Cosmic rays Hotspot: Physicists closer to finding the mysterious sources

This map of the northern sky shows cosmic ray concentrations, with a "hotspot" with a disproportionate number of cosmic rays shown as the bright red and yellow spot, upper right. 

An international team of physicists using the University of Utah-operated Telescope Array near Delta, Utah, say their discovery of the hotspot should narrow the search for the mysterious source or sources of ultrahigh-energy cosmic rays, which carry more energy than any other known particle in the universe. 

Credit: Kazumasa Kawata, University of Tokyo Institute for Cosmic Ray Research.

An observatory run by the University of Utah found a "hotspot" beneath the Big Dipper emitting a disproportionate number of the highest-energy cosmic rays.

The discovery moves physics another step toward identifying the mysterious sources of the most energetic particles in the universe.

Gordon Thomson

"This puts us closer to finding out the sources, but no cigar yet," says University of Utah physicist Gordon Thomson, spokesman and co-principal investigator for the $25 million Telescope Array cosmic ray observatory west of Delta, Utah; the Northern Hemisphere's largest cosmic ray detector.

"All we see is a blob in the sky, and inside this blob there is all sorts of stuff – various types of objects, that could be the source" of the powerful cosmic rays, he adds. "Now we know where to look."

A new study identifying a hotspot in the northern sky for ultrahigh-energy cosmic rays has been accepted for publication by Astrophysical Journal Letters.

Thomson says many astrophysicists suspect ultrahigh-energy cosmic rays are generated by active galactic nuclei (AGNs), in which material is sucked into a supermassive black hole at the center of galaxy, while other material is spewed away in a beam-like jet known as a blazar.

Another popular possibility is that the highest-energy cosmic rays come from some supernovas (exploding stars) that emit gamma rays bursts.

Lower-energy cosmic rays come from the sun, other stars and exploding stars, but the source or sources of the most energetic cosmic rays has been a decades-long mystery.

The study was conducted by 125 researchers in the Telescope Array project, including Thomson and 31 other University of Utah physicists, plus 94 other scientists from the University of Tokyo (ICRR) and 28 other research institutions in Japan, the United States, South Korea, Russia and Belgium.

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More Information: Indications of Intermediate-Scale Anisotropy of Cosmic Rays with Energy Greater Than 57 EeV in the Northern Sky Measured with the Surface Detector of the Telescope Array Experiment - Authors: K. Kawata, et al.

Physicists Debate Discovery of Gravitational Ripples from the Big Bang

This artist's illustration depicts the creation of gravitational waves from two orbiting black holes as ripples in space-time. 

In March 2014, astronomers announced the first detection of long-sought gravitational waves, though some critics now say the finding could be merely dust.

Credit: NASA

The physics world was agog in March over the announcement that astronomers had possibly found ripples in space-time from the earliest moments of the universe but some scientists now question whether the findings may be nothing more than galactic dust.

If the finding of these ripples, or primordial gravitational waves, is confirmed, it would represent the best evidence yet for inflation, the idea that the universe underwent an explosive burst in size in the earliest fractions of a second after the Big Bang.

If the findings are discounted, inflation could still be correct, but scientists must provide other evidence.

A panel of well-known cosmologists debated the discovery and the model of cosmic inflation itself at an event here on Friday (May 30) at the World Science Festival, moderated by theoretical physicist Brian Greene of Columbia University in New York.

Physicists monitoring huge solar event - Magnetic Field Reversal - Video

The sun's magnetic field is poised to reverse its polarity. The effects of the event will be closely monitored by Stanford solar physicists. Credit: Kurt Hickman

The sun's magnetic field is poised to reverse its polarity. The effects of the event, which occurs every 11 years, will ripple throughout the solar system and be closely monitored by Stanford solar physicists.

Every 11 years, the sun undergoes a complete makeover when the polarity of its magnetic field – its magnetic north and south – flips. The effects of this large-scale event ripple throughout the solar system.

Although the exact internal mechanism that drives the shift is not entirely understood, researchers at Stanford's Wilcox Solar Observatory have monitored the sun's magnetic field on a daily basis since 1975 and can identify the process as it occurs on the sun's surface. This will be the fourth shift the observatory has monitored.

New polarity builds up throughout the 11-year solar cycle as sunspots – areas of intense magnetic activity – appear as dark blotches near the equator of the sun's surface.

Over the course of a month, a sunspot spreads out, and gradually that magnetic field migrates from the equator to one of the sun's poles.


As the polarity moves toward the pole, it erodes the existing, opposite polarity, said Todd Hoeksema, a solar physicist at Stanford since 1978 and director of the Wilcox Solar Observatory.

The magnetic field gradually reduces toward zero, and then rebounds with the opposite polarity.

"It's kind of like a tide coming in or going out," Hoeksema said. "Each little wave brings a little more water in, and eventually you get to the full reversal."

The effects of this event are widespread: The area of space where the sun's magnetic field exerts its influence – called the heliosphere – stretches well beyond Pluto, past NASA's Voyager probes near the edge of interstellar space.

The sun is also typically at the peak of its activity during a magnetic field reversal, which, in addition to an increased number of sunspots, is marked by a surge in solar flares and mass ejections.

The sun's changing magnetic field and the bursts of charged particles can interact with Earth's own magnetic field, one manifestation of which is a noticeable uptick in the occurrence and range of auroras.

Earth's magnetic field can also affect major electronic systems, Hoeksema said, such as power distribution grids and GPS satellites, so scientists are keen to monitor the heliosphere.

"We also see the effects of this on other planets," Hoeksema said. "Jupiter has storms, Saturn has auroras, and this is all driven by activity of the sun."

'Supersymmetry' Could Be The Next Next Big Thing In Physics

Physicists said the next big thing in the world of particle physics will be the extension of the standard model of particle physics known as supersymmetry or SUSY.

According to a team of researchers, the better understanding of the universe will lead to the outgrowth of the discovery of the Higgs boson, and will lead to the discovery of its extension, the SUSY.

University of Oklahoma researchers said SUSY predict new matter states or super partners for each matter particle already accounted for in the standard model.

Physicists Howard Baer, Homer L. Dodge Professor of High Energy Physics in the OU Department of Physics and Astronomy, and his colleagues were the first in the world to show what SUSY matter might look like at colliding beam experiments.

Earlier reports said the Large Hadron Collider has not been successful so far in finding SUSY, while Atlas and CMS experiments is expected to provide new analysis on SUSY in March 2012.

The LHC will reportedly double the energy required to prove the SUSY theory.

Baer, who has studied SUSY for 25 years, said the discovery of the Higgs boson will open the door to a whole new world of super particles. "Finding the Higgs boson is like looking for a needle in a haystack, but the Higgs boson is only the tip of the iceberg of SUSY matter," Baer said.

"With SUSY, we are talking about the next level of the laws of physics. If there is SUSY, then we will find super partners, which will provide a new perspective for the origin and evolution of the universe. At that point, we can say we are on the road to a much deeper comprehension of nature, " Baer added.

The researchers said SUSY may be the next big step in understanding cosmology and the origin of dark matter, the so-called invisible particles that dominate the matter density of the universe

'A Universe From Nothing' by Lawrence Krauss

Canadian Physicists predict cooler computers

Canadian physicists say they have discovered new behaviours of light occurring within photonic crystals.

University of Toronto quantum optics researchers Professor Sajeev John and doctoral student Xun Ma said their findings could lead to faster optical information processing and compact computers that don't overheat.

"We discovered that by sculpting a unique artificial vacuum inside a photonic crystal, we can completely control the electronic state of artificial atoms within the vacuum," Ma, lead author of the study, said. "This discovery can enable photonic computers that are more than 100 times faster than their electronic counterparts, without heat dissipation issues and other bottlenecks currently faced by electronic computing."

John said he and Ma designed a vacuum in which light passes through circuit paths whose character changes drastically and abruptly with the wave length of the light.

"A vacuum experienced by light is not completely empty, and can be made even emptier," said John. "It's not the traditional understanding of a vacuum."

Ma added: "In this vacuum, the state of each atom -- or quantum dot -- can be manipulated with color-coded streams of laser pulses that sequentially excite and de-excite it in trillionths of a second. These quantum dots can in turn control other streams of optical pulses, enabling optical information processing and computing."

The research is reported in the journal Physical Review Letters.