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VERA Seminar

Gemeinsames VERA-SMI Seminar
Stefan-Meyer-Institut für subatomare Physik, Seminarraum

Quasi-free neutron decay of the halo nucleus 11Be

Oliver Forstner, Faculty of Physics, University of Vienna and Stefan-Meyer-Institute of the Austrian Academy of Sciences

for the IS541 Collaboration @CERN

The Q-value of the beta-minus decay from 11Be to 11B is 11.509 MeV, which is above the binding energy of a proton in 11B. Therefore the one-neutron halo nucleus 11Be can emit a proton in the beta decay of the halo neutron. However, due to the Q-value of this decay channel (280.7±0.3 keV) the expected branching ratio will be very low – most estimates are a few times 10-8 – and the detection of the outgoing proton with a kinetic energy of a few hundred keV is challenging. Therefore a new approach was pursued detecting the remaining nucleus 10Be with the help of accelerator mass spectrometry (AMS). To study this rare decay a beam of 11Be ions was produced at the radioactive ion beam facility ISOLDE at CERN and implanted in a copper collection sample. The sample was transferred to the VERA AMS facility at the University of Vienna where the 10Be content was determined through a 10Be/9Be ratio measurement.
After an introduction into the physics of halo nuclei I will present experimental details of the collection at ISOLDE and the AMS measurement at VERA as well as results of the successful detection of this rare decay channel.

Donnerstag, 16.01.2014    16:30 Uhr
Stefan-Meyer-Institut für subatomare Physik, Seminarraum 2.08
Boltzmanngasse 3/ 2.Stock
1090 Wien

 Abstract

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