Speaker
Mr
Mateusz Krzysiek
(IFJ PAN Kraków)
Description
Giant Resonances are collective modes of excitation of atomic nuclei, providing useful information on nuclear structure and on the effective nucleon-nucleon interaction. It is possible to excite such resonances with different probes as for example: photons, charged particles or heavy ions, followed by subsequent decays by emission of particles and γ’s. Below particle threshold, a large fraction of highly excited states has been found to be of a dipole nature and it has been associated to the Pygmy Dipole Resonance, caused by the oscillation of the neutron skin against the inert proton-neutron core.
Main aim of this study is a deeper understanding of the nuclear structure properties of the Pygmy Dipole structures in 140Ce, excited via inelastic scattering of an 17O ion beam. Comparison with previous results for this nucleus, investigated in (γ,γ') and (α,α') experiments, will be helpful for drawing final conclusions.
The experiment was performed at Laboratori Nazionali di Legnaro, Italy. Inelastic scattering of 17O projectiles at 20 MeV/A was used to excite the resonance modes in the 140Ce target (2.5 mg/cm2 thick). Gamma rays were registered by 5 AGATA triple clusters and 8 large volume scintillators (LaBr3), useful for high γ-energy. The detectors were mounted at a distance of about 20 cm from the target position, resulting in a full absorption efficiency of about 0.8% at 10 MeV. The scattered 17O ions were identified by two ΔE-E Si telescopes of the TRACE array mounted inside the scattering chamber at 9° (which is the grazing angle for the reaction) with respect to the beam axis. The telescopes consisted of 2 segmented Si-pad detectors, each made of 60 pixels (with a pixel size of 4x4 mm2) covering an active area of 20x50 mm2. The resulting solid angle for the Si telescope was about 100 msr.
During the talk, issues concerning complex data analysis will be discussed and preliminary results of the experiment will be presented.
Primary author
Mr
Mateusz Krzysiek
(IFJ PAN Kraków)
Co-authors
Prof.
Adam Maj
(IFJ PAN Kraków)
Dr
Agnese Giaz
(University and INFN Milano)
Dr
Alexander Bürger
(Department of Physics, University of Oslo, Norway)
Ana Isabel Morales Lopez
(University and INFN Milano)
Andrea Gottardo
(INFN Legnaro)
Prof.
Andreas Görgen
(Department of Physics, University of Oslo, Norway)
Dr
Andreas Wiens
(Institut fur Kernphysik der Universitat zu Koln, Germany)
Andres Gadea Raga
(University of Valencia)
Angela Bracco
(University and INFN Milano)
Dr
Ann-Cecilie Larsen
(Department of Physics, University of Oslo, Norway)
Benedicte Million
(University and INFN Milano)
Dr
Birkenbach Benedikt
(Institut fur Kernphysik der Universitat zu Koln, Germany)
Prof.
Bogdan Fornal
(IFJ PAN Kraków)
Calin Alexandru Ur
(INFN Padova)
Caterina Michelagnoli
(University and INFN Padova)
Ciro Boiano
(University and INFN Milano)
Daniel Ricardo Napoli
(INFN Legnaro)
Daniele Mengoni
(University and INFN Padova)
Mr
Diego Barrientos
(University of Salamanca (Spain))
Dino Bazzacco
(INFN Padova)
Enrico Farnea
(INFN Padova)
Dr
Fabio Celso Luigi Crespi
(INFN Milano)
Francesco Recchia
(Univ. and INFN Padova)
Franco Camera
(University and INFN Milano)
Giacomo De Angelis
(INFN Legnaro)
Giovanna Benzoni
(INFN Milano)
Mr
Herbert Hess
(IKP University of Cologne)
Dr
Jerzy Grebosz
(IFJ PAN Kraków)
Jose' Javier Valiente Dobon
(INFN Legnaro)
Dr
Katarzyna Mazurek
(IIFJ PAN Kraków)
Ms
Kerstin Geibel
(University of Cologne)
Mrs
Luna Pellegri
(University and INFN Milano)
Prof.
Magne Sveen Guttormsen
(Department of Physics, University of Oslo, Norway)
Dr
Maria Kmiecik
(IFJ PAN Kraków)
Mr
Michal Ciemala
(IFJ PAN Kraków)
Mr
Miroslaw Zieblinski
(IFJ PAN Kraków)
Dr
Męczyński Witold
(IFJ PAN, Krakow)
Nives Blasi
(University and INFN Milano)
Oliver Wieland
(University and INFN Milano)
Prof.
Peter Reiter
(IKP University of Cologne)
Dr
Piotr Bednarczyk
(IFJ PAN Kraków)
Roberto Nicolini
(University and INFN Milano)
Prof.
Santo Lunardi
(University and INFN Padova)
Sergio Brambilla
(University and INFN Milano)
Silvia Leoni
(University and INFN Milano)
Prof.
Silvia Monica Lenzi
(University and INFN Padova)
Stefano Riboldi
(University and INFN Milano)
Prof.
Sunniva Siem
(Department of Physics, University of Oslo, Norway)
Mr
Tayfun Huyuk
(IFIC (CSIC - Universidad de Valencia))
Mr
Tim Steinbach
(Institut fur Kernphysik der Universitat zu Koln, Germany)
Valeria Vandone
(University and INFN Milano)
