28 June 2015 to 3 July 2015
Africa/Johannesburg timezone
SAIP2015 Proceeding published on 17 July 2016

Extraction of statistical properties in 181Ta to investigate nucleo-synthesis of 180Ta

3 Jul 2015, 12:10
20m
Oral Presentation Track B - Nuclear, Particle and Radiation Physics NPRP

Speaker

Mr Kgashane Malatji (UWC)

Main supervisor (name and email)<br>and his / her institution

Mathis Wiedeking ( wiedeking@tlabs.ac.za), iThemba LABS

Please indicate whether<br>this abstract may be<br>published online<br>(Yes / No)

Yes

Apply to be<br> considered for a student <br> &nbsp; award (Yes / No)?

Yes

Would you like to <br> submit a short paper <br> for the Conference <br> Proceedings (Yes / No)?

No

Abstract content <br> &nbsp; (Max 300 words)<br><a href="http://events.saip.org.za/getFile.py/access?resId=0&materialId=0&confId=34" target="_blank">Formatting &<br>Special chars</a>

Most stable and extremely low abundance proton-rich nuclei with A>110 are thought to be produced by the photodisintegration of s- and r- process produced nuclei. However, this p-process is insufficient to explain the observed low abundance (0.012%) of the180Ta isotope. Hence combinations of several processes are considered to reproduce 180Ta in the cosmos, provoking debates and making it a unique case study. Significant errors in the predicted reaction rates in some of the p-nuclei can arise due to large uncertainties in nuclear properties such as the nuclear level densities (NLD) and gamma-ray strength functions (γSF) [1]. An experiment was performed in October 2014 to extract the γSF and NLD below the neutron threshold in 180,181,182Ta which provide important input parameters for nuclear reaction models. In the present case study, these parameters were measured using the 181Ta(3He, 3Heγ)181Ta inelastic scattering reaction with 34MeV beam energy at the Oslo Cyclotron Laboratory. Using the SiRi array at backward angles (64 silicon particle telescopes) and the CACTUS array (26 NaI(Tl) detectors), the NLD and γSF were simultaneously extracted from particle-γ coincidence matrices through iterative procedures using the Oslo method [2]. These results will be used to determine the corresponding neutron capture cross sections which in turn will be utilized in astrophysical network calculations to investigate the galactic production mechanism of 180Ta. I will present preliminary results of this investigation of statistical properties for 181Ta.

Level for award<br>&nbsp;(Hons, MSc, <br> &nbsp; PhD, N/A)?

MSc

Primary author

Co-authors

Prof. Andreas Görgen (University of Oslo) Dr Ann-Cecilie Larsen (University of Oslo) Dr Bonginkosi Kheswa (IThemba LABS) Dr Darren Bleuel (Lawrence Livermore National Laboratory) Dr Eda Sahin (University of Oslo) Mr Fabio Zeiser (University of Oslo) Dr Francesca Giacoppo (University of Oslo) Mr Frank Bello Garrote (University of Oslo) Dr Gry Tveten (University of Oslo) Dr Hilde Nyhus (University of Oslo) Dr Kasia Hadynska-Klek (University of Oslo) Prof. Magne Guttormsen (University of Oslo) Ms Malin Klintefjord (University of Oslo) Dr Mathis Wiedeking (iThemba LABS) Prof. Smarajit Triambak (UWC) Ms Sunniva Rose (University of Oslo) Prof. Sunniva Siem (University of Oslo) Ms Therese Renstrøm (University of Oslo) Ms Trine Hagen (University of Oslo) Mr Vetle Ingeberg (University of Oslo)

Presentation Materials