Centre for Underground Physics in Pyhäsalmi

Centre for Underground Physics in Pyhäsalmi or CUPP is an underground physics laboratory located in Pyhäjärvi, Finland. It is located in the deepest metal mine of Europe, the Pyhäsalmi Mine (1,444 m or 4,738 ft 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-physics and cosmic radiation, as well as other subjects (ranging outside physics, like geology or biology) that benefit from the underground laboratory's unique conditions. The reason that the laboratory is underground is because in the particle physics experiments, 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 (2012) hosting the EMMA experiment, and it's a candidate site for the proposed European LAGUNA-observatory. 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 cosmic radiation) in 2003-2005. The laboratory is managed by a regional unit of the University of Oulu, the Oulu Southern Institute, and it has seven employed personnel and hosts visiting researchers.