Lifetime measurements of excited states in neutron-rich ⁵³Ti: benchmarking effective shell-model interactions

Level lifetimes of the yrast (5/2⁻) to 13/2⁻ states in the neutron-rich nucleus ⁵³Ti, produced in a multinucleon-transfer reaction, have been measured for the first time. The recoil distance Doppler-shift method was employed and lifetimes of the excited states were extracted by a lineshape analysis aided by Geant4-based Monte-Carlo simulations. The experiment was performed at the Grand Accélérateur National d’Ions Lourds facility in Caen, France, by using the Advanced Gamma Tracking Array for the γ-ray detection coupled to the large-acceptance variable mode spectrometer for an event-by-event particle identification and the Cologne plunger for deep-inelastic reactions. Reduced transition probabilities, deduced from the lifetimes, give new information on the nuclear structure of ⁵³Ti, and are used to benchmark different shell-model calculations using established interactions in the fp shell