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IFIC, CSIC – University of Valencia, Spain University and INFN-Sezione di Padova, Italy INFN-Laboratori Nazionali di Legnaro, Padova, Italy University and INFN-Sezione di Milano, Italy Department of Physics, Texas A&M University, USA Department of Physics, Lund University, Sweden
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IFIC, CSIC – University of Valencia, Spain University and INFN-Sezione di Padova, Italy INFN-Laboratori Nazionali di Legnaro, Padova, Italy University and INFN-Sezione di Milano, Italy Department of Physics, Texas A&M University, USA Department of Physics, Lund University, Sweden IEM – CSIC Madrid, Spain University of York, York, United Kingdom CEA-Saclay, SPhN, France LRI – University of Salamanca, Spain GSI-Darmstadt, Germany and the AGATA, PRESPEC, LYCCA and FRS collaborations Coulomb excitation of the band-terminating 12+ yrast trap in 52Fe A.Gadea(IFIC Valencia) C.A.Ur(Univ. and INFN Padova) M.Gorska (GSI Contact Person)
The fp-Shell: Laboratory for Nuclear Models Comparison of LSSM and CHFB descriptions Extended experimental information + Large Scale Shell Model calculations 48Cr E.Caurier et al., PRL 75 Observation of rotational properties S. M. Lenzi et al., PRC 56 Accurate description of the nuclear excitations N=Z A. P. Zuker et al., PRL 89
The 52Fe level scheme 12+ seniority isomer & yrast trap Rotor with b=0.26 Exp. GASP@LNL +MS@GSI LSSM withKB3G K=0: (g.s.) K=6: p or n [312]5/2- [303]7/2- K=12: p and n[312]5/2- [303]7/2- C.A.Ur et al., Phys. Rev. C58 (1998) 3163 F.Brandolini and C.A.Ur, Phys. Rev. C71 (2005) 054316A.Gadea et al., Phys. Lett. B619 (2005) 88 Spin
Hint of Collectivity in the 12+ state Exp. GSI mass separator Minimum p3/2 occupancy The S.M. calculations do not reproduce the B(E4), specially the B(E4, 12+ 8+1) . “Best” agreement with the more collective 12+ calculated with FPD6 A.Gadea et al., Phys. Lett. B619 (2005) 88
M.Axiotis et al., PRC76 (2007) 014303 52Fe 52Mn Unexpected low energy negative parity states in 52Fe and 52Mn C.A.Ur et al., PRC58 (1998) 3163 Large l proton decay of the deformed states in 56Ni, 58Ni, 58Cu and the 10+ isomer in 54Ni D.Rudolph et al., PRC78 (2008) 021301(R)
fp-Shell LSSM Calculations fp-Shell LSSM calculation performed with the GXPF1 interaction and the code ANTOINE B(E2 12+2 12+1) = 21 e2fm4 B(E2 14+1 12+1) = 27 e2fm4 B(E2 14+2 12+1) = 6 e2fm4 Preliminary Beyond-Mean Field calculation suggest oblate deformation for the 12+ and 14+ states with quadrupole moments Q=-53 fm2 and -218 fm2
Experimental Details Experiment to be performed with the GSI-FRS secondary isomeric beam at the AGATA-PRESPEC setup GSI-FRS S4 Production of the 12+ isomeric beam b y fragmentation of 58Ni on a 9Be target Separation of 52Fe at FRS Coulomb excitation on a 750mg/cm2 208Pb or 197Au target Detection of gamma-rays with AGATA Identification of secondary products with LYCCA 58Ni Primary Beam Fragmentation LYCCA Light target 9Be target
Experimental Details Secondary target ~3.5 ps to cross the target: fast g-raytransition(~ 0.2ps) FWHM given by Db in target calculated to be max. 3% for AGATA 52Fe* 52Fe12+ b=0.51 b=0.48 750mg/cm2 H.J. Wollersheim et al., NIM A537 • Relativistic Coulom Excitation for the 12+ isomer calculated with the DWEIKO code (C.A.Bertulani et al.) 5mb for the LSSM B(E2) (B(E2,12+114+1)= 31 e2fm4 pessimistic value of band terminating) • Primary SIS beam 58Ni 109 ions per spill. • MOCADI and LISE++ predict 105 per spill 52Fe ions at FRS focal plane • Isomeric yield estimated ≥ 10% (example 10+ isomer in 54Ni) • g-ray energy Emitted by the ion at b=0.51 5.5 MeV • AGATAefficiency for 5.5 MeV g-ray (with Lorentz Boost) ~3% • Solid angle efficiency for LYCCA-0 in this reaction 79% • With 2 s spill 1000 counts in 15 shifts • Special requirements segmented SC detector at S2 (under construction) and digital readout at the MUSIC and TPC detectors (under development)
Collaboration: A.Gadea, A.AlgoraIFIC, CSIC – University of Valencia, Spain C.A.Ur, S.M. Lenzi, S.Lunardi, E.Farnea, D.Bazzacco, R.Menegazzo, D.Mengoni, F.Recchia University and INFN-Sezione di Padova, Italy M.Górska, P.Boutachkov, J.Gerl, S.Pietri, H.J.Wollersheim, H.Grawe, C.Domingo-Pardo, I.Kojouharov, H.Schaffner, N.Goel, R.Hoischen, T.Engel GSI-Darmstadt, Germany J.J.Valiente-Dobón, G.de Angelis, D.R.Napoli, E.Sahin, C.Michelagnoli INFN-Laboratori Nazionali di Legnaro, Padova, Italy A.Bracco, G.Benzoni, S.Brambilla, F.Camera, F.Crespi, S.Leoni, B.Million, D.Montanari, N.Blasi, O.WielandUniversity and INFN-Sezione di Milano, Italy C.A.BertulaniDepartment of Physics, Texas A&M University, USA D.Di Julio, C.Fahlander, J.Gellanki, P.Golubev, R.Hoischen, D.Rudolph Department of Physics, Lund University, Sweden A.Jungclaus IEM – CSIC Madrid, Spain M.A.BentleyUniversity of York, York, United Kingdom A.Obertelli, W.KortenCEA-Saclay, SPhN, France B.Quintana, M.Doncel, I.SagradoLRI – University of Salamanca, Spain and the PRESPEC, FRS and LYCCA collaborations