EPJ Web of Conferences (Dec 2012)

Level lifetimes and quadrupole moments from Coulomb excitation in the Ba chain and the N = 80 isotones

  • Seweryniak D.,
  • Rapisarda E.,
  • Rainovski G.,
  • Pakarinen J.,
  • Pietralla N.,
  • Möller T.,
  • Möller O.,
  • Leske J.,
  • Guastalla G.,
  • Bauer C.,
  • Stahl C.,
  • Stegmann R.,
  • Wiederhold J.,
  • Zhu S.

DOI
https://doi.org/10.1051/epjconf/20123810003
Journal volume & issue
Vol. 38
p. 10003

Abstract

Read online

The chain of Barium isotopes enables us to study experimentally the evolution of nuclear quadrupole collectivity from the shell closure at N = 82 towards neutron-deficient or neutron-rich deformed nuclei. The TU Darmstadt group has investigated several nuclei from stable 130,132Ba up to radioactive 140,142Ba with the projectile-Coulomb excitation technique including the use of the Doppler-shift attenuation method (DSAM). Lifetimes of quadrupole-collective states of 132Ba and 140Ba were obtained for the first time as well as the static electric quadrupole moments Q(21+) for 130,132Ba and 140,142Ba. The results are compared to Monte Carlo shell model and Beyond-Mean-Field calculations. The phenomenon of shell stabilization in the N = 80 isotones is further investigated by measurements of the B(E2;21+ → 01+) values of 140Nd and 142Sm and comparison to the quasi-particle phonon model and shell-model calculations.