorithms running on the facility’s supercomputers sift through the data in real-time and identify transients for researchers to follow up on.

On September 5, 2016, the pipeline identified iPTF16geu as a supernova candidate. At first glance, the event didn’t look particularly out of the ordinary. Nugent notes that many astronomers thought it was just a typical Type Ia supernova sitting about 1 billion light years away from Earth.

 Like most supernovae that are discovered relatively early on, this event got brighter with time. Shortly after it reached peak brightness (19th magnitude) Stockholm University Professor in Experimental Particle Astrophysics Ariel Goobar decided to take a spectrum—or detailed light study—of the object. The results confirmed that the object was indeed a Type Ia supernova, but they also showed that, surprisingly, it was located 4 billion light years away. A second spectrum taken with the OSIRIS instrument on the Keck telescope on Mauna Kea, Hawaii, showed without a doubt that the supernova was 4 billion light years away, and also revealed its host galaxy and another galaxy located about 2 billion light years away that was acting as a gravitational lens, which amplified the brightness of the supernova and caused it to appear in four different places on the sky.

“I’ve been looking for a lensed supernova for about 15 years. I looked in every possible survey, I’ve tried a variety of techniques to do this and essentially gave up, so this result came as a huge surprise,” says Goobar, who is lead author of the Science paper. “One of the reasons I’m interested in studying gravitational lensing is that it allows you to measure the structure of matter—both visible and dark matter—at scales that are very hard to get.”

According to Goobar, the survey at Palomar was set up to look at objects in the nearby Universe, about 1 billion light years away. But finding a distant Type Ia supernova in this survey allowed researchers to follow up with even more powerful telescopes that resolved small-scale structures in the supernova host galaxy, as well as the lens galaxy that is magnifying it.

 “There are billions of galaxies in the observable universe and it takes a tremendous effort to look in a very small patch of the sky to find these kind of events. It would be impossible to find an event like this without a magnified supernova directing you where to look,” says Goobar. “We got very lucky with this discovery because we can see the small scale structures in these galaxies, but we won’t know how lucky we are until we find more of these events and confirm that what we are seeing isn’t an anomaly.”

 Another benefit of finding more of these events is that they can be used as tools to precisely measure the expansion rate of the Universe. One of the keys to this is gravitational lensing. When a strong gravitational lens produces multiple images of a background object, each image's light travels a slightly different path around the lens on its way to Earth. The paths have different lengths, so light from each image takes a different amount of time to arrive at Earth.

 “If you measure the arrival times of the different images, that turns out to be a good way to measure the expansion rate of the Universe,” says Goobar. “When people measure the expansion rate of the Universe now locally using supernovae or Cepheid stars they get a different number from those looking at early universe observations and the cosmic microwave background. There is tension out there and it would be neat if we could contribute to resolving that quest.”

New Methods Sniff Out Lensed Supernovae

 According to Danny Goldstein, a UC Berkeley astronomy graduate student and an author of the Astrophysical Journal letter, there have only been a few gravitationally lensed supernovae of any type ever discovered, including iPTF16geu, and they’ve all been discovered by chance.

“By figuring out how to systematically find strongly lensed Type Ia supernovae like iPTF16geu, we hope to pave the way for large-scale lensed supernova searches, which will unlock the potential of these objects as tools for precision cosmology,” says Goldstein, who worked with Nugent to devise a method of for finding them in existing and upcoming wide-field surveys.  

 The key idea of their technique is to use the fact that Type Ia supernovae are “standard candles”—objects with the same intrinsic brightness—to identify ones that are magnified by lensing. They suggest starting with supernovae that appear to go off in red galaxies that have stopped forming stars. These galaxies only host Type Ia supernovae and make up the bulk of gravitational lenses. If a supernova candidate that appears to be hosted in such a galaxy is brighter than the "standard" brightness of a Type Ia supernova, Goldstein and Nugent argue that there is a strong chance the supernova does not actually reside in the galaxy, but is instead a background supernova lensed by the apparent host.

“One of the innovations of this method is that we don’t have to detect multiple images to infer that a supernova is lensed,” says Goldstein. “This is a huge advantage that should enable us to find more of these events than previously thought possible."

 Using this method, Nugent and Goldstein predict that the upcoming Large Synoptic Survey Telescope should be able to detect about 500 strongly lensed Type Ia supernovae over the course of 10 years—about 10 times more than previous estimates. Meanwhile, the Zwicky Transient Facility, which begins taking data in August 2017 at Palomar, should find approximately 10 of these events in a three-year search. Ongoing studies show that each lensed Type Ia supernova image has the potential to make a four percent, or better, measurement of the expansion rate of the universe. If realized, this could add a very powerful tool to probe and measure the cosmological parameters.  

“We are just now getting to the point where our transient surveys are big enough, our pipelines are efficient enough, and our external data sets are rich enough that we can weave through the data and get at these rare events,” adds Goldstein. “It’s an exciting time to be working in this field.”

iPTF is a scientific collaboration between Caltech; Los Alamos National Laboratory; the University of Wisconsin, Milwaukee; the Oskar Klein Centre in Sweden; the Weizmann Institute of Science in Israel; the TANGO Program of the University System of Taiwan; and the Kavli Institute for the Physics and Mathematics of the Universe in Japan. NERSC is a DOE Office of Science User Facility.