FPU2023-Understanding the antineutrino spectrum from reactors

Nuclear reactors are the largest manmade pacific sources of neutrinos. Understanding the antineutrino spectrum from reactors is of great interest for fundamental applications like the study of neutrino oscillation phenomena and for possible applications of reactor monitoring for non-proliferation of nuclear weapons. In recent years, our group has provided nuclear data that has improved considerably the description of the antineutrino spectrum from reactors using the summation method [1], but many questions remain unanswered. The role of first forbidden beta decays and what kind of shape corrections are needed for reactor antineutrino summation calculations were considered a possible explanation of the reactor anomaly and have attracted considerable attention in recent years [2]. Our group has developed a setup, the eShape setup, to measure the shape of the most relevant beta decays employing radioactive beams of very high purity (trap assisted spectroscopy). These measurements are considered of very high priority by many experts of the field. The student will analyze data from a recent experiment performed in Jyväskylä using this setup in which the beta decays of the most relevant contributors to the reactor antineutrino where measured. The student will gain considerable proficiency in data analysis using ROOT and simulations using GEANT4 and will participate in the experimental activities of the group performed in large scale facilities around the World.