Subscribe free to our newsletters via your
. 24/7 Space News .

Detector at the South Pole explores the mysterious neutrinos
by Staff Writers
Copenhagen, Denmark (SPX) Apr 22, 2015

Jason Koskinen is shown at the South Pole. In the background is the IceCube Lab. All data from the instruments deep down in the ice comes up through the two "towers" and into the computer center, where the first analyses are done. Image courtesy T. Waldemaier. For a larger version of this image please go here.

Neutrinos are a type of particle that pass through just about everything in their path from even the most distant regions of the universe. The Earth is constantly bombarded by billions of neutrinos, which zip right through the entire globe, houses, animals, people - everything.

Only very rarely do they react with matter, but the giant IceCube experiment at the South Pole can detect when there is a collision between neutrinos and atoms in the ice using a network of detectors.

New research results from the Niels Bohr Institute among others have measured the neutrinos at the South Pole and have calculated some of the physical properties of the otherwise exotic and poorly understood particles. The results are published in the scientific journal Physical Review D.

Neutrinos are among nature's most abundant particles. Their number far exceeds the number of atoms in the entire universe - yet we know little about them. Neutrinos are a type of particle created in the Big Bang and are also produced in the Sun's interior and in violent events like supernovae, which are exploding stars. Neutrinos are also called 'ghost particles' because they basically do not interact with matter, but pass undisturbed through everything in their path.

Instruments at the South Pole
Researchers from 44 institutions in 12 countries are part of an international project, IceCube at the South Pole to study the mysterious particles with the strange properties.

IceCube is an enormous particle detector located deep in the ice at the South Pole. The instruments in the detector are comprised of 86 cables each with 60 digital Optical Modules (extremely sensitive light sensors). Each cable is lowered down into a hole, which is melted through the 2 0.5 km ice sheer using a hot water drill. The detector is located deep below the surface - it starts 1 0.5 km below the ice and ends at the bottom at a depth of 2 0.5 km.

The detector's enormous size of a cubic kilometer is necessary because neutrinos interact extremely weakly with matter, so it is only rarely that they collide with the atoms in the ice. When they finally collide, charged particles are created, which emit radiation that can be detected by the extremely sensitive Digital Optical Modules.

"In the Ice Cube project we have registered about 35 neutrinos, which are very likely to have come distant regions in space. They have a very high energy and because they have not interacted during their long journey, they can carry information from the most distant parts of the universe. In addition to the rare cosmic neutrinos, we are also studying the neutrinos created in the Earth's atmosphere in order to unravel the physical properties of neutrinos," says Jason Koskinen, Assistant Professor and head of the IceCube Group at the Niels Bohr Institute, University of Copenhagen.

From the North Pole to the South Pole
When particles (protons) with high energy - from violent events in the cosmos like supernovae and quasars hit the Earth's atmosphere, a burst of neutrinos is formed, which passes through the Earth. The neutrinos formed over the North Pole pass straight through the Earth and very small proportion of them hit the ice at the South Pole, where the IceCube detector registers the collisions.

Neutrinos are very light particles and for many years it was believed that they were completely massless. It is now believed that there are three types of neutrinos (electron, muon and tau neutrinos), each with their specific mass, which is incredibly small - less than a millionth of the mass of an electron.

"The neutrinos created in the atmosphere over the North Pole are mostly muon neutrinos. On their way through the Earth's 13,000 km, the muon neutrinos undergo quantum fluctuations that can change them into another type of neutrino, tau neutrinos, before they are finally detected by IceCube on the other side of the globe. We can now study these effects in much greater detail than before and in this way we can gain new insights into their physical characteristics," explains Jason Koskinen.

Atmospheric neutrinos
The research group has now studied atmospheric neutrinos in the IceCube detector at the South Pole for three years and have analysed 5,200 interactions between atmospheric neutrinos and atoms in the ice.

"We have confirmed that neutrinos undergo fluctuations - even at high energy levels and we have calculated how much they exhibit these oscillations. In this study, we have only measured muon neutrinos and in comparison to how many muon neutrinos form in in the atmosphere and pass through the Earth, we only see a fraction at the South Pole.

"The explanation is that the muon neutrinos undergo quantum fluctuations that change them into tau neutrinos and we do not see those. If they had not changed, we would see them all. Our calculations show that 20 percent have undergone quantum fluctuations and changed from muon neutrinos to another type of neutrino as they pass through the Earth," explains Jason Koskinen.

Messengers from the universe
And then what, you might ask? "Because we basically want to learn more about these strange particles that are everywhere in the universe and whose properties we still do not fully understand. Because neutrinos come from the cosmos, we could use them for astronomical observations and gain new insights into the structure of the universe," says Jason Koskinen.


Related Links
University of Copenhagen - Niels Bohr Institute
Understanding Time and Space

Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks DiggDigg RedditReddit GoogleGoogle

Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News

What Big Bang? Universe May Have Had No Beginning at All
Moscow, Russia (Sputnik) Mar 02, 2015
What we don't know about the Universe... could fill the Universe. Two theoretical physicists have suggested nothing like the Big Bang played a role in the start of our universe 13.8 billion years ago, refuting Edwin Hubble's 1929 theory that the universe was contained in a single point in space and some violent event caused it to expand. "Our theory suggests that the age of the universe co ... read more

Yutu finds Moon still active in old age

Japan planning moon mission: space agency

Manned Moon Flight Planned For 2030

A new view of the moon's formation

Robotic Arm Gets Busy on Rock Outcrop

Mars might have liquid water

NASA's Curiosity Rover Making Tracks and Observations

NASA Mars Rover's Weather Data Bolster Case for Brine

Space icon reflects on origins of space program

Russia vows to put Russian cosmonauts on Moon no later than 2030

Ramping Up For Johnson's Chamber A Test

NASA Offers Study Volunteers Big Bucks to Stay in Bed

Chinese scientists mull power station in space

China completes second test on new carrier rocket's power system

China's Yutu rover reveals Moon's "complex" geological history

China's Space Laboratory Still Cloaked

Sixth SpaceX Delivery of Station Research With a Side of Caffeine

Research for One-Year Space Station Mission Launched On Falcon 9

Astronaut Hadfield to release first space album

Special 3-D delivery from space to Marshall Space Flight Center

SpaceX Dragon cargo ship arrives at space station

Video shows SpaceX rocket booster crash land on floating target

Russia Should Consider Launching Super-Heavy Rockets From Vostochny

Rocket tips over after SpaceX recycle attempt

Spitzer, OGLE spot planet deep within our galaxy

An exoplanet with an infernal atmosphere

Spitzer Spots Planet Deep Within Our Galaxy

Hot and Stormy at High Altitudes on Exoplanet HD 189733b

Disney develops layered fabric 3-D printer

Honeywell gives European Space Agency new satellite technology

ADS NEWTON products enable agile satellite missions

IBM earnings dip as sales fall again

The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.