Speaker
Description
Atomic nuclei exhibit fundamental collective vibrational modes, such as Giant Resonances (GR) and Pygmy Dipole Resonances (PDR), which provide insights into many-body nuclear dynamics, the nuclear equation of state, and astrophysical processes. In recent years, the proton facility at the Cyclotron Centre Bronowice (CCB) of the Henryk Niewodniczański Institute of Nuclear Physics PAN in Kraków has emerged as active center for investigating these phenomena using fast proton beams with energy ranging from 70 to 230 MeV.
This presentation provides an overview of the research program on collective excitation modes carried out at CCB via inelastic proton scattering. The experimental setup combines the KRATTA triple-telescope array for scattered proton identification and excitation energy (E) determination with high-efficiency scintillation arrays including PARIS clusters and large-volume LaBr$_3$:Ce detectors for high-energy γ-ray spectrometry. Coincidence measurements of E vs. Eγ allow for precise determination of specific decay channels.
The main focus of this contribution will be dedicated to the recent investigation of the Isoscalar Giant Quadrupole Resonance (ISGQR) and Giant Dipole Resonance (GDR) in $^{120}$Sn using a 200 MeV proton beam. Experimental data on the γ-decay of the ISGQR are extremely scarce due to strong competition from the dominant neutron emission channel, and they exist only for $^{208}$Pb up to now. In addition, to highlight the broader context of the research program at CCB, other studies will be briefly mentioned, including the γ-decay of the GQR in $^{208}$Pb and PDR in Ni isotopes.