News

Our group was well represented at the LIght Detection In Noble Element (LIDINE) conference, held in Nikhef, Amsterdam, 6-9 October 2026. The conference provided an important opportunity to exchange knowledge and discuss advances in detector technologies based on noble elements and their wide range of applications in physics, including dark matter, neutrino detection, neutrinoless double beta decay, coherent elastic neutrino-nucleus scattering.

We presented three contributions: Recent results and current status of the XENONnT Dark Matter experiment by  Luisa Hötzsch, R&D on candidate wavelength-shifting reflectors for the LEGEND-1000 liquid argon instrumentation by Gloria Senatore and Recent results and future plans of Xenoscope TPC by Florian Jörg.

Beyond the scientific presentations, the conference was a valuable opportunity to network, establish new collaborations, strengthen existing ones, and exchange ideas on experiments involving noble liquids.

The 10th edition of the Low Radioactivity Techniques (LRT2026) workshop took place in York, UK, from 21-24 September 2026. The workshop offered a broad overview of current developments in low-background physics experiments and the technologies supporting them, with contributions addressing the identification and mitigation of radioactive backgrounds, material screening, and improvements in radiopurity assessment techniques. These topics are particularly relevant to next-generation rare-event searches, where controlling background contributions is essential to achieving the required experimental sensitivity.

Our group presented the following contributions:  1500 Meters Beneath the Alps: Toward a Swiss Low-Background Laboratory in the Bedretto Tunnel by Florian Jörg, Results of the LEGEND-200 background mitigation campaign  by Sofia Calgaro, Testing radon mitigating surface coatings in Xenoscope - a 2.6 meter long liquid xenon TPC by Margherita Noia and Gator: A low-background Germanium facility for high sensitivity gamma-ray spectroscopy  by Aravind Sreekala.

Congratulations to our summer student Tim Van de Vendel for receiving one of the three Best Presentation Awards at the CHIPP Summer Student Program 2026 (S3P3)!

Tim succesfully completed his two-month research project about the optical characterization of wavelength-shifting reflective materials in study to be employed in the liquid argon veto of the next-phase neutrinoless double beta decay experiment LEGEND-1000. Being the signal searched for very rare, efficient liquid argon scintillation light wavelength-shifter and reflective materials, together with a precise knowledge of their optical response, are of key importance. Tim contributed towards this important goal by operating the liquid argon setup, LArS, available at UZH, sensitive to different material light yields.

One of the other two awards was received by another UZH summer student, Zhoie Tan Lamanero, who studied quantum entanglement in Z → μ+ μ- at the CMS experiment in the group led by Ben Kilminster.
Congratulations to both Tim and Zhoie for their outstanding achievement!

The XENONnT experiment has recently achieved a new milestone in the study of solar neutrinos, observing neutrino–electron interactions at energies as low as 17keV with a significance of 5 sigma. The experiment's ultra-low background and low energy threshold allow it to detect these rare neutrino interactions, extending the accessible energy range by more than an order of magnitude compared to previous experiments (arXiv preprint). Solar neutrinos are produced by the nuclear fusion processes that power the Sun and provide a unique window into its core. This result demonstrates the potential of liquid-xenon detectors as multipurpose observatories, opening a new window into low-energy neutrino physics. Got curious? Please make sure to also have a look at the in-depth article on our UZH News page.

A potential site for a Swiss deep underground laboratory is currently being explored in the Bedretto Tunnel beneath the Gotthard massif in the canton of Ticino. Located 3.5 km from the tunnel entrance, the site lies beneath up to 1500 metres of rock. This natural shielding makes it an exceptional location for experiments that require an environment almost entirely free from interference caused by cosmic radiation.

The results of a comprehensive campaign to characterize the underground environment in the Bedretto tunnel have now beenpublished in European Physics Journal C. The study, which was carried out in close collaboration with the BedrettoLab group at the ETH Zürich, confirms the site's remarkable potential. In particular, the measured flux of cosmic muons is found to be reduced by a factor of one million inside the cavern. This would make the Bedretto Tunnel the second deepest underground laboratory site in Europe.