Belgian Polar Platform - Research - The research projects

Non-belspo (2002-2006)

Amanda/IceCube neutrinos telescopes

Begin date: Amanda1993 (1999 for Belgium)
End date IceCube: 2015

Project description

The basic discovery tools for astronomy and astrophysics have up to now used electromagnetic waves and visible light in particular to study galactic and extragalactic phenomena. Since last decade new ideas have been proposed and tested to open a new window on the universe: use an elementary particle called “neutrino” * as a new messenger from the most violent astrophysical sources. High energy neutrinos are produced abundantly in cataclysmic* phenomena like active galactic nuclei (AGN) but are also a powerful tool to hunt for the dark matter in the universe.

Due to their very weak interaction rate with matter they travel in straight uninterrupted line from the most distant sources but need very large volume devices to detect the electrons and muons* produced when they interact. A neutrino telescope must be huge, transparent, dark, and as far as possible below the surface to shield it from cosmic rays. To overcome this challenge, neutrino astrophysicists exploit the deep oceans or the 3000-meter-thick Antarctic ice cap. The international group (see back page) of AMANDA scientists is using this Antarctic ice, which they consider an ideal medium for detecting neutrinos: it is exceptionally clear, and almost completely free of radioactivity. Light from passing muons can travel hundreds of meters through the ice, and 1500 meters below the surface, the ice is otherwise completely dark. Surprisingly enough, despite its remoteness, Antarctica is also a much more accessible place to build a neutrino telescope than the deep ocean. Operating from the U.S. South Pole Station, detectors can be deployed from a solid ice surface rather than from a ship. Also the detectors can be connected directly to a control room on the ice surface, rather than relying on submarines operating on the ocean floor to establish the connections to shore stations miles away. These advantages certainly outweigh the relative remoteness of the site.

About 700 very sensitive photomultipliers have been buried in the Antarctica ice at the South Pole Amundsen-Scott US station at a depth between 1000 and 2400 m. This detector called Amanda was build between 1993 and 2000 and is still taking data. The construction of a bigger detector, called IceCube, with a volume close from 1 cubic kilometre and equipped with 4800 photomultipliers (between -1400 and -2400 m), started in 2005 and should be completed in 2011. Only a very large collaboration of about 30 international groups (but mostly US) could handle such an ambitious and expensive project.

Belgian high energy physics teams have been involved in this project since 1999. Each year, during austral summer, Belgian physicists are travelling (with the help of US logistics) to the South Pole station, to participate to the maintenance and upgrading of those two detectors. Data are analysed in the participating university and the belgian teams are bringing a very significant scientific contribution to this new and original approach of astrophysics. Those teams are funded by the FNRS (Fonds National de la Recherche Scientifique), the FWO (Fonds voor wetenschappelijk onderzoek) and an IAP (Interuniversity attraction poles) from the Federal Science Policy.

cataclysme: violent cosmic event, such as black holes, supernovas, Big Bang
neutrino: extremely small, virtually massless subatomic particles born of nuclear reactions. Once born from a violent cosmic event, neutrinos travel at the speed of light and do not stop. They only very rarely interact with other particles, allowing them to move in a straight line to the edge of the Universe. Trillions of neutrinos reach the Earth every nanosecond and, for astrophysicists, every one of these tiny particles is a potential messenger carrying information from its source of origin.
muon: a high energy neutrino occasionally collide with a molecule. The collision breaks the nucleus apart and the neutrino converts into a muon. A muon can be recognised and reconstructed from the cone of blue light that follows it.

Complementary resources about this scientific project

Project team

Project Coordinator: Francis Halzen
University of Wisconsin - Madison

Involved Belgian research groups:

Partner 1: Professor Philippe Herquet
Université de Mons-Hainaut
Physique des Particules Elémentaires
Faculty of Sciences
Université de Mons-Hainaut
Bâtiment 4
19 Avenue Maistriau
B-7000 Mons
Belgium
Phone: +32-65-373387 or 373386
Fax: +32-65-373386

Partner 2: Professor Daniel Bertrand
Université Libre de Bruxelles
IIHE (Inter-university for high energy, IIHE);
Faculté des Sciences - CP230
Boulevard du Triomphe
B-1050 Bruxelles
Phone : +32-2-6293202
w3.iihe.ac.be

Partner 3: Professor Catherine De Clercq
Vrije Universiteit Brussel
IIHE-ELEM - Faculteit der Wetenschappen
Pleinlaan 2
B-1050 Brussel
Phone: +32-2-6293203

Partner 4: Professor Dirck Ryckbosch
Universiteit Gent
Department of Subatomic and radiation physics (WE05)
Proeftuinstraat 86
B-9000 Gent
Phone: +32-9-2646543
Fax: +32-9-2646697
ssf.rug.ac.be

+ 25 more teams in the USA, UK, Netherland, Germany, Sweden, Japan, New Zealand