Speaker
Christopher Bauer
(IKP, TU Darmstadt, Schlossgartenstrasse 9, D-64289 Darmstadt, Germany)
Description
The importance of precise lifetime information has recently been demonstrated in experiments at REX-ISOLDE and MINIBALL using the sensitivity of the Coulex yields to the nuclear reorientation effect in order to determine the sign of the spectroscopic quadrupole moment of the 2+1 state in 70Se [1,2]. Therefore we have utilized a new combined technique of lifetime measurement using the Doppler-Shift-Attenuation-Method (DSAM) and analysis of Coulex yields for the measurement of the spectroscopic quadrupole moment of the 2+1 state in unstable neutron-rich 140Ba. On the basis of the new lifetime of tau = =12.5(6)ps it was possible to fix the sign of the spectroscopic quadrupole moment to be negative - equivalent to an oblate deformation. Furthermore the experiment was used to test the feasibility of ''Recoil-in-vacuum'' studies at REX-ISOLDE and MINIBALL for the measurement of magnetic dipole moments, as recently described in [3,4]. An upper limit for the absolute value of the g(2+1)-factor in 140Ba could be obtained.
[1] A. M. Hurst et al., Phys. Rev. Lett. 98, 072501 (2007)
[2] J. Ljungvall et al., Phys. Rev. Lett. 100, 102502 (2008)
[3] N. J. Stone et al., Phys. Rev. Lett. 94, 192501 (2005)
[4] A. E. Stuchberry and N. J. Stone, Phys. Rev. C 76, 034307 (2007)
Author
Christopher Bauer
(IKP, TU Darmstadt, Schlossgartenstrasse 9, D-64289 Darmstadt, Germany)
Co-authors
Joerg Leske
(IKP, TU Darmstadt, Schlossgartenstrasse 9, D-64289 Darmstadt, Germany)
Norbert Pietralla
(IKP, TU Darmstadt, Schlossgartenstrasse 9, D-64289 Darmstadt, Germany)
Thorsten Kroell
(IKP, TU Darmstadt, Schlossgartenstrasse 9, D-64289 Darmstadt, Germany)
