Current Status of the Canadian Penning Trap Mass Spectrometer at CARIBU

1. Current Status of the Canadian Penning Trap Mass Spectrometer at CARIBU Graeme Morgan 2014 Cap Congress

2. How are heavy elements formed? r-process thought to produce almost half of the elements heavier than Iron.

3. r-process High neutron density and temperature required. Neutron capture and photodissociationreactions compete with each other. -decay brings the nuclei to a higher Z. Reaction ends when density and temperature drop and the nuclei decay to stability. J. Van Schelt – PhD Thesis 2012

4. Where do we come in? r-process reaction rates and path location are dependent on neutron separation energies . We can measure those masses!

5. Californium Rare Isotope Breeder Upgrade - CARIBU • source inside Gas Catcher • Isobar Separator • Resolution of approximately 1/14000 • Low energy beamline with RFQ Buncher • Beams can be sent to ATLAS to be re-accelerated for other experiments J. Van Schelt – PhD Thesis 2012 J. Clark and G. Savard/Int. Journal of Mass Spectrometry 349-350 (2013) 81

6. Changes to CARIBU New source! • 1.7Ci source recently installed Multi-reflection time-of-flight (MR-ToF) mass separator to be constructed and installed by the end of 2014. R. N. Wolf et. al./Nucl. Instr. and Methods in Physics Research A 686 (2012) 82

7. We hope to obtain clean beam production of species with fission branches on the order of - Proposed measurements

8. How to Measure Masses Frequencies can be measured with high precision. A charged particle in a B-field moves in a circular orbit at it’s cyclotron frequency .

9. The Canadian Penning Trap Particles held by a quadrupole trapping potential along the B-field axis. Potential created by shaping the trap electrodes as two hyperboloids of revolution. J. Clark – PhD Thesis 2005

10. Ion Motion in Trap Quadrupole potential provides an axial oscillation independent of B. is split into 2 eigenfrequenciesdue to the radial repulsion. • can be applied as a dipole excitation if the ring electrode is cut in half. • Increases ion orbit radius. L. Brown and G. Gabrielse/Rev. Mod. Phys. 58 (1986) 233 =

11. Application of the sum of the two frequencies as a quadrupole is possible with the ring electrode cut into quarters. orbit is converted to a orbit of the same radius, giving a increase in frequency and a increase in orbital energy. J. Van Schelt – PhD Thesis 2012

12. TOF Detection Linear Energy Time of Flight Method Channeltron Isotopes examined during Summer 2013 93Sr, 95Sr, 93Rb, 106Mo, 106Tc, 134I-m, 134I-g, 142I, 147Cs, 148Cs, 146La-m, 146La-g, 148Ba, 149Ba, 150Ba, 162Sa, 162Eu, 164Eu, 165Gd Magnetic field lines outside the Penning trap Orbital Energy Figure by D. Lascar Ions ejected from the Penning trap

13. CPT Detector Upgrade Replacing current Channeltron detector with a position sensitive MCP Enables phase-imaging ion-cyclotron resonance (PI-ICR) measurements

14. PI-ICR Measurements The orbital frequency of the ion’s motion is calculated from the phase change over time. The position of the ion in the trap is projected onto the MCP when ejected. is determined through a ToF measurement of frequency. S. Eliseev et. al./Phys. Rev. Lett. 110 (2013) 082501 Ions from the Penning trap

15. What do we gain? • Contaminants become less of an issue. • No cleaning before an excitation means less time spent in the trap quicker measurements shorter half lives. • Less statistics required. • Each ion can be identified compared with ToFmeasurements. Easier to reach isotopes with lower yields. • Resolution is not only given by time spent in the trap; it can also be improved by increasing the orbit radius or reducing the radial spread.

16. CPT Collaboration P. Bertone, J.A. Clark, A. Perez Galvan, A.F. Levand, G. Savard A. Chaudhuri,G. Morgan, K.S. Sharma S. Caldwell, J. Van Schelt, M. Sternberg F. Buchinger, J.E. Crawford, G. Li, R. Orford D. Lascar, R. Segel A. Aprahamian, S. Marley, M. Mumpower, A. Nystrom, N. Paul, K. Siegl, S. Y. Strauss, R. Surman

17. S. Eliseev et. al./ Appl. Phys. B 114 (2014) 107