Download - 20 January 2005Steve Dye, HPU1 Neutrino Geophysics in Hawaii Presentation by Steve Dye Associate Professor of Physics Hawaii Pacific University January

20 January 2005 Steve Dye, HPU 1

Neutrino Geophysics in Hawaii

Presentation by Steve DyeAssociate Professor of Physics

Hawaii Pacific University

January 20, 2005


Outline of Presentation

Neutrinos Geophysics Neutrino Geophysics HANOHANO


Neutrinos

Discovery Place in nature Properties Detection

– Astrophysics– Nuclear reactors

http://www.flyingneutrinos.com


Discovery of Neutrino W. Pauli proposes

undetected particle in β-decay (1931)

E. Fermi develops theory of β-decay with “little neutral one” (1934)

C. Cowan and F. Reines detect neutrinos at nuclear reactors (1950's) http://www.ps.uci.edu/physics/reinesphotos.html


Neutrino’s Place in Nature

http://www.particleadventure.org/particleadventure/frameless/chart.html


Neutrino Properties

Come in three flavours– e, μ, τ

No electric charge Stable Weak interactions Massive (slightly) Flavour oscillations


Neutrino Detection

http://www.ps.uci.edu/physics/reinesphotos.html

http://www-sk.icrr.u-tokyo.ac.jp/doc/sk/photo/normal.html

http://www-personal.umich.edu/~jcv/IMBdiverbig.jpg


Neutrino Astrophysics

Neutrinos are excellent astrophysical probes– Stable, uncharged, weakly-interacting

Low energy (eV scale)– Detection of “Big Bang” neutrinos difficult

Medium energy (MeV scale)– Detection of stellar neutrinos established

High energy (TeV to EeV scale)– Detection of extragalactic neutrinos

progressing


Neutrino Astrophysics- SN1987a

http://www-personal.umich.edu/~jcv/imb/imbp5.html


http://elvis.phys.lsu.edu/svoboda/superk/cossun.pdf http://elvis.phys.lsu.edu/svoboda/superk/sun.gif


Neutrinos from Nuclear Reactors

http://www.insc.anl.gov/pwrmaps/map/world_map.php


Underground Neutrino Detector

KamLAND in Japan– 1000 tonnes of

liquid scintillator– ~2000 PMTs– Rate in 400 tonnes

~1/(2 days) from reactors at 180 km


Anti-Neutrino Detection

from John G. Learned “Monitoring All Earth Reactors”


Neutrinos in Japan KamLand signal

primarily neutrinos from nuclear reactors

Neutrinos from Earth detected!

Raghavan hep-ex/0208038


Summary Point #1

Neutrinos exist with measured properties

Neutrinos carry information from deep inside stars, galaxies, and Earth

Neutrinos of energy ~1 MeV can be detected using proven techniques


Geophysics

http://www.solarviews.com/cap/earth/earthfg2.htm


Seismology Earthquake waves

– Pressure waves• P (primary) waves

– Shear waves• S (secondary) waves

Solids– Transmit P and S

waves Fluids

– Transmit only P waves

http://www.mantleplumes.org/Energetics.html


Earth’s Interior

http://mantleplumes.org/Energetics.html


Geodynamo

Magnetic field– Dipole– Convection in outer

core– Rotation of Earth

Magnetic field required for life to exist– Deflects radiation– Helps retain

atmospherehttp://www.es.ucsc.edu/~glatz/geodynamo/html


Global Heat Flow

http://www.geo.lsa.umich.edu/IHFC/heatflow.html

http://www.geo.lsa.umich.edu/IHFC/heatflow.html

>24,000 field measurements


Earth Radioactivity Long-lived radioactive isotopes Decay of heavy elements heats the Earth How much heat and from where are the main

questions U/Th/K distribution in the core, mantle, crust

http://neutrino2004.in2p3.fr/slides/monday/fiorentini.pdf


Summary Point #2

Much to be learned in geophysics– Composition of mantle and core– Origin of Earth– Source of heat flow– Mechanism of geodynamo


Geo-neutrinos

Anti-neutrinos from the Earth

Arise from decay of radioactive elements (U+Th+K) in crust, mantle, and maybe core

Detection above 1.8 MeV proven (U+Th)

Domogatsky et al., hep-ph/0409069

Rothschild, Chen and Calaprice: nucl-ex/9710001


Geo-neutrinos

Contributions from continental crust, oceanic crust, and mantle

Possible observational sites– Japan– Italy– Canada– Russia– Curacao– Hawaii


Geo-neutrinos at Curacao

Dutch project– Long, narrow

underground shafts– Instrumented with

nuclear detectors– Strives to measure

neutrino direction Goal: Neutrino

tomography of Earth

R.J. de Meijer EARTH Info-001


Anti-Neutrinos from the Core

J. Marvin Herndon Breeder (fission)

reactor deep within inner core

Explains heat flow, geomagnetic field variability, He3/He4

Power output 3-10 TW Observable through

neutrino emission


Geo-reactor neutrinos

Test of geo-reactor hypothesis requires special location for clear signal– Far from man-made

reactors– Far from continental

crust Hawaii is excellent

siteRaghavan hep-ex/0208038


HANOHANO(Hawaiian for magnificent)

Hawaii Anti-Neutrino Observatory New initiative in Hawaii for neutrino geophysics

project Objectives are:

– Measure geo-neutrinos from mantle and U/Th– Test geo-reactor hypothesis

Method:– Deploy KamLAND-like detector in the deep (4-5 km) ocean

near Hawaii and operate for about 1 year Funding:

– Submitting proposal to CEROS next week for design study– If successful, propose CEROS follow-on for prototype testing– Next go for order of $100M from NSF for full detector


Deep Ocean Technology

Hawaii-2 Observatory– Deployed in 1998– Another off Japan ’93

Neutrino detector possible in 3-5 years

http://oceanusmag.whoi.edu/images/v42n2-chave1en.jpg


Summary and Conclusion

Neutrino detection is a viable (only?) method for learning what is inside Earth

Various neutrino geophysics projects being considered around the globe

Hawaii is an excellent site for a project Deep ocean technology sufficiently

advanced HANOHANO

Download - 20 January 2005Steve Dye, HPU1 Neutrino Geophysics in Hawaii Presentation by Steve Dye Associate Professor of Physics Hawaii Pacific University January

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