My research activity started in 1994 when I had my master's degree. It concerns Neutrinos, Gamma rays and Cosmic Rays, which in one word we can define as the multi-messengers of the non-thermal universe. Initially in my career, I have been working on atmospheric neutrino oscillations, simulations of neutrino fluxes in the atmosphere with FLUKA, dark matter and neutrino astronomy in the MACRO experiment at Gran Sasso. We found out that the atmospheric neutrinos we detected between millions of muons were oscillating more strongly in the vertical upgoing direction than in the horizon due to the longer baseline in the earth. For this, I was awarded the Duggal Award.

I continued to work on Neutrino Astronomy in the ANTARES undersea telescope since 1999 and in the NEMO.RD experiment of INFN, which then became KM3NeT. In ANTARES, I coordinated for 8 years the working group on astrophysics and exotic phenomena, the main analysis working group of ANTARES. In 2005 I left the continent for an adventure in the USA, which lasted 8 years. I joined the Faculty of the University of Wisconsin as an Assistant Professor and became a tenured Associate in 2007. I worked in IceCube, the first kilometre-cube neutrino telescope ever achieved, located at the South Pole, where I went during a construction season to commission strings and I happened to help deploy some. I mostly concentrated on defining the analysis for searches of time-dependent and independent point and extended sources defining a new method based on likelihood analysis, when the collaboration mostly used binned methods to search around sources. With this method, we found significant indications of signals from the blazar TXS 0506+056 and the starburst galaxy NGC 1068. In 2007 I started work on gamma-ray astronomy and hardware activities in HAWC on the trigger and photosensors (namely SiPMs). I regretfully left HAWC when I went from the USA to Geneva, joining the faculty as a full professor. I continued the activities on gammas in CTAO and became the Swiss Coordinator. My work was fundamental in establishing CTA in the Swiss Roadmap for large research Infrastructures of the State Secretariat for Education, Research and Innovation (SERI). I lead one of the projects for the construction of the small-size telescopes of CTAO, named SST-1M, and now my group works in the Large Size Telescope and is responsible of the Calibration Pipeline of DPPS software of CTAO. Also, QualityPipeline is our responsibility. I conceived and designed the SST-1M, and in a team with Polish and Czech Institutions, we built and installed two SST-1M. They are now being commissioned in the Ondroyev Observatory for a future destination. The construction of SST-1M was an extremely relevant learning experience. The results have influenced the design of the Cherenkov telescope of the Chinese Observatory LHAASO, which I joined for some years leaving it during the Ukraine war. We also produced the telescope lightguides in Switzerland for the Chinese groups. LHAASO is now performing for the first time ultra-high energy astronomy. We also published papers on SiPM properties and worked with many producers to improve the technology, and I am a WP coordinator in a proposal to the INFRA-TECH M2-Tech. In 2021, I joined a new enterprise called NUSES. I am responsible for the construction of the camera plane of photosensors of the payload TERZINA, a prototype for Cherenkov detection from space and my group leads the simulation effort.

I teach at the undergraduate and graduate student levels. Our group offers plenty of Ph.D. and Master Thesis opportunities of work. I was the Chair of APPEC Consortium between 2019-2020 and led the astroparticle community through the update of the European Particle Physics strategy. I am the President since Sep. 2023 of the Swiss Physical Society and was vice-President since Sep. 2022.

I am an evaluator of many projects, for the ERC, PRIN, Norwegian Council, SNF, NSF, DFG, clusters of excellence in Germany, Nikhef laboratory and I have been in many Scientific Committees including the Laboratori of Gran Sasso Comitato Scientifico. I refereed many papers for many journals and I am editor of Scientific Reports of Nature.

Full CV and Publication list

Publication search from Inspire, CiteSummary with three renowned papers (500+): Discovery of Cosmic neutrinos in IceCube and respective Science paper, discovery of atmospheric neutrino oscillations in MACRO.

See ORCID 0000-0001-5014-2152

Matthieu made his Ph.D. at the laboratoire de L’accélérateur linéaire in Orsay on the measurement of the proton-proton total cross section and absolute luminosity with the ATLAS/ALFA detector. He continued this activity as a Marie Curie Fellow at CERN where he also worked on detector development for medical imaging (AX-PET) in the Detector and Technology group.
He joined the CTAO group at the university in 2014 and acted as the coordinator for the Cherenkov camera realisation. He is now managing the CTAO activities within the group and act as a deputy System Engineer for the large size telescope of CTAO. Matthieu is the leader of the Advanced SiPM camera WG in the Large Size Telescope project of CTAO.

Luca joined the group in June 2022 as electronic engineer in the FLARE project to build Advanced Cameras for Large Size gamma-ray Telescopes. In particular his task is to design and to realize an ASIC for preamplify and shape the signal of large size SiPMs.