Centre for Underground Physics in Pyhäsalmi or CUPP is an underground

physics Physics is the scientific study of matter, its Elementary particle, fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge whi ...

laboratory located in

Pyhäjärvi Pyhäjärvi (1993–1995 ''Pyhäsalmi'') is a town and municipality in the south of Northern Ostrobothnia region, Finland. Pyhäjärvi also borders the Northern Savonia and Central Finland regions. The town belongs to the subregion of Nivala–H ...

Finland Finland, officially the Republic of Finland, is a Nordic country in Northern Europe. It borders Sweden to the northwest, Norway to the north, and Russia to the east, with the Gulf of Bothnia to the west and the Gulf of Finland to the south, ...

. It occupies part of the CallioLab research and development laboratories, overseen by Callio Pyhäsalmi. It is located in the deepest base metal mine of

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

, the

Pyhäsalmi Mine Pyhäsalmi Mine is the deepest base metal mine in Europe,Geological ...

( deep; the laboratory has sites at many levels of the mine) and uses some of the infrastructure of the mine. The laboratory is made to study

neutrino A neutrino ( ; denoted by the Greek letter ) is an elementary particle that interacts via the weak interaction and gravity. The neutrino is so named because it is electrically neutral and because its rest mass is so small ('' -ino'') that i ...

-physics and

cosmic radiation Cosmic rays or astroparticles are high-energy particles or clusters of particles (primarily represented by protons or atomic nuclei) that move through space at nearly the speed of light. They originate from the Sun, from outside of the Sol ...

, as well as other subjects (ranging outside physics, like

geology Geology (). is a branch of natural science concerned with the Earth and other astronomical objects, the rocks of which they are composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth ...

biology Biology is the scientific study of life and living organisms. It is a broad natural science that encompasses a wide range of fields and unifying principles that explain the structure, function, growth, History of life, origin, evolution, and ...

) that benefit from the underground laboratory's unique conditions. The reason that the laboratory is underground is because in the

particle detector In experimental and applied particle physics, nuclear physics, and nuclear engineering, a particle detector, also known as a radiation detector, is a device used to detect, track, and/or identify ionizing elementary particle, particles, such as t ...

s, the background radiation is a problem, which can be solved by placing the laboratory underground so that the background radiation is absorbed in the rock above. The centre is currently (2018) hosting the EMMA experiment and the C14 experiment. It was a candidate site for the proposed

an LAGUNA-observatory. As of 2018, it appears the LAGUNA-observatory will not be built anywhere in the world due to neutrino research community's attention shifting to USA

DUNE A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, flat ...

-project. The C14 experiment is a collaboration between Universities of Oulu and

Jyväskylä Jyväskylä () is a city in Finland and the regional capital of Central Finland. It is located in the Finnish Lakeland. The population of Jyväskylä is approximately , while the Jyväskylä sub-region, sub-region has a population of approximately ...

and the

Russian Academy of Sciences The Russian Academy of Sciences (RAS; ''Rossíyskaya akadémiya naúk'') consists of the national academy of Russia; a network of scientific research institutes from across the Russian Federation; and additional scientific and social units such ...

. It studies the radioactive purity of scintillator liquids (which are hydrocarbon compounds), in particular the activity of C14-isotope in those liquids. It is normally assumed that due to the large age of the hydrocarbons in scintillator liquids the C14-activity (C14 half-life is almost 6000 years) should be very low; however, experiment has found that the C14-radioactivity in scintillator liquids is typically substantially larger than normally thought. The C14 experiment is situated at 1430 meters depth. The apparatus consists of the scintillator sample (1.6 liters), two light guides and photomultiplier tubes enclosed in a radiation shield. Previous experiments hosted include the cosmic-ray experiment MUG (studying the depth dependency and time-dependence of the radiation) in 2001-2003 and MUD (studying the depth-dependency of the muon flux from

) in 2003–2005. The laboratory is managed by a regional unit of the

University of Oulu The University of Oulu () is one of the largest universities in Finland, located in the city of Oulu. It was founded on July 8, 1958. The university has around 14,200 students and 3,800 staff. 21 International Master's Programmes are offer ...

, the Oulu Southern Institute, and it has seven employed personnel and hosts visiting researchers.

EMMA

EMMA (Experiment with MultiMuon Array) is a cosmic-ray experiment taking place in CUPP and it is still partly under construction. The experiment is a joint venture of the

University of Jyväskylä A university () is an institution of tertiary education and research which awards academic degrees in several academic disciplines. ''University'' is derived from the Latin phrase , which roughly means "community of teachers and scholars". U ...

, University of Aarhus and the

. EMMA is focused on studying the composition of cosmic rays in the energy above 1 PeV-range, the so-called knee region. When a primary cosmic particle collides with the atmosphere, it decays into secondary cosmic particles creating an air shower (muons, electrons, hadrons). The rock above the experiment filters out other particles than high-energy (greater than 45 GeV) muons. EMMA is able to determine the muon shower multiplicity, lateral distribution and direction of entry-measurements. The measurements are performed at the depth of 80 metres in Pyhäsalmi mine. Measurement devices consist of nine detector stations (15 m² each) and the main part of the detectable area is covered with

drift chamber A wire chamber or multi-wire proportional chamber is a type of proportional counter that detects charged particles and photons and can give positional information on their trajectory, by tracking the trails of gaseous ionization. was located via ...

s.P. Kuusiniemi ''et al.''
Underground multi-muon experiment EMMA
(2011) ''Astrophysics and Space Sciences Transactions'', vol. 7, no. 2, Apr 2011, pp. 93–96 The drift chambers used in the experiment originate from the

DELPHI Delphi (; ), in legend previously called Pytho (Πυθώ), was an ancient sacred precinct and the seat of Pythia, the major oracle who was consulted about important decisions throughout the ancient Classical antiquity, classical world. The A ...

-experiment at

CERN The European Organization for Nuclear Research, known as CERN (; ; ), is an intergovernmental organization that operates the largest particle physics laboratory in the world. Established in 1954, it is based in Meyrin, western suburb of Gene ...

. Additionally the limited streamer tubes and plastic scintillation detectors are part of the measurement stations.

External links

Centre for Underground Physics in Pyhäsalmi

CallioLab

References

{{DEFAULTSORT:Centre for Underground Physics in Pyhasalmi Pyhäjärvi University of Oulu Particle physics facilities Underground laboratories Laboratories in Finland