Recoil distance method lifetime measurement of the 2(1)(+) state in Sr-94 and implications for the structure of neutron-rich Sr isotopes

Publication Type
Journal Article
Year of Publication
2017
Authors
Chester, A.
Ball, G. C.
Caballero-Folch, R.
Cross, D. S.
Cruz, S.
Domingo, T.
Drake, T. E.
Garnsworthy, A. B.
Hackman, G.
Hallam, S.
Henderson, J.
Henderson, R.
Korten, W.
Krucken, R.
Moukaddam, M.
Olaizola, B.
Ruotsalainen, P.
Smallcombe, J.
Starosta, K.
Svensson, C. E.
Williams, J.
Wimmer, K.
Name of Publication
Physical Review C
Volume
96
Pagination
6
Issue
1
Date Published
Jul
Short Title
Recoil distance method lifetime measurement of the 2(1)(+) state in Sr-94 and implications for the structure of neutron-rich Sr isotopes
Accession Number
WOS:000405203500001
ISBN Number
2469-9985
Keywords
Deformation, ions, nuclear-structure, Physics, tigress, tool, TRIUMF
Abstract

A high precision lifetime measurement of the 2(1)(+) state in 94Sr was performed at TRIUMF's ISAC- II facility by coupling the recoil distance method implemented via the TIGRESS integrated plunger with unsafe Coulomb excitation in inverse kinematics. Due to limited statistics imposed by the use of a radioactive 94Sr beam, a likelihood ratio chi(2) method was derived and used to compare experimental data to Geant4 simulations. The B(E2; 2(1)(+)-> 0(1)(+)) value extracted from the lifetime measurement of 7.80(- 0.40)(+0.50)(stat.)+/- 0.07(sys.) ps is approximately 25% larger than previously reported while the relative error has been reduced by a factor of approximately 8. A baseline deformation has been established for Sr isotopes with N <= 58 which is a necessary condition for the quantum phase transition interpretation of the onset of deformation in this region. A comparison to existing theoretical models is presented.