ROOM
88
Space Science
Finding neutrinos is no easy task. In the past it has required huge
underground liquid-filled tanks to capture the tell-tale signature of an
interaction with one of the lightest known particles known to us. Now, a new
project aimed at finding the most energetic of neutrinos is being constructed
above ground at the Ross ice-shelf in Antarctica. Known as ARIANNA
(Antarctic Ross Ice-Shelf ANtenna Neutrino Array), the project hopes to
shed light on which astronomical phenomenon is responsible for creating
relativistic particles that leave very little trace of where they came from.
Anna Nelles
University of
California, Irvine, USA
N
eutrinos are neutral subatomic particles
with a mass close to zero and,
experimentally, they were only discovered
in the 1950s. Detecting neutrinos is a
difficult challenge as being one of the lightest
known particles, large quantities of matter are
needed to observe them as the neutrino
interaction cross-section i.e. the probability to see
them interact, is very small per unit of matter.
When you think of neutrino experiments, huge
tanks filled with water or other liquids spring to
mind, which are not only pretty to look at but are
also impressively large. However, this in itself poses
a problem and when laboratory experiments could
no longer be made bigger due to practicality and
cost-restrictions, scientists turned to naturally
occurring materials instead. Now, experiments
designed to search for neutrinos can be found in
locations such as the Mediterranean Sea, in lake
Baikal in Russia and in the ice of Antarctica.
If you ever wondered why an increasing mass
volume is so important for finding neutrinos, when
they have already been detected in laboratory
experiments, it is because scientists are not only
Hunting for neutrinos
in the ice of Antarctica
