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IceCube telescope: Extreme science meets extreme electronics

Junko Yoshida
EE Times

(06/23/2010 12:05 PM EDT)

MADISON, Wis. — The world’s largest telescope, currently under construction more than a mile beneath the Antarctic ice, is on schedule to be completed next year, according to a researcher at the University of Wisconsin, the lead institution for a scientific project called IceCube.

Ninety-five percent of the IceCube telescope, consisting of thousands of digital optical modules developed for scientists working to understand the universe, is already installed and operating at the South Pole, said Albrecht Karle, a physics professor at the University of Wisconsin-Madison in an interview with EE Times.

The IceCube telescope is no ordinary apparatus. With a volume of one cubic kilometer, the instrument is pointed not to the sky, but downward towards the center of the Earth, buried beneath tons of ice in the coldest spot in the world. No one will ever “look through” this telescope. Instead, it will convey its findings through vast arrays of digital sensors.

Scientists backed by the National Science Foundation are looking for very small, very elusive particles called neutrinos that can tell scientists much more about the universe than photons or charged particles.

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US experiment hints at 'multiple God particles'

By Paul Rincon

Science reporter, BBC News

There may be multiple versions of the elusive "God particle" - or Higgs boson - according to a new study.

Finding the Higgs is the primary aim of the £6bn ($10bn) Large Hadron Collider (LHC) experiment near Geneva.

But recent results from the LHC's US rival suggest physicists could be hunting five particles, not one.

The data may point to new laws of physics beyond the current accepted theory - known as the Standard Model.

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New measurements from Fermilab’s MINOS experiment suggest a difference in a key property of neutrinos and antineutrinos

BATAVIA, Illinois-Scientists of the MINOS experiment at the Department of Energy’s Fermi National Accelerator laboratory today (June 14) announced the world’s most precise measurement to date of the parameters that govern antineutrino oscillations, the back-and-forth transformations of antineutrinos from one type to another. This result provides information about the difference in mass between different antineutrino types. The measurement showed an unexpected variance in the values for neutrinos and antineutrinos. This mass difference parameter, called Δm² (“delta m squared”), is smaller by approximately 40 percent for neutrinos than for antineutrinos.

However, there is a still a five percent probability that Δm² is actually the same for neutrinos and antineutrinos. With such a level of uncertainty, MINOS physicists need more data and analysis to know for certain if the variance is real.

Neutrinos and antineutrinos behave differently in many respects, but the MINOS results, presented today at the Neutrino 2010 conference in Athens, Greece, and in a seminar at Fermilab, are the first observation of a potential fundamental difference that established physical theory could not explain.

“Everything we know up to now about neutrinos would tell you that our measured mass difference parameters should be very similar for neutrinos and antineutrinos,” said MINOS co-spokesperson Rob Plunkett. “If this result holds up, it would signal a fundamentally new property of the neutrino-antineutrino system. The implications of this difference for the physics of the universe would be profound.”

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International team discovers element 117

An international team of scientists from Russia and the United States, including two Department of Energy national laboratories and two universities, has discovered the newest superheavy element, element 117.

The team included scientists from the Joint Institute of Nuclear Research (Dubna, Russia), the Research Institute for Advanced Reactors (Dimitrovgrad), Lawrence Livermore National Laboratory, Oak Ridge National Laboratory, Vanderbilt University, and the University of Nevada, Las Vegas.

“The discovery of element 117 is the culmination of a decade-long journey to expand the periodic table and write the next chapter in heavy element research,” said Academician Yuri Oganessian, scientific leader of the Flerov Laboratory of Nuclear Reactions at JINR and spokesperson for the collaboration.

The team established the existence of element 117 from decay patterns observed following the bombardment of a radioactive berkelium target with calcium ions at the JINR U400 cyclotron in Dubna. The experiment depended on the availability of special detection facilities and dedicated accelerator time at Dubna, unique isotope production and separation facilities at Oak Ridge, and distinctive nuclear data analysis capabilities at Livermore.

“This is a significant breakthrough for science,” LLNL director George Miller said. “The discovery of a new element provides new insight into the makeup of the universe and is a testimony to the strength of science and technology at the partner institutions.”

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Ultra-powerful Laser Makes Silicon Pump Liquid Uphill with No Added Energy

Researchers at the University of Rochester's Institute of Optics have discovered a way to make liquid flow vertically upward along a silicon surface, overcoming the pull of gravity, without pumps or other mechanical devices.

In a paper in the journal Optics Express, professor Chunlei Guo and his assistant Anatoliy Vorobyev demonstrate that by carving intricate patterns in silicon with extremely short, high-powered laser bursts, they can get liquid to climb to the top of a silicon chip like it was being sucked through a straw.

Unlike a straw, though, there is no outside pressure pushing the liquid up; it rises on its own accord. By creating nanometer-scale structures in silicon, Guo greatly increases the attraction that water molecules feel toward it. The attraction, or hydrophile, of the silicon becomes so great, in fact, that it overcomes the strong bond that water molecules feel for other water molecules.

Thus, instead of sticking to each other, the water molecules climb over one another for a chance to be next to the silicon. (This might seem like getting energy for free, but even though the water rises, thus gaining potential energy, the chemical bonds holding the water to the silicon require a lower energy than the ones holding the water molecules to other water molecules.) The water rushes up the surface at speeds of 3.5 cm per second.

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Exotic Antimatter Detected at Relativistic Heavy Ion Collider (RHIC)

Scientists report discovery of heaviest known antinucleus and first antinucleus containing an anti-strange quark, laying the first stake in a new frontier of physics

March 4, 2010

UPTON, NY — An international team of scientists studying high-energy collisions of gold ions at the Relativistic Heavy Ion Collider (RHIC), a 2.4-mile-circumference particle accelerator located at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory, has published evidence of the most massive antinucleus discovered to date. The new antinucleus, discovered at RHIC’s STAR detector, is a negatively charged state of antimatter containing an antiproton, an antineutron, and an anti-Lambda particle. It is also the first antinucleus containing an anti-strange quark. The results will be published online by Science Express on March 4, 2010.

“This experimental discovery may have unprecedented consequences for our view of the world,” commented theoretical physicist Horst Stoecker, Vice President of the Helmholtz Association of German National Laboratories. “This antimatter pushes open the door to new dimensions in the nuclear chart — an idea that just a few years ago, would have been viewed as impossible.”

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Additional story.

Sonic laser or "Saser"

Wed, 17 Jun 2009 11:30:00 GMT

PA163/09

It was an idea born out of curiosity in the physics lab, but now a new type of ‘laser’ for generating ultra-high frequency sound waves instead of light has taken a major step towards becoming a unique and highly useful 21st century technology.

Scientists at The University of Nottingham, in collaboration with colleagues in the Ukraine, have produced a new type of acoustic laser device called a Saser. It’s a sonic equivalent to the laser and produces an intense beam of uniform sound waves on a nano scale. The new device could have significant and useful applications in the worlds of computing, imaging, and even anti-terrorist security screening.

Where a ‘laser’,(Light Amplification by the Stimulated Emission of Radiation), uses packets of electromagnetic vibrations called ‘photons’, the ‘Saser’ uses sound waves composed of sonic vibrations called ‘phonons’. In a laser, the photon beam is produced by stimulating electrons with an external power source so they release energy when they collide with other photons in a highly reflective optical cavity. This produces a coherent and controllable shining beam of laser light in which all the photons have the same frequency and rate of oscillation. From supermarket scanners to DVD players, surgery, manufacturing and the defence industry, the application of laser technology is widespread.

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Evidence of macroscopic quantum tunneling detected in nanowires

5/27/09

Phil Ciciora, News Editor
217-333-2177;pciciora@illinois.edu

CHAMPAIGN, Ill. — A team of researchers at the University of Illinois has demonstrated that, counter to classical Newtonian mechanics, an entire collection of superconducting electrons in an ultrathin superconducting wire is able to “tunnel” as a pack from a state with a higher electrical current to one with a notably lower current, providing more evidence of the phenomenon of macroscopic quantum tunneling.

Physics professors Alexey Bezryadin and Paul Goldbart led the team, with graduate student Mitrabhanu Sahu performing the bulk of the measurements. Their research was published on the Web site of the journal Nature Physics on May 17.

Quantum tunneling is the capability of a particle to inhabit regions of space that would normally be off-limits according to classical mechanics. This research observes a process called a quantum phase slip, whereby packs of roughly 100,000 electrons tunnel together from higher electrical current states to lower ones. The energy locked in the motion of the electrons as they phase slip is dissipated as heat, causing the nanowires to switch from a superconducting state to a more highly resistive one.

It’s through this switching of states that allows the tunneling of the phase slip to be observed, the researchers say.

Full story.

UWM scientists develop techniques to unravel proteins' mysteries

By Mark Johnson of the Journal Sentinel

Posted: Mar. 30, 2009

Proteins, the work-horse molecules necessary for virtually every human action from breathing to thinking, have proved an almost ghostly presence, daring scientists to fully grasp their structure and behavior.

Now, physicists at the University of Wisconsin-Milwaukee have developed powerful imaging techniques that promise to tell us much more about what proteins are and what they do, how they change shapes and how they work together in a cell.

Such questions go to the heart of our quest to understand diseases and find effective drugs.

"The vast majority of diseases are caused by impairment in some kind of protein function - too much or not enough of a certain protein, or a protein that's not working properly," said Andy Greene, director of the Biotechnology and Bioengineering Center at the Medical College of Wisconsin, who was not involved in the UWM work.

Using X-rays, lasers, powerful microscopes and mathematical equations, the UWM scientists have attacked the task of protein-watching on two fronts, publishing papers in the journals Nature Physics and Nature Photonics.

One group led by Valerica Raicu, an assistant physics professor, has discovered a novel way to eavesdrop on the interactions between one protein and another. These communications between proteins are considered vital to understanding what happens inside a living cell.

A second group, led by Abbas Ourmazd, professor of physics and electrical engineering, has developed what may be a vastly improved method of viewing the atomic structure of a single protein.

Full story.

Fermilab collider experiments discover rare single top quark

Batavia, Ill.—Scientists of the CDF and DZero collaborations at the Department of Energy’s Fermi National Accelerator Laboratory have observed particle collisions that produce single top quarks. The discovery of the single top confirms important parameters of particle physics, including the total number of quarks, and has significance for the ongoing search for the Higgs particle at Fermilab’s Tevatron, currently the world’s most powerful operating particle accelerator.

Previously, top quarks had only been observed when produced by the strong nuclear force. That interaction leads to the production of pairs of top quarks. The production of single top quarks, which involves the weak nuclear force and is harder to identify experimentally, has now been observed, almost 14 years to the day of the top quark discovery in 1995.

Searching for single-top production makes finding a needle in a haystack look easy. Only one in every 20 billion proton-antiproton collisions produces a single top quark. Even worse, the signal of these rare occurrences is easily mimicked by other “background” processes that occur at much higher rates.

"Observation of the single top quark production is an important milestone for the Tevatron program," said Dr. Dennis Kovar, Associate Director of the Office of Science for High Energy Physics at the U.S. Department of Energy. "Furthermore, the highly sensitive and successful analysis is an important step in the search for the Higgs."

Discovering the single top quark production presents challenges similar to the Higgs boson search in the need to extract an extremely small signal from a very large background. Advanced analysis techniques pioneered for the single top discovery are now in use for the Higgs boson search. In addition, the single top and the Higgs signals have backgrounds in common, and the single top is itself a background for the Higgs particle.

Full story.