ーRCNP SEMINARー


Date & Time : 12/7 (Thu.) 16:00 - 17:00

Place : Lecture room, 4th floor

Speaker : Dr. Lucia-Ana Popescu (KVI, Groningen University)

Title : Neutrino-less double-beta decay studies

Abstract :

The last decade has seen tremendous efforts to reveal the physics of neutrinos.
The recent evidence that neutrinos are massive is a first hint for physics beyond the Standard Model of particle physics.　Nevertheless, several fundamental questions remain unanswered: What is the absolute mass scale and the mass hierarchy of　neutrinos, and, perhaps most intriguingly, is the neutrino its own antiparticle? The only feasible way to answer both questions is to detect a nuclear decay process where a nucleus of mass A and charge Z decays into a nucleus of the same mass A, but Z changed by two units without emission of neutrinos: neutrino-less double-beta decay (0ν2β). Major experiments in preparation world-wide to detect 0ν2β have gained urgency by the highly controversial recent claim of the observation of 0ν2β in 76Ge. However, theoretical studies show that the accurancy with which the nuclear structure involved is known poses a critical limitation for the interpretation of eventually measured decay rates. This imposes measurements of high-resolution nuclear charge-exchange reactions, i.e.reactions where a neutron is exchanged with a proton or vice versa, for the nuclei under consideration for future decay experiments. Subsequent measurements of both reactions are the most selective and direct method to get spectroscopic information on the complete set of nuclear transmissions involved in the double-beta decay. This will provide the required calibration of the theoretical calculations. Along this line I will present data obtained in recent years at KVI and collaborating institutes.


Contact Person : H. Okamura