Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

IceCube provides proof of neutrinos from the cosmos – Start of the neutrino astronomy era

22.11.2013
IceCube particle detector at the South Pole discovers 28 high-energy neutrinos / Publication in SCIENCE

The IceCube Neutrino Observatory at the South Pole was the first to discover ultrahigh-energy neutrinos which most likely were the result of cosmic acceleration in outer space. "After more than a decade of intense searching, we can now announce that we have found neutrinos that were very probably generated in the vast expanses of outer space", reported Professor Lutz Köpke of Johannes Gutenberg University Mainz (JGU).


View over the ice at the geographic South Pole to the above-ground measuring station for the IceCube experiment. The data from the photo sensors embedded in the ice are extracted and analyzed in computer farms. The picture comes from the dusk phase during the transition from the Antarctic winter (sun below the horizon) to the Antarctic summer (sun above the horizon).
source: Sven Lindstrom, IceCube/NSF

Neutrinos are electrically neutral particles with tiny mass. High-energy neutrinos may be generated in the proximity of black holes and are subsequently accelerated to acquire their extraordinary energies. They can then travel through space almost completely unhindered. On the downside, they are very difficult to detect. The IceCube experiment has now found 28 neutrinos with energy greater than 50 tera-electron volts (TeV) all of which landed in the Antarctic ice between May 2010 and May 2012.

"This discovery was one of the key objectives of the IceCube experiment. It is fantastic that we have now reached this milestone, and in a way it is a relief as well," said Köpke, who has been searching for astrophysical neutrinos for more than 13 years and served as an internal reviewer as the final analysis was scrutinized.

The IceCube Neutrino Observatory is composed of 5,160 optical sensors placed in the Antarctic ice. Together they cover one cubic kilometer of clear South Polar ice. The high-precision optical sensors can detect weak flashes of blue light, also known as Cherenkov radiation, which is generated if neutrinos react near a detector and produce charged particles. The detector was completed in late 2010 and provides data around the clock. It is currently the largest facility designed to search for neutrinos from outer space.

Even though a few neutrinos were discovered in 1987 after the explosion of a supernova in the Large Magellanic Cloud, their energy was about a million times less than the particles that were justdiscovered. "Some of the neutrinos we have now detected have a thousand times more energy than neutrinos created in particle accelerators on earth," explained Köpke. "Only a third of the 28 high-energy neutrinos could have been generated by cosmic radiation in the Earth's atmosphere."

Unlike light, neutrinos can penetrate space dust unhindered and can even penetrate our planet Earth. In doing so, neutrinos provide information about their far-away sources. The highest energy neutrinos can be detected with IceCube, regardless of the direction they came from. "Over the next ten years we will continue to gather data which will tell us more about the origin of cosmic radiation and the unique properties of the neutrinos," said Köpke.

High-energy neutrinos as messengers from outer space

Billions of neutrinos penetrate every square centimeter of the Earth. Most are generated in the sun or in the Earth's atmosphere, which is constantly being bombarded with cosmic radiation. Neutrinos from further afield inside or outside of our galaxy are much rarer.

The existence of such neutrinos and the process that leads to their creation in the proximity of supernovas, black holes, pulsars, active galaxies, or other extreme extra-galactic phenomena have been discussed in many scientific papers. The IceCube Observatory was specifically developed to examine the frequency and type of high-energy neutrinos as well as to gain an understanding of their origins.

The findings with a significance greater than four standard deviations now published in Science illustrate that the neutrinos observed have properties that clearly indicate an origin in cosmic accelerators. “The decisive analysis was carried out by a group of postdoctoral researchers and doctoral candidates at the University of Wisconsin in Madison, Wisconsin, USA, two of whom were German. Work is now being done to improve the precision of the observations and to understand what the signal means and where it comes from," explained Köpke.

The IceCube Neutrino Observatory at the geographic South Pole was completed in December 2010 after seven years of construction, on time and within budget. The American National Science Foundation (NSF) financed the instrumentation and the German Federal Ministry of Education and Research (BMBF) provided sizable funding for the experiment and the scientific personnel needed to conduct it. The project includes 250 physicists from the US, Germany, Sweden, Belgium, Switzerland, Japan, Canada, New Zealand, Australia, the United Kingdom, and Korea. Professor Lutz Köpke's work group at Mainz University is part of the "Precision Physics, Fundamental Interactions and Structure of Matter" (PRISMA) Cluster of Excellence.

Publication:
M. G. Aartsen et al., IceCube Collaboration
Evidence for High-Energy Extraterrestrial Neutrinos at the IceCube Detector
Science, 21 October 2013
DOI: 10.1126/science.1242856
Images:
http://www.uni-mainz.de/bilder_presse/08_physik_etap_icecube_neutrinos_01.jpg
Artistic rendering of the IceCube detector covering one cubic kilometer. Eighty six 60-centimeter wide holes were melted into the snow surface where sensors were placed at depths of 1,450 to 2,450 meters and then frozen in place. The blue cone symbolizes Cherenkov light radiation along a particle trail. The size of the colored cone indicates how much light the sensor has registered, the rainbow colors indicate the time (earlier arrival: red, later arrival: blue).

source: IceCube/NSF

http://www.uni-mainz.de/bilder_presse/08_physik_etap_icecube_neutrinos_02.jpg
Graphic presentation of the reaction of an extremely high-energy neutrino in the IceCube Detector. The size of the colored cone indicates how much light the sensor has registered, the rainbow colors indicate the time (earlier arrival: red, later arrival: blue).

source: IceCube/NSF

http://www.uni-mainz.de/bilder_presse/08_physik_etap_icecube_neutrinos_03.jpg
View over the ice at the geographic South Pole to the above-ground measuring station for the IceCube experiment. The data from the photo sensors embedded in the ice are extracted and analyzed in computer farms. The picture comes from the dusk phase during the transition from the Antarctic winter (sun below the horizon) to the Antarctic summer (sun above the horizon).

source: Sven Lindstrom, IceCube/NSF

Further information:
Professor Dr. Lutz Köpke
Experimental Particle and Astroparticle Physics (ETAP)
Institute of Physics
Johannes Gutenberg University Mainz (JGU)
D 55099 Mainz, GERMANY
phone +49 6131 39-22894
fax +49 6131 39-25169
e-mail: koepke@uni-mainz.de
http://www.etap.physik.uni-mainz.de/index_ENG.php

Petra Giegerich | idw
Further information:
http://icecube.wisc.edu/gallery/press

More articles from Physics and Astronomy:

nachricht Long-lived storage of a photonic qubit for worldwide teleportation
12.12.2017 | Max-Planck-Institut für Quantenoptik

nachricht Telescopes team up to study giant galaxy
12.12.2017 | International Centre for Radio Astronomy Research

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Long-lived storage of a photonic qubit for worldwide teleportation

12.12.2017 | Physics and Astronomy

Multi-year submarine-canyon study challenges textbook theories about turbidity currents

12.12.2017 | Earth Sciences

Electromagnetic water cloak eliminates drag and wake

12.12.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>