Possibilities for Underground Physics in the Pyhäsalmi mine

Abstract

The Pyhasalmi mine is uniquely suited to host new generation of largescale underground experiments. It was chosen both by the LAGUNA-LBNO and by the LENA Collaboration as the preferred site for a giant neutrino observatory. Regrettably, none of these projects got funded. The termination of the underground excavations in the fall of 2019 marks an important milestone. To maintain the infrastructure in good condition a new sponsor must be found: either a large-scale scientific project or a new commercial operation. The considered alternatives for the commercial use of the mine include a pumped-storage hydroelectricity plant and a high-security underground data-storage centre. Without a new sponsor the ongoing experiments, including the cosmic-ray experiment EMMA and the study of C14 content in liquid scintillators, have to be completed within the next few years.