Slide 1

23 March 2013JGL at Geonu 20131 John Learned Univ. of Hawaii Future Large Liquid Scintillator Experiments For Geonu Studies and Much More Presentation at Neutrino Geosciences, Takayama, 23 March 2013

Slide 2

13 April 2009John Learned at Cornell2 Where do Neutrinos come from? We can study most of these with a deep ocean instrument! AstrophysicalAccelerators Soon ? Soon ?AstrophysicalAccelerators Nuclear Reactors (power stations, ships) Nuclear Reactors (power stations, ships) Particle Accelerator Earths Atmosphere (Cosmic Rays) Earths Atmosphere (Cosmic Rays) SunSun Supernovae (star collapse) SN 1987A SN 1987ASupernovae (star collapse) SN 1987A SN 1987A Earths Composition (NaturalRadioactivity) (NaturalRadioactivity) Big Bang (here 330 /cm 3 ) Indirect Evidence Indirect Evidence Big Bang (here 330 /cm 3 ) Indirect Evidence Indirect Evidence

Slide 3

A large deep underwater detector can address almost all of these neutrino sources! Many of them simultaneously. Low and high energy searches do not interfere. Nor do searches for rare phenomena such as supernovae and proton decay. Such an instrument is not just one experiment yielding one number, but will supply a huge variety of results (and PhDs) and can engage a large scientific community. This is true in geology as well as particle physics and astrophysics 23 March 2013JGL at Geonu 20133

Slide 4

Geology Involvement Studies to decide on locations for detector: Ocean bottom cores, region studies Development of pile and other models Best possible regional calculations Studies on spectra expected: Close examination of U/Th decay chains and beta decays Pressure effects? Improvement of earth models: Tuning various models with working groups Crucial temperature and seismic studies in less know regions? Sharpening community focus on earth heat issues Engaging the whole Geo Community in a project touching many specialities Seeking lateral variation and possible explanations, hidden reservoirs We need a large multidisciplinary team to put this all together, not just physicists. 23 March 2013JGL at Geonu 20134

Slide 5

The Road to Geonu Science 23 March 2013JGL at Geonu 20135 Know we need great mass detectors > kiloton scale -> megaton scale Only (presently) viable technology is large tanks of liquid scintillator Difficult to resolve mantle from crust at continental locations Best to be far from nuclear reactors = mid-ocean Need to be deep to avoid background (>3km) Ocean offers potential for relocation to multiple sites We can start with what we have now, all technology exists Challenges to do even better and go further than just local geonu rate: Better scintillator (output, water based, attenuation length) New optical detectors, better coverage and time resolution Directionality? K40 nus from the earth?

Slide 6

Large Electron Anti-Neutrino Experiments* Continuing Experiments KamLAND 1 kTLS 2 kmwe 1 MeV Borexino 0.4 kTLS 3 kmwe 1 MeV Near Term SNO+ 1kT LS+ 4 kmwe 1 MeV SK (w/Gd?) 22kTH2O+Gd 2 kmwe 4 MeV Proposed HyperK 600kTH2O+? 1.5 kmwe(?) 6 MeV DayaBay2 20kTLS 1.5 kmwe 1 MeV RENO50 5kTLS ? kmwe 1 MeV LENA 50kTLS 3 kmwe 1 MeV LBNE Homestake 17kTLar 0 or 4 kmwe 100 MeV? Watchman 1kTH2O+Gd 0.3 kmwe 4 MeV Hanohano 10kTLS 2-5 kmwe 1 MeV 23 March 2013JGL at Geonu 20136 *Neglecting MINOS and NOVA, INO and MiniBOONE detectors, not relevant to this discussion on MeV electron anti-neutrinos. (And also to keep the list manageable herein.)

Slide 7

Rough Physics Domains of Large Nuebar Experiments PhysicsKLBXSNO+SK w/HKDB2RN50LENAHstk LAr* WatchHano Reactor Mon Reactor Hierarchy Geonu Det. Geonu Mantle CR nus Indirect DM SN nus Relic SN nus No Nu LBNE 13 ? ? LBNE CPV ? PDK 23 March 2013JGL at Geonu 20137 * Assuming 37 kT and deep

Slide 8

13 April 2009John Learned at Cornell8 Locations for Present & Possible Geonu Experiments Color indicates U/Th neutrino flux, mostly from crust Kamland SuperK HyperK Baksan Hanohano EARTH ? LENASNO+ Borexino LBNE LAr DayaBay2

Slide 9

13 April 2009John Learned at Cornell9 Simulated Geoneutrino Origination Points KamLAND 50% within 500km 25% from Mantle Assumeshomogeneous mantle & no core source In Mid-Ocean 70% Mantle 30% Other Sanshiro Enomoto

Slide 10

13 April 2009John Learned at Cornell10 Why we need Geonu measuements in the deep ocean to measure the Mantle Contribution Steve Dye mantle Mantle Models 16-18 typical 12-39 extreme Crust Only

Slide 11

13 April 2009John Learned at Cornell11 With a deep ocean detector we could resolve a Single Reactor Source at CMB resolution to few km10 sample simulated 1 yr runs 1 GW source observed by 100 kT detector can be cleaned up

Slide 12

13 April 2009John Learned at Cornell12 What Next for Geonus? Measure gross fluxes from crust and mantle Discover or set limits on georeactors. Better earth models Explore lateral homogeneity Use directionality for earth neutrino tomography Follow the science.

Slide 13

Applied Neutrinos! Program to Study Long Range Reactor Monitoring and Detection Working with colleagues at UH, NGA and IAI in US. Studies using all available neutrino tools: Hypothetical large detectors (100kT class) Assume availability of new photodetectors (LAPPDS of the like) Use oscillations fully in analysis Calculate full backgrounds including earth model and detector depth Use full Max Liklihood, with Bayesian statistics Test importance of directional detection (obvious answer: very big boost) Conclusions: Works better than we had guessed big paper in press in Physics Reports. Will show some pictures here. 23 March 2013JGL at Geonu 2013 13

Slide 14

23 March 2013JGL at Geonu 201314 mTC Idea Do imaging with (100 ps) fast timing, not optics (time reversal imaging). Small portable 2.2 liter scintillating cube, Boron doped plastic. 4 x 6 MCP (x64 pixels each) fast pixel detectors on surrounding faces Get neutrino directionality. Reject noise on the fly. ~10/day anti-neutrino interactions (inverse beta decay signature) from power reactor (San Onofre). 13 cm 2.2 liter First, testing out new technology for precise antineutrino detection at UH

Slide 15

23 March 2013JGL at Geonu 201315 mTC Virtues Small size avoids positron annihilation gammas which smear resolution (X o ~42 cm).... gammas mostly escape, permitting precise positron creation point location. Fast pixel timing (

13 April 2009John Learned at Cornell38 Summary of Expected Results Summary of Expected Results Hanohano- 10 kt-1 yr Exposure Neutrino Geophysics- near Hawaii Mantle flux U geoneutrinos to ~10% Heat flux ~15% Measure Th/U ratio to ~20% Rule out geo-reactor if P > 0.3 TW Neutrino Oscillation Physics- ~55 km from reactor Measure sin 2 ( 12 ) to few % w/ standard -cycle Measure sin 2 (2 13 ) down to ~ 0.05 w/ multi-cycle m 2 31 to less than 1% w/ multi-cycle Mass hierarchy w/multi-cycle & no near detector; insensitive to background, systematic errors; complementary to Minos, Nova Much other astrophysics and nucleon decay too.

Slide 39

13 April 2009John Learned at Cornell39 Additional Physics/Astrophysics Hanohano will be biggest low energy neutrino detector (except for maybe LENA) Supernova Detection: special e ability Relic SN Neutrinos GRBs and other rare impulsive sources Exotic objects (monopoles, quark nuggets, etc.) Long list of ancillary, non-interfering science, with strong discovery potential Broad gauge science and technology, a program not just a single experiment.

Slide 40

Other Applications for a large deep-water neutrino detector Long Baseline with accelerators ~ 1 GeV Hanohano with Tokai Beam (between Japan and Korea)? LENA with CERN beam?? New LBNE Experiment with Fermilab Beam?? Nucleon Decay (high free proton content) view details of decays such as Kaon modes Particle Astrophysics (low mass WIMPS,) + All the low energy physics (geonus, reactor studies, monitoring, solar neutrinos..) unimpeded! 23 March 2013JGL at Geonu 201340

Slide 41

What now? We are ready to plan for a large deep ocean neutrino detector To study geology And much else We need a large interdisciplinary and multinational team to pull this off Many areas of expertise needed Please consider how you can help 23 March 2013JGL at Geonu 2013 41