νννThe Importance of Neutrinos
andSome New Experiments to Measure ThemJohn G. Learned
University of Hawaii, Manoa

John Learned at Tohoku Forum for Creativity

27 October 2016

27 October 2016

νInternational Workshop：Neutrino Research and Thermal Evolution of the Earth

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With Many thanks to UH Neutrino Group , KamLAND, mTC, and NuLat Collaboration Colleagues

So, what IS a Neutrino?
This was a Neutrino

2

Stable Elementary Particle – 3 of 6 constituents of matterNo electric charge – cannot see it
Very little interaction with matter – goes through the earth unscathedHas very little mass – less than 1 millionth of electron
Lots of them though – 100 million in your body any time!

John Learned at Tohoku Forum for Creativity

27 October 2016

This is a NeutrinoElectrons
Nucleus
Neutron27 October 2016

ProtonQuarksJohn Learned at Tohoku Forum for Creativity

Atom

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Subatomic Structure

t

up

charm

topdsbdown

strangebottomeμτelectron

muon

tauon

νeνμντ

electronneutrino

muon
neutrino

27 October 2016

cJohn Learned at Tohoku Forum for Creativityutau
neutrino
4

Leptons

QuarksunstableWhere do Neutrinos come from?

 Particle Accelerator

Supernovae(star collapse)
SN 1987A  Earth’s Atmosphere

AstrophysicalAccelerators
IceCube(Cosmic Rays)

Earth’s Crust(NaturalRadioactivity)



Big Bang(here 330 ν/cm3)
Indirect Evidence

27 October 2016

Sun

John Learned at Tohoku Forum for Creativity

Nuclear Reactors(power stations, ships)

5So why are neutrinos important?
Anthropic view: Keep physicists busy figuring out why and how….

Daily use? None! (Yet, but history of electron and many others)

27 October 2016

Very unusual properties… shape shifters, totally unpredicted

Learning about the interior of sun and earth.
Monitoring nuclear reactors unintrusively and remotely
Communication? Expensive on earth (but crazy fast traders…)
Maybe ultimately with ET?
Neutrinos are Fundamental to our existence… and useful too.

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Supernovae explosions produce nu’s in horrendous numbers,
and are associated with the production of elements heavier than ironJohn Learned at Tohoku Forum for Creativity

Produced in abundance in Big Bang (associated with excess of matter?)Radioactive Beta Decay

Proton“Neutrino”(E.Fermi)

Niels Bohr:
Energy not strictly“Neutron”
Wolfgang Pauli
Conserved in the(1900-1958)(1930)
microscopic domain?
Nobel Prize 1945

John Learned at Tohoku Forum for Creativity

Beta (Electron) Energy

7Neutron

27 October 2016

Spectrum

How were Neutrinos discovered?

Anti-Electron
Neutrinos
νefrom
Hanford
Nuclear
ReactorFred Reines(1918 – 1998)
Nobel Prize 1995

nDetector Prototype

Cdγ
γ

pe+e-γ

3 gammaquanta incoincidence

8

Clyde Cowan(1919 – 1974)

John Learned at Tohoku Forum for Creativity

27 October 2016

First Detection ! (1954 - 1956)

First Observation of Solar Neutrinos

Homestake Solar-Neutrino
Observatory (since ca.1967)

9600 Tons
Cleaning Fluid

John Learned at Tohoku Forum for Creativity

27 October 2016

Inverse Beta-Decay(“Neutrino Capture”)

The Original Solar Neutrino Deficit
Homestake

88B
B

Calculation the
expected fractionof solar neutrinos
from various
reactionsJohn Bahcall

CNO
CNO
77Be

Be

Measured (1967 –1995)
Raymond Davis Jr. Nobel ‘02

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Uncertainty

John Learned at Tohoku Forum for Creativity

27 October 2016

ChlorineJohn Learned at Tohoku Forum for Creativity
11They change from one type (e, mu, tau)
to another (and back again)as they fly along.

27 October 2016

Neutrinos are Shape Shifters!

Mixture of Neutrinos of Various Masses

Mass m1

Mass m2 >= m1

Neutrino oscillation is a wave phenomenon(Wave-Particle Duality)

27 October 2016
John Learned at Tohoku Forum for Creativity

Neutrino
Mass m2) 12

ElectronNeutrino

Neutrino
Mass m1

Mass m1

Oscillation Length
4 πE
m22 − m1213

Mass m2 > m1

John Learned at Tohoku Forum for Creativity

27 October 2016

Neutrino Oscillations

John Learned at Tohoku Forum for Creativity

Oscillation Length
4 πE1427 October 2016

Neutrino Oscillations

m22 − m12

SuperKamiokande

SNO (Deuterium)

Chlorine

GalliumWaterνe+d→p+p+e− ν + d → p + n + ν

8B

CNO
8B

CNO
7Be

7Be
8B

8B

8B

pp

Electron-Neutrinos

All Neutrino
Types

John Learned at Tohoku Forum for Creativity

Gallex/GNOSAGE

15Homestake

27 October 2016

The Solar Neutrino Deficit Resolved

John Learned at Tohoku Forum for Creativity

detect νefrom >100kmand observe
deficit due tooscillations• ~1 neutrino
capture perday• Taking data
since Jan. ‘02• ConclusiveResults
Fall ’02.

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Japanese
nuclearreactors
60 GW(20%worldtotal)

27 October 2016

KamLAND Reactor Neutrino Experiment (Japan)

17John Learned at Tohoku Forum for Creativity

27 October 2016

KamLAND Settles the Solar Problem

Atmospheric Neutrino Flux

Electron
Muon
Neutrino
Muon AntiNeutrino

Electron
Anti-Neutrino
SuperKDetector

27 October 2016

Pions

John Learned at Tohoku Forum for Creativity

Nucleus (air)Super-Kamiokande

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Primary Cosmic RayAtmospheric Neutrino Anomaly
Super-Kamiokandeνeνµνµfrom below

only half of themuon neutrinos
from the far
side of earth

19νeJohn Learned at Tohoku Forum for Creativity

27 October 2016

from above

Phys. Rev. Lett. 81,1562 (1998).

Nobel Prize 2015

John Learned at Tohoku Forum for Creativity

SuperK neutrino
oscillations paper
now most cited
paper in history ofexperimental
particle physics

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νμ-ντ

27 October 2016

MC No-Osc

50%

50%

Atmospheric Neutrinos:
m 32 − m22 = 2 ´ 10 −3 eV 2Solar Neutrinos:

70%

35%

35%

m2 − m2 = 7 × 10 − 5 eV 22115%15%

Mixings peculiarly large,
No theoretical model

John Learned at Tohoku Forum for Creativity

30%

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Differences of neutrino
masses deduced fromoscillation experiments.

27 October 2016

Neutrino Mass and Composition

27 October 2016
John Learned at Tohoku Forum for Creativity
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Neutrinos
may play
crucialrole in thegenesis ofexcess
matter overanti-matterin theuniverse…
Hence weare here!

Matter Inventory of the Universe
Copernicusn !

Dark
MatterNeutrinos
min. 0.1%
max. 6%23

Normal Matter(of which ca.
10% luminous)

John Learned at Tohoku Forum for Creativity

27 October 2016

Dark Energy(Cosmological Constant)

IMB event 33160, 39 MeV
Seconds after first Event

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John Learned at Tohoku Forum for Creativity

Energy in MeV

27 October 2016

Neutrino Signal from Supernova 1987A

And, the Fluorine inyour toothpaste, forexample.

John Learned at Tohoku Forum for Creativity

The r-process insupernovae is thought
to be the main sourceof heavy elements.

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Neutrinos condition
the neutron bathin which the atoms
accrete mass.

27 October 2016

Neutrinos Involved in Making the Heavy Elements

26John Learned at Tohoku Forum for Creativity

27 October 2016

KamLAND sees neutrinos from Japan (and Korea)

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John Learned at Tohoku Forum for Creativity

27 October 2016

KamLAND Observes Neutrino Oscllations

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John Learned at Tohoku Forum for Creativity

27 October 2016

KamLAND Neutrinos from the earth“GeoNeutrinos”

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John Learned at Tohoku Forum for Creativity

27 October 2016

Moving on to the Big Picture
and the Future needs

Rejuvenated Soon?
KamLAND
SuperK
Borexino
Probable (my view)
HyperK, HKK
DUNE (10KT)
JinPing
INO
Also discussed• USA (“Theia Project”)• Europe LAGUNA (LENA)John Learned at Tohoku Forum for Creativity

Under Construction
SNO+JUNO

30Motivations (~in energy order):• Geoneutrinos• Neutrinoless bb decay• Solar Neutrinos (HeP, CNO…)• RAA and Reactor Spectrum Problems• Search for Sterile Neutrinos• Relic SN Neutrinos• Supernova Neutrinos• Indirect DM Searches• Other anomalies (LSND, MBOONE)• Nuclear Counter-Proliferation• Proton Decay Search• Long-Baseline Oscillations• Hierarchy• CP violation• Atmospheric Neutrinos• Earth Tomography• Cosmic Neutrinos (>100 TeV, >1PeV)

27 October 2016

The Next Challenges in Big Neutrino Detectors:
50 KT LS - 600 KT WC Detectors?

World Nu Community cannot afford Many >$500M Detectors

John Learned at Tohoku Forum for Creativity

We must join together to move forwards.
Theia? SuperKamLAND?

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Several Areas Needing Improvements- Lower thresholds… big detectors reaching ~1-2 MeVMore Pixelation (~1m -> few cm)
Timing (<100 ps)
Better Scintillator or WBLS (more light, long atten)
Great Cleanliness (Borexino or better)
Lower CR backgrounds by going deeper than 2KMwe

27 October 2016

New Physics Challenges, and New Detectors- Directionality (even a little is good at few MeV)
- Better particle ID in LB experiments (back reconstruction)
Not all are possible in one type of detector

What is missing in the world mix?

JGL’s current favorite prospect:
50 KT LS Theia in HomestakeNow discuss some issues related to such development.
Photodetectors are prominent need, not discussed here.

John Learned at Tohoku Forum for Creativity

M > 20kt withThreshold ~ 1 MeV
Depth >>2 kmwe
An accelerator beam pointed at it32

We need a detector with

27 October 2016

Assuming extended IceCube and KM3 at high energy +HyperK + SNO+ and JUNO and Jinping…

2009 Realization that Liquid Scint Detector Can Reconstruct EventsFirst light yields topology.

John Learned at FROST, Mainz

21 October 2016

Snapshot of the Fermat Surface for a Single Muon-likeTrack

TrackHuygens

Incoherent sum
coincident with
Cherenkov surface:Not polarized!
J.G. Learned, asXiv:0902.4009

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wavelets

Sakai thesis, 201634

John Learned at FROST, Mainz

21 October 2016

Fast and Simple Start to Reconstruction

Fit to 14 Neutrinos in KamLAND from J-Parc

Not official KL result yet

Sakai Thesis

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John Learned at FROST, Mainz

21 October 2016

Tag pure beam neutrinos due to having spill times

John Learned at FROST, Mainz

21 October 2016

A Simple Ellipticity Particle ID

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Probably can do much better in future

Sakai Thesis

Competitive DM Results from This Technique<1KT KL
22KT SK

Sakai Thesis

Not official KL Results, yet

37John Learned at FROST, Mainz

21 October 2016

Sakai Used Back-Propogationtion in KamLANDto seek Dark Matter Annihilation Neutrinos

38John Learned at Tohoku Forum for Creativity

27 October 2016

From Sebastian Lorenz’s talk at FROST, Mainz
10/22/2016

John Learned at Tohoku Forum for Creativity

in a single large deep scintillation detector

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We can have low threshold (MeV)
and we can achieve cm scale resolution at
higher energies (GeV)
to cover ahuge range in energy
andgreat reach in physics

27 October 2016

What is the point?

2.2 liter scintillator

Contain positron, lose gammas•Do imaging with fast timing, notoptics (time reversal imaging).

•Get some neutrino directionality
between positron origin andneutron capture point.

•Reject noise on the fly; noshielding needed (if far fromreactor)•4 x 6 MCP (x64 pixels each) fast(<100 ps) pixel detectors on
surrounding faces•~10/day anti-neutrino interactions(inverse beta decay signature)from reactor.

•Data taken at NIST, being
analyzed at present

21 October 2016•

John Learned at FROST, Mainz

Fast digitizing electronics (x6)

Small portable 2.2 liter
scintillating cube with neutron
capture doping.

40MiniTimeCube Smalland Directional
Inverse Beta Detector•21 October 2016

Fitting the Positron Track in mTC

Glenn Jocher, Ultralytics

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Positron track,and fitting to it

John Learned at FROST, Mainz

GEANT Event in mTC

NuLat a new type of 3D pixelated detector

Lithiated plastic cubes now available
Alternate design for large version with LS

NB, log scale

John Learned at Tohoku Forum for Creativity

6 PMTs get coincident, strong light

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Light transmitted largely to 3 directions

27 October 2016

Stack of optically isolated scintillating cubes

Reconstructing 3D Energy Deposition in NuLat

Reconstructed

Not the case in 2D or 1 D detectors….
Very importnat in identifying events and eliminating backgrounds

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John Learned at Tohoku Forum for Creativity

Truth

27 October 2016

Allows breaking multi-dimensional degeneracies

NuLat as a reactor neutrino detector

John Learned at Tohoku Forum for Creativity

27 October 2016

Directionality

44• Reactor power cycles
and fuel composition• New tool in nonproliferation arsenal• Detection of special
nuclear materials• NuLat whitepaper:arXiv:1501.06935• See talk at AppliedAntineutrino Physics
2015John Learned at Tohoku Forum for Creativity

A 5×5×5 ROL with 6Li-loaded scintillator
Contract with Eljen for 130 cubes
Instrumented with 150 PMTs, Spring 2017
Demonstrate reactor monitoring– Deploy at commercial power plant• Measure backgrounds for NuLat– Deploy at NIST in NuLat shielding45••••

27 October 2016

NuLat Demonstrator Being Assembled Now

Same location as mTC
5 m from coreSpring 2017
NuLat at NSBR, NIST

NuLat at NSBR, NIST46

Plan to take to NISTJohn Learned at Tohoku Forum for Creativity27 October 2016

NuLat at a 20MW Reactor

Gamma-induced false prompt events– Multiple Compton scattering: Energy outside of vertex– Accept 0.2 MeV < E < 1.0 MeV– This alone removes ~ 60% of gammas

AcceptancewindowJHU APL

Acceptancewindow

2 MeV
positrons

47Gammas

PSD for background rejections

A778, 126 (2015)• Tail-to-total method

JHU APL– Different dE/dx ⇒different scintillator
response
N. Cherepy, et al., NIM

M. J. I. Balmer, et al., NIM
A788, 146 (2015)48• Pulse shapediscrimination

SummaryCampaigns progressing for hierarchy, lowest mass, CP violation
A few mysteries and many challenges remain
New detection techniques are being developed… only discussed
two which we have been exploring... (mTC and NuLat)
Seems to be growing international desire for a huge scintillation
detector at great depth, low threshold, and 10x existing size
Solution: Theia? SuperKamLAND? Other?

John Learned at Tohoku Forum for Creativity

We have a good 3 neutrino model

27 October 2016

Neutrino studies are mature

49

Join the fun and stay tuned

50

John Learned at Tohoku Forum for Creativity

27 October 2016