Cosmogenic Activation: Recent Results

Activation of materials is known to cause background events in underground experiments that may affect the sensitivity of these experiments to rare event searches. The most common source of activation is the exposure of materials to cosmic rays at the surface of the Earth but other various sources of neutrons may also be dangerous. Different computer codes provide estimates of production rates of radioactive isotopes due to activation but their results are sometimes inconsistent. High-sensitivity experiments looking for dark matter, neutrino-less double-beta decay or neutrinos from various sources, although affected by activation, provide crucial tests of models used in the codes. Recent calculations and measurements of activation rates are discussed in this paper.