Astroparticle physics experiments search for very rare processes induced by neutrinos or hypothetical dark matter particles. Such rare events can be mimicked by radioactive decays induced by natural environmental radioactivity. This a huge challenge; traces of natural radioactivity are literally “everywhere”!

In the Heidelberg Radiation Detection (H-RD) labs, we develop tools and methods to identify tiny traces of radioactivity. Our focus is on gamma-ray spectroscopy and radioactive noble gases. Gamma-ray spectroscopy with ultralow background high purity Germanium detectors offer a powerful and non-destructive tool for material screening. Our pioneering GeMPI spectrometers, developed at MPIK and operated in the Italian Gran Sasso underground laboratories, are still the world’s most sensitive instruments.

Radioactive noble gases like Rn-222 or Kr-85 are a particular hazard for astroparticle physics experiments, because noble gases are inert and easily diffuse inside detectors. MPIK has a long history in noble gas trace analysis. Our dedicated mass spectrometers and gaseous radiation detectors offer few atom sensitivity and are indispensable tools for achieving ultra-low background environment. In addition to state-of-the-art analytics, we also develop methods to actively suppress radioactivity, such as special surface coating techniques.