Bonner Sphere Spectrometer at the Environmental Research Station Schneefernerhaus: Measuring Cosmic Radiation and Facilitating Data Accessibility

In 2024, Germany’s national metrology institute, the Physikalisch-Technischne Bundesanstalt (PTB), signed a sponsorship agreement with the Operational Company of the Environmental Research Station Schneefernerhaus (Umweltforschungsstation, UFS) for the operation, maintenance and upgrade of the Bonner sphere-based neutron spectrometer located at the UFS. The UFS Schneefernerhaus was established in 1999 and is Germany’s highest research station at an altitude of 2650 meters, just below the summit of Mt. Zugspitze, where it houses a wide range of scientific instruments for observing weather, climate and climate change.

The Bonner Sphere Spectrometer (BSS) system at the UFS Schneefernerhaus has been in operation since 2005, thanks to the cooperation between the UFS Operational Company and the German Research Center for Environmental Health of the Helmholtz Center Munich. The system is used for continuous measurements of the neutron component of secondary cosmic radiation. With an extensive set of polyethylene sphere moderators and spheres with metal shells, the BSS at Schneefernerhaus can detect neutrons with energies ranging from 10^-9 MeV to 10³ MeV. Thanks to its spectrometric capabilities, the system can provide neutron energy spectra, which is an advantage over the classical neutron monitors used worldwide.

The Neutron Radiation Department of PTB is currently working on upgrading the data acquisition hardware and software, data storage, workflow and data analysis of the BSS system towards an automated and robust operation.

This presentation introduces methods for error correction and data preparation, incorporating historical data (years 2013 to 2024) from the former team of the Helmholtz Center Munich, and discusses possibilities for disseminating the data to scientific communities.