"Isomer spectroscopy of very neutron-deficient 94Pd"
Timothy Brock, University of York
(id #53)
Seminar: YesPoster: No
Invited talk: No
The region of neutron-deficient nuclei close to 100Sn is remarkable for an abundance of isomeric states. Recent discoveries in this respect include high-spin states in 98Cd [1], 95Ag [2] and 94Ag [3]. Much discussion has focused on the decay modes of the latter, a (21+) state at an excitation energy of around 7 MeV with a half-life of 0.47 ± 0.08 s [4]. The apparent observation of a two-proton decay channel [5] for the state is especially interesting, but has been the subject of some debate [6]. Much of our understanding of this “unique” isomer comes from studies of its β-decay to 94Pd [3,4]. However, the ordering of states above 5 MeV that are fed by the β-decay of the 0.47 s isomer, together with their spins and parities, remains tentative.
In a recent RISING experiment at GSI, fragmentation of an 850 MeV/u 124Xe beam on a 9Be target was used to produce neutron-deficient nuclei near 100Sn. After separation and identification via the FRS and detectors at its central and final foci, nuclides of interest were implanted in a nine-DSSSD active stopper at the centre of the RISING array of germanium detectors in its stopped beam configuration [7]. The set-up allowed for both sub-millisecond-isomer and beta-delayed gamma-ray spectroscopy of the implants. New results from this data, focusing on isomeric decays in implanted 94Pd ions, will be presented showing a new isomeric state and shedding further light on the high spin states populated in the β-decay of the (21+) isomer in 94Ag.
References
[1]Blazhev A et al., Phys. Rev. C 69, 064304 (2004)
[2]Döring J et al., Phys. Rev. C 68, 034306 (2003)
[3]La Commara M et al., Nucl. Phys. A 708, 167-180 (2002)
[4]Plettner C et al., Nucl. Phys. A 733, 20-36 (2002)
[5]Mukha I et al., Nature(London) 439, 298-302 (2006)
[6]Pechenaya O L et al., Phys. Rev. C 76, 011304R (2007); Kankainen A et al., Phys. Rev. Lett. 101, 142503 (2008); Cerny J et al., Phys. Rev. Lett. 103, 152502 (2009); Jenkins D G, Phys. Rev C 80, 054303 (2009)
[7]Pietri S et al., Nucl. Inst. Meth. Phys. Res. B 261, 1079-1083 (2007)
In a recent RISING experiment at GSI, fragmentation of an 850 MeV/u 124Xe beam on a 9Be target was used to produce neutron-deficient nuclei near 100Sn. After separation and identification via the FRS and detectors at its central and final foci, nuclides of interest were implanted in a nine-DSSSD active stopper at the centre of the RISING array of germanium detectors in its stopped beam configuration [7]. The set-up allowed for both sub-millisecond-isomer and beta-delayed gamma-ray spectroscopy of the implants. New results from this data, focusing on isomeric decays in implanted 94Pd ions, will be presented showing a new isomeric state and shedding further light on the high spin states populated in the β-decay of the (21+) isomer in 94Ag.
References
[1]Blazhev A et al., Phys. Rev. C 69, 064304 (2004)
[2]Döring J et al., Phys. Rev. C 68, 034306 (2003)
[3]La Commara M et al., Nucl. Phys. A 708, 167-180 (2002)
[4]Plettner C et al., Nucl. Phys. A 733, 20-36 (2002)
[5]Mukha I et al., Nature(London) 439, 298-302 (2006)
[6]Pechenaya O L et al., Phys. Rev. C 76, 011304R (2007); Kankainen A et al., Phys. Rev. Lett. 101, 142503 (2008); Cerny J et al., Phys. Rev. Lett. 103, 152502 (2009); Jenkins D G, Phys. Rev C 80, 054303 (2009)
[7]Pietri S et al., Nucl. Inst. Meth. Phys. Res. B 261, 1079-1083 (2007)
