1. Present and future of Geo-neutrinos Bill McDonough Geology, U Maryland

2. Plate Tectonics, Convection,Geodynamo Does heat from radioactive decay drive the Earth’s engine?

3. the future is… Geoneutrino studies Nature & amount of Earth’s thermal power radiogenic heating vs secular cooling estimates of BSE from 9TW to 36TW constrains chondritic Earth models estimates of mantle 1.3TW to 28TW layers, LLSVP, superplume piles -abundance of heat producing elements (K, Th, U) in the Earth -clues to planet formation processes -amount of radiogenic power to drive mantle convection & plate tectonics -is the mantle compositionally layered? or has large structures?

4. Summary of geoneutrino results SILICATE EARTH MODELS Cosmochemical: uses meteorites – 10 TW Geochemical: uses terrestrial rocks –20 TW Geodynamical: parameterized convection – 30 TW TW scales relative to U 10, 20, 30 TW ≈ 10, 20, 30 ppb

5. Constructing a 3-D reference model Earth assigning chemical and physical states to Earth voxels 1 o x 1 o x “z” tile mapping of elements Huang et al (2013) G-cubed arXiv:1301.0365 arXiv:1301.0365

6. Uranium Abundance in Middle Continental Crust layer Average middle Cont. Crust U abundance is  g/g Rudnick and Gao (2003) 1.3  g/g U MCC (  g/g)

7. Predicted Global geoneutrino flux based on our new Reference Model Huang et al (2013) G-cubed arXiv:1301.0365arXiv:1301.0365 10.1002/ggge.2012910.1002/ggge.20129 Geoneutrino detection rate --TNU: Terrestrial Neutrino Unit -- 1 TNU = one geoneutrino event per 10 32 free protons per year

8. Near Field: six closest 2° × 2° crustal voxels Far Field = bulk crust – near field crust

9. What’s hidden in the mantle? Seismically slow “red” regions in the deep mantle Can we image it with geonus? Ritsema et al (Science, 1999)

10. Testing Earth Models Mantle geoneutrino flux ( 238 U & 232 Th) Šrámek et al (2013) EPSL 10.1016/j.epsl.2012.11.001; arXiv:1207.085310.1016/j.epsl.2012.11.001arXiv:1207.0853

11. Slope = 1.0 The Mantle beneath the global array of detectors sees a uniform mantle flux (~10% variation) Intercept = ~8 TNU present uncertainty is large (±6 TNU), comparable to other recent reports

12. Predicted geoneutrino flux Mantle flux at the Earth’s surface Šrámek et al (2013) EPSL 10.1016/j.epsl.2012.11.001; arXiv:1207.085310.1016/j.epsl.2012.11.001arXiv:1207.0853 Yu Huang et al (2013) G-cubed arXiv:1301.0365 arXiv:1301.0365 10.1002/ggge.20129 Total flux at surface dominated by Continental crust dominated by deep mantle structures

13. Hanohano A Deep Ocean e Electron Anti-Neutrino Observatory Deployment Sketch Descent/ascent 39 min - multiple deployments - deep water cosmic shield - control-able L/E detection An experiment with joint interests in Physics, Geology, and Security Size: scalable from 1 to 50 kT 10-yr cost est: $250M @ 10 kT

14. 16 June 2008John Learned at LBL14 2 Candidate Off-shore Sites for Physics San Onofre, California- ~6 GW th Maanshan, Taiwan- ~5 GW th Need study of backgrounds versus depth

15. 16 June 2008John Learned at LBL15 Addressing Technology Issues Scintillating oil studies in lab –P = 450 atm, T = 0°C –Testing PC, PXE, LAB and dodecane –No problems so far, LAB favorite… optimization needed Implosion studies –Design with energy absorption –Computer modeling & at sea –No stoppers Power and comm, no problems Optical detector, prototypes OK Need second round design 20m x 35m fiducial vol. 1 m oil 2m pure water

16. Ocean Deployments Kilo Moana: U Hawaii operated UNOLS vessel, based at HNL UNOLS: University-National Oceanographic Laboratory System Sketch of prototype detector ~ 1m for deployment off Honolulu by Kilo Moana