Speaker
Stefan Pavetich
(The Australian National University)
Description
Zirconium isotopes are predominantly produced by the slow neutron capture process. Maxwellian averaged cross sections (MACS) for neutron capture in the keV region are one of the key parameters to model this astrophysical process. They are particularly interesting in the mass region between 90-100 amu, as this is the matching area between the main and the weak component of the \text-process, taking part in two different stellar environments. However, significant uncertainties in the experimental data and deviations between theoretical predictions and experimental data for several neutron capture reactions in this mass region remain.
A combination of activation technique and accelerator mass spectrometry (AMS) was used to determine the MACS of the reaction 92Zr(n,gamma)93Zr. This method provides a different approach compared to previous time-of-flight (TOF) measurements and hence addresses different systematic uncertainties. Zirconium oxide pellets enriched in 92Zr were irradiated with a quasi-Maxwellian neutron spectrum of 30 keV at the Liquid Lithium Target beamline of the Soreq Applied Research Accelerator Facility. AMS measurements of the reaction product 93Zr were performed at the Heavy Ion Accelerator Facility (HIAF) of the Australian National University in Canberra. The main challenge in AMS of 93Zr is the interference from the stable isobar 93Nb. The high particle energies available at HIAF are ideal to tackle this challenge. Recently we have developed the technique to measure $^{93}$Zr with the required sensitivity and efficiency for such studies.
Here we will present preliminary AMS results for the 92Zr(n,gamma)93Zr capture cross section, which were found to be in fair agreement with the latest TOF measurement by Tagliente et al.
References
G. Tagliente et al. (The n-TOF collaboration), Phys. Rev. C {81}(2010)055801.
Primary author
Stefan Pavetich
(The Australian National University)
Co-authors
Alexander Carey
(The Australian National University)
Angelina Kinast
(Technische Universität München)
Prof.
Anton Wallner
(The Australian National University)
Asher Shor
(Soreq Nuclear Research Center)
Dominic Nelson
(The Australian National University)
Johannes Sterba
(Atominstitut, Technische Universität Wien)
Keith Fifield
(The Australian National University)
Leonid Weissman
(Soreq Nuclear Research Center)
Martin Martschini
(University of Vienna)
Michael Paul
(Racah Institute of Physics, Hebrew University)
Michaela Froehlich
(The Australian National University)
Mr
Moshe Tessler
(Hebrew University of Jerusalem)
Mr
Shlomi Halfon
(Hebrew University of Jerusalem and Soreq NRC)
Stephen Tims
(The Australian National University)
