1. Search for Neutrinoless double beta-decays with the Enriched Xenon Observatory Derek Mackay and Nicole Ackerman

2. What are we doing here?

4. Moving the Clean Rooms (x 6)!

5. The Xe vessel HFE (Heat transfer fluid) Vacuum insulation 25cm enclosure of low activity lead

6. EXO TPC Detector Inside Xenon Vessel

7. EXO’s Crown Jewels Largest enriched isotope stockpile in the world unrelated to the Nuclear Weapon/Energy Industry

8. Russian Enrichment Facility Part of EXO Funding rationalization was to keep enrichment Facilities Occupied with non-Nuclear Weapon Activities

9. LHe cryostat SXe-coated tip LXe cell Actuator Next Generation EXO- Barium Tagging Can potentially completely eliminate background events

10. Vcos(Ωt) + U U DC potential [V] 0 Volts -5 Volts CCD Scope Spectroscopy lasers Quadrupole Trap for Ba Ions

11. 2 P 1/2 4 D 3/2 2 S 1/2 493nm 650nm metastable 47s Identifying the Barium

12. EXO-200 Case 186133 Majorana mass (meV) QRPA 1 NSM 2 40 Radioactive Background (events) 6.4*10 25 1.6 * 2700.2 T 1/2 0ν (yr, 90%CL) σ E /E @ 2.5MeV (%) Run Time (yr) Eff. (%) Mass (ton) EXO-200 Sensitivity (Current Experiment) Next Generation EXO Sensitivity Aggressi ve Conserva tive Case 7.3 33 5.3 24 Majorana mass (meV) QRPA 1 NSM 2 1 1 2νββ Background (events) 4.1*10 28 1†1† 107010 2*10 27 1.6 * 5701 T 1/2 0ν (yr, 90%CL) σ E /E @ 2.5MeV (%) Run Time (yr) Eff. (%) Mass (ton)

13. EXO Schedule Current Status: All Clean Rooms are underground and are in the process of being reassembled. March 2008: Complete a full cool down test of the system (full test except for the actual detector – a test chamber will be used instead) August 2008: Complete cool down test with actual detector with natural “cheap” Xenon. Fall 2008: Start Data run with enriched Xenon