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

Determining the spectroscopic quadrupole moment (Q<sub>s</sub>) of the first 2<sup>+</sup> state in <sup>40</sup>Ar

1 Jul 2015, 16:10
1h 50m
Board: B.295
Poster Presentation Track B - Nuclear, Particle and Radiation Physics Poster2

Speaker

Mr Makabata Jeremia Mokgolobotho (University of the Western Cape)

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

No

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

MSc

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>

The present study aims at determining the spectroscopic quadrupole moment Qs, for the first 2+ excited state in 40Ar by carrying out the first order Coulomb-excitation reorientation-effect measurements of 40Ar beams at safe energies. Only one such measurement [1]was done in the 1970's with unsafe beam energies. We have used the 208Pb (40Ar, 40Ar)208Pb reaction at 143.2 MeV, for which the minimum distance of closest approach between the nuclear surfaces is ~ 6.6 fm. The first 2+ state at 1460 keV in 40Ar is populated via Coulomb-excitation and the de-excited γ-rays are detected using the AFFRODITE clover detector array[2] which comprises of 8 HPGe detectors (5 at 90° and 3 at 135°). The scattered particles are detected in coincidence with γ-rays using a double sided S3 silicon detector which consists of 24 rings (for angular distribution) on one side and 32 sectors (for Doppler correction) on the other. These measurements were done at low beam currents of ~0.5 nA and with the target (1mg.cm-2 208Pb) positioned at 10.05 mm from the S3 detector at backward angles to be sensitive to Qs. The integrated γ-ray yields per ring carry information about the Qs(2+) value and will be compared with the semi-classical coupled-channel Coulomb-excitation code GOSIA.

References :
1)R. H. Spear, Phys. Rep. 73, 369 (1981).
2) M. Lipoglavsek et al., Nucl. Instr. Meth. Phys. Res., A557, 523 (2006).

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

Yes

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

Nico Orce
njorce@uwc.ac.za
University of the Western Cape

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

Yes

Primary author

Mr Makabata Jeremia Mokgolobotho (University of the Western Cape)

Co-authors

Ms Bernadette Rebeiro (University of the Western Cape) Mr Bhivek Singh (University of the Western Cape) Mr Craig Mehl (University of the Western Cape) Dr M. Kumar Raju (University of the Western Cape) Dr Mathis Wiedeking (iThemba LABS) Mr Nicholas Erasmus (University of the Western Cape) Prof. Nico Orce (University of the Western Cape) Ms Ntombi kheswa (iThemba) Dr Pete Jones (iThemba LABS) Dr Phillip Adsley (iThemba LABS and Stellenbosch University) Dr Rainer thomae (iThemba) Dr Rob BARK (iThemba LABS) Prof. Smarajit Triambak (University of the Wester Cape) Dr Tshepo Dinoko (iThemba LABS) Prof. paul papka (Stellenbosch University)

Presentation Materials

There are no materials yet.