News

During the IDM conference in L'Aquila, Italy, the XENON collaboration announced the detection of signals produced by neutrinos coming from the Sun. These neutrinos can interact with xenon nuclei via the so-called CEvNS (coherent elastic neutrino-nucleus scattering), and thanks to the ultra-low background environment and the low-energy detection capability of XENONnT, this detection was possible.

The outcome of this analysis shows events that are compatible with signals of the scattering of solar B-8 neutrinos with xenon nuclei within a statistical uncertainty of 2.7 sigma. This means that the probability of these signals being background is around 0.35%.

Although CEvNS had already been observed before in another experiment (COHERENT, 2017), this is the first time that an experiment detects CEvNS of neutrinos from the Sun.

For more info, visit the XENON web page

The Neutrino conference was held this year in Milan from June 16 to 22. Amongst many exciting news in the world of neutrinos, our group presented several posters and a plenary talk.

Paloma Cimental, PhD student, presented a poster on two-neutrino electron capture with positron emission in the Xe-124 isotope with the XENONnT experiment (poster). Our postdocs Jose Cuenca, Diego Ramirez, and Ricardo Peres, presented posters on Cosmogenic background simulations for neutrinoless double beta decay with the DARWIN (poster), Neutrino physics with the DARWIN observatory (poster), and Real-time detection of Supernova Neutrinos in XENONnT (poster), respectively. Representing the tight link between dark matter and neutrino searches, Prof. Laura Baudis held an invited plenary talk on Neutrinos with dark matter detectors (talk).

After a great week of neutrino physics, we’re already looking forward to Neutrino 2026 at UC Irvine!

The LEGEND-200 experiment aims to search for neutrinoless double beta decay of ⁷⁶Ge. It revealed its first year of physics data in the Neutrino-2024 conference held in Milan from June 16 to 22. After unblinding, we observed a background level that is comparable to GERDA. With an accumulated 48.3 kg·yr of exposure from LEGEND-200, the combined result including its predecessors, GERDA and the Majorana Demonstrator, gives a decay half life of T_1/2 > 1.9·10²⁶ yr.  A publication to report on our first result is under preparation.     

Our group congratulates Gabriela Rodrigues Araujo for winning the CHIPP prize 2024 for the best PhD thesis in particle physics. In the award ceremony during the CHIPP meeting in Geneva, the CHIPP Prize jury honoured Gabriela for her "significant and novel contributions to a wide range of experimental techniques for the GERDA, LEGEND, MONUMENT and PALEOCCENE experiments in the field of neutrino physics". She performed this work during her PhD in our group. To know more about Gabriela and her work, check the article availabe in the CHIPP Website.

We congratulate our group member Alexander Bismark for having been awarded the UZH Postdoc Grant for early career researchers. As part of the XENON and DARWIN collaborations, he will engage in the search for signatures from spontaneous wave function collapse in XENONnT data and study the optical properties of xenon at the Xenoscope facility.