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For a few years, the medical cyclotron Proteus C-235 at the Cyclotron Centre Bronowice in Kraków, Poland has been regularly used fornuclear structure experiments. One of the ongoing studies is focused on the γ decay of collective states populated in (p,p'γ) reactions. In a recent experiment, γ decays of excited states in the energy region of the Pygmy Dipole Statesin 208Pb have been observed. Good efficiency and energy resolution provided by the PARIS clusters and LaBr3Ce scintillators facilitate a comparison of the obtained energy spectra with previous measurements of pygmy states in this nucleus. [ABSTRACT FROM AUTHOR]

A very first experiment in the field of nuclear structure at the Cyclotron Centre Bronowice (CCB) facility in Kraków, Poland has been performed recently. The medical cyclotron IBA Proteus C-235 located at CCB produces proton beams in the energy range of 70-230 MeV, that can be used for experimental purposes as well. In the reported measurement, the energy of scattered protons at the incident beam energy of 85 MeV and emitted γrays from the excited 208Pb target were measured in coincidence. During the experiment excitations in the energy region of the Giant Quadrupole and Dipole Resonances, as well as the Pygmy Dipole States were observed. By applying different conditions on the data, spectra corresponding to decays of excited states to selected low-lying levels in 208Pb were obtained, allowing a look into the Brink-Axel hypothesis. [ABSTRACT FROM AUTHOR]

The decay of the 21.47-MeV stretched resonance in 13C, arising from p 3 / 2 → d 5 / 2 nucleon excitation coupled to maximum spin, was investigated in a (p , p ′) experiment at 135 MeV proton bombarding energy, performed at the Cyclotron Centre Bronowice (CCB) at IFJ PAN in Krakow. First experimental information on the proton and neutron decay branches from this state was obtained by using coincidence measurement of protons inelastically scattered on a 13C target and γ rays from daughter nuclei, namely, 12B (proton decay) and 12C (neutron decay). The main branches lead to the J π = 2 + , first-excited state at 0.953 MeV in 12B, and to the J π = 1 + , T = 1 level at 15.110 MeV in 12C. The results were compared with predictions from the Gamow Shell Model (GSM), which was used to describe the stretched resonance in terms of its energy, width, electromagnetic transition strengths and decay pattern. A very good agreement was obtained between the measured and calculated properties of the 21.47-MeV stretched resonance in 13C, demonstrating the high-quality and precision of the GSM wave function calculations, which include coupling to the resonant and non-resonant particle continuum. [ABSTRACT FROM AUTHOR]