Speaker
Christopher Bauer
(Technische Universitaet Darmstadt (DE))
Description
A radioactive beam of 140Nd was impinging on a 1.40 mg/cm2 48Ti as well as a 1.55 mg/cm2 64Zn target. Gamma rays were detected by the MINIBALL array and a DSSD was used for particle identification. The transition strength of the first 2+ to the 0+ ground state in unstable, neutron-deficient 140Nd was measured to be 30(5) W.u. (preliminary). The beam was contaminated by 140Sm, this allows to determine also a limit for the transition strength in that isobar. The result for the B(E2) value in 140Nd deviates from the empirical rules for quadrupole collectivity [1,2] and the predictions of the contemporary microscopic model (QPM for N=80 predicts 17 W.u. [3] with parameters as in [4]). This unexpected behavior prompts for new, refined microscopic calculations and potentially can be related to the shell stabilization of the quadrupole isovector valence shell excitations. The result is also important for preparation of the planned HIE-ISOLDE experiment, which aims to identify the one-phonon mixed-symmetry 2+ state.
[1] L. Grodzins, Phys. Lett. 2, 88 (1962)
[2] R.F. Casten, Nucl. Phys. A443, 1 (1985)
[3] Ch. Stoyanov, private communication
[4] N. Lo Iudice, Ch. Stoyanov, D. Tarpanov, Phys. Rev. C77 (2008) 044310
Primary authors
Christopher Bauer
(Technische Universitaet Darmstadt (DE))
Georgi Ivanov Rainovski
(University of Sofia (BG))
Co-authors
Andrey Atanasov Blazhev
(Institut fur Kernphysik - Universitaet zu Koeln)
Antoaneta Damyanova
(CERN)
Christian Stahl
(Technische Universitaet Darmstadt (DE))
Esther Sabine Bönig
Joerg Leske
(TU Darmstadt)
Kalin Gladnishki
(University of Sofia (BG))
Kevin Moschner
(Universitaet zu Koeln (DE))
Marcus Scheck
(University of Liverpool)
Miroslav Danchev
(University of Sofia (BG))
Prof.
Norbert Pietralla
(IKP, Technische Universität Darmstadt)
Robert Stegmann
(Technische Universitaet Darmstadt (DE))
Thorsten Kroell
(TU Darmstadt)
Timo Bloch
(Technische Universitaet Darmstadt (DE))
Volker Ralph Werner
(Yale University (US))
