Institute of Physics
Topic
Lifetime Measurements of Neutron-Rich Isotopes Near the N=126 Closed Shell Using AGATA and PRISMA
PhD. program
Nuclear and subnuclear physics
Year of admission
2025
Name of the supervisor
Mgr. Andrej Herzáň, PhD.
Contact:
Receiving school
Faculty of Mathematics, Physics and Informatics
Annotation
Experiment 22.76 was performed at LNL INFN in Legnaro, Italy, with the goal of studying transition probabilities of low-lying excited states in isotopes near the N = 126 closed shell through lifetime measurements. These states were populated via a multi-nucleon transfer reaction, where a 136Xe beam impinged on a self-supporting 198Pt target, resulting in data collection for a wide range of W–Pb isotopes. Gamma rays were detected using AGATA, one of the most advanced gamma-ray tracking detector arrays in the world, coupled with the PRISMA large-acceptance magnetic spectrometer for complete identification of beam-like ions. Both spectrometers were positioned based on the grazing angle of the reaction. A dedicated plunger device, used in a reversed configuration, was employed for lifetime measurements. A Nb foil acted as the stopper/degrader, stopping target-like particles and allowing for the observation of the ratio between stopped and in-flight emitted gamma rays. Due to the complexity of this modern experimental setup, data analysis is particularly challenging, and the results are frequently compared with dedicated simulations.