1. Liam Kieser, Ian Clark, Jack Cornett and Xiaolei Zhao, University of Ottawa Ted Litherland, University of Toronto Instrumentation Session, CAP 2014 Congress, Laurentian University, June 17 The André E. Lalonde Accelerator Mass Spectrometry Lab at the University of Ottawa

2. 1. Introduction – What is AMS? b) Ion-Gas Reactions and Isobar Separation 3.Advances in AMS Technology Overview 4.The New Facility at uOttawa - Summary a) Negative Ion Chemistry in the Ion Source a) Basic Description – Advantages, Applications, Challenges b) Lab Photo Tour – Principal Components c) Critical Component – the ion source a) Earth and Planetary Sciences 2.Design Goals for the Lalonde Lab b) Bio-medical and Pharmaceutical Sciences A. E. Lalonde AMS Lab c) Anthropological and Cultural Sciences d) AMS Research and Innovation

3. Accelerator Mass Spectrometry (AMS) A synthesis of: Conventional mass spectrometry, Particle accelerator technology -- usually a tandem electrostatic accelerator and Advantages: ■Molecular interference free measurements (Molecules destroyed in the charge changing process) ■Measurements with extremely low dark current (High energy -- 100s of keV to 10s of MeV provide single atom counting capability and some degree of atom identification) ■Atomic isobar elimination is special cases 14 C ( 14 N), 26 Al ( 26 Mg), 129 I ( 129 Xe), 202 Pb ( 202 Hg) Ion Source Filter or Analyzer Sample Detector Ions Heavier Ions Lighter Ions

4. Applications: Challenges: Need to make negative ions of the analyte (Tandem accelerator operation) Atomic isobars can be difficult to eliminate (except in the special cases) Concentration or isotope ratio measurements for long-lived radio-isotopes or rare atoms for dating or tracing e.g. 3 H, 10 Be, 14 C, 26 Al, 36 Cl, 41 Ca, Ag, 129 I, Pt group, actinides Used in Archaeometry, Astrophysics, Biology, Bio-medical research and clinical practice, Earth, Environmental and Planetary science, Materials research, Pharmacology Some sample materials require extensive, labour-intensive preparation e.g. 10 Be, 14 C Levels ranging from 1 part in 10 10 to 1 part in 10 16 Accelerator Mass Spectrometry (ctd)

5. AMS System Schematic: Tandem Accelerator Low Energy Mass Spectrometry Negative Ion Source High Energy Mass Spectrometry Gas Ionization Detector for rare species Faraday Cups for abundant species Sample Gas-Filled Electron Stripper Canal 3 MV Power Supply Electric Analyzer Magnetic Analyzer Electric Analyzer Accelerator Mass Spectrometry (ctd)

6. AMS System: View from Low Energy End Accelerator Mass Spectrometry (ctd)

7. AMS System: View from above the High Energy End Accelerator Mass Spectrometry (ctd)

8. The Ion Source → Development of the negative ion caesium sputter source in the 1970s made AMS possible Requirements: ►Large ion current (at least 10s of μA, 100s good if possible) to obtain sufficient counting statistics for low concentration of rare species with a large ratio to abundant species ►Stable operation for a variety of sample matrices ►Relatively low memory of previously analysed samples ►Produce negative ions from a wide range of elements Extraction Cone (ground potential) Sample (Target) -35 kV Caesium Ionizer Source Head Base -28kV Caesium Vapour feed

9. Ion Source HVE SO-110 200 sample, solid/gas ion source Sample Carousel Source Head Electric Analyser

10. Ion Source: Source Head Flange Target Cooling Lines Caesium Ionizer Target holder Caesium Vapour Feed On Maintenance Stand In Place Source head base / support -28 kV Target holder -35 kV

11. Target Wheel – capacity: 200 targets in 4 circles of 50 – access time to neighbour- ing target: ~2 seconds Ion Source:

12. Target Assembly – provides the micro- environment for the conversion of CO 2 into negative carbon ions – one assembly must be prepared for each 14 C measurement For solid materials – compress into a 1.3 mm Φ pellet in a replaceable Al or SS cylinder For gases Ion Source:

13. A. E. Lalonde AMS Lab Design Goals For Earth and Planetary Sciences: For Bio-medical and Pharmaceutical Sciences: For Anthropological and Cultural Sciences: - as wide a range of elements and isotopes as possible – from 3 H to 244 Pu - a full complement of ancillary equipment and sample preparation techniques IRMS, ICP-MS, Noble gas MS, electron microprobe - separate ion source lines to accommodate higher levels of tracer isotopes - gas ion source capability for interface to other analytical instruments, e.g. - specific sample prep labs for Radiocarbon, Radiohalides, Exposure age dating, noble gases and stable isotopes elemental analyzer for rapid or survey 14 C work GC or HPLC for compound specific 14 C work - similar to earth & planetary science requirements

14. For AMS Research: - flexible accelerator and peripheral design - accessible control electronics and software - sufficient floor space for tests of new injection and detection systems - support for continuation of research and development projects inherited from IsoTrace and beyond: c) Reaction Cells and Isobar Separation b) Integrated 14 C Sample Preparation and Analysis a) Negative Ion Chemistry in the Ion Source d) Laser – ion interactions ? Design Goals

15. a) Enhanced Production of Negative Ions Many elements do not readily make negative atomic ions But molecular ions can be used to carry the analyte to the accelerator terminal Fluoride materials make very strongly bound negative molecular ions and tend to produce much higher currents than those from the pure metal or Chemistry in the Ion Source Zhao et al Nuclear Instruments & Methods B 268 (2010) 807–811 2. Advances in AMS Technology Examples in the following two papers: Adam Sookdeo, using PbF 2 to develop a technique for measuring 210 Pb Cole MacDonald, using CsF 2 to develop a technique for measuring 135 Cs and 137 Cs

16. System schematic High Voltage Deck b) Ion - gas reactions to reduce isobar interferences: New AMS Technology Early work done with negative ions in a simple gas volume (Ferguson et al, Chem. Phys. Lett. 15 (1972) 257–259.) showed a chemical dependency of the negative ion destruction cross section. Work by Doupé, Tomski and Javahery confirmed that S – in a beam of Cl – could be selectively destroyed in NO 2. Funding for a Proof-of-Principle instrument and a patent obtained and the “Isobar Separator for Anions (ISA)” was built successfully tested.

17. Version uses a single cell for both cooling and reactions Lab Ground Deceleration Lenses Deceleration Quads Cooling / Reaction Cell Acceleration Quad, Lenses Lab Ground To Accelerator New AMS Technology

18. System as built –configuration used at IsoTrace High Voltage Deck (behind lucite shield) Off-axis Faraday Cup Vacuum Box Ion Source New AMS Technology

19. Exit Einzel Lens Entrance Einzel Lens ElectronicCard Cage Vacuum Baffle High Voltage Deck Insulator Stable Beam Attenuator Box Dual Stage Turbo Pump Interchangeable ISA Column Isobarex and the Lalonde AMS Lab are collaborating on the installation of a pre- commercial, demonstration version of the ISA. New AMS Technology Isobarex Corp. formed to develop and market ISA technology

20. Lalonde Lab Overall System New AMS Technology SIMS-type Ion Source Innovation Injector Line (U of Toronto components, Isobarex ISA column) 3 MV Multi-Element AMS system, built by High Voltage Engineering BV Isobar Separator ρ = 1.52 m Inflection Magnet SO-110-200 Ion Source 120° Spectrometer Magnet to accept 339 AMU at full source energy Additional turbopump and differential section for terminal stripper 90°, 351 MeV-AMU Analyzing Magnet 65° Cylindrical Electric Analyzer 20° Second High Energy Magnet 2 anode Ionization Detector Faraday Cup Box 54° Rotatable Electric Analyzer

21. Investigators, Affiliations and Acknowledgements Ian D. Clark W. E. (Liam) Kieser R Jack Cornett Xiao-Lei Zhao Gilles St-Jean Chris Charles A. E. Lalonde AMS Laboratory, University of Ottawa Lisa Cousins Gholamreza Javahery Ilia Tomski Ionics Mass Spectrometry Group Funding from: NSERC MRS, I2I and Discovery Grants Canada Foundation for Innovation Ontario Research Fund uOttawa Advanced Research Complex André E. Lalonde AMS Laboratory Jean-François Alary Chris Charles Isobarex Corp A. E. LitherlandIsoTrace Laboratory, University of Toronto