International Workshop：Neutrino Research and Thermal Evolution of the Earth @ Tohoku University, October 2016

Prospects for Neutrino
Oscillation Tomography

Carsten Rott (SKKU)
and Akimichi Taketa (ERI)

rott @skku. edu
nospamnospamOct 25-27, 2016

Outline• Motivation• Methodology of Neutrino
Oscillation Tomography• Neutrino Detectors and
IceCube / PINGU• Prospects for Neutrino

Oscillation Tomography• Conclusions
Carsten Rott2

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Motivation

Carsten Rott3

International Workshop：Neutrino Research and ThermalEvolution of the Earth - Tohoku University Oct 2016

Motivation (Particle Physics

Geo-science)• What can neutrino detectors do for Solid Earth Science ?
• Muon Radiography• Atm. airshower muon absorption• Geo-neutrinos• Low-energy neutrino detection from nuclear decays• Neutrino absorption tomography• Atm. air shower high-energy neutrino absorption• Neutrino oscillation tomography• Atm. air shower neutrino oscillations

Geo-neutrinos

Neutrino absorption
tomography

Neutrino oscillation
tomography talkU and Th geo-νKamLANDsihTIceCube
IceCubeCarsten Rott

IceCube

4International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Motivation - Methodology• The Earth matter density

profile can be determinedfrom seismic measurements• Matter induced neutrino

oscillation effects however
dependent on the electrondensity• Given a matter density profile

the “average” composition (orZ/A) along the neutrino pathcan be determined using
neutrino signals (Oscillation
tomography)

corresponding zenith angles for boundaries
inner core θν <169º (cos θν < -0.98)
outer core θν <147º (cos θν < -0.84)

Electron density in core
Yc=electron/nucleons
Carsten Rott5International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Motivation - Neutrino Oscillation Tomography• New Method tounderstand inner Earth• Inner Earth Composition• Light elements in theNature Geoscience;
Volume: 4, 647–651 (2011)

outer core ?

• Understand theGeodynamo• Lower mantle density
and anisotropy

1st Tomography Workshop @ ERI Jan 2016

• Apply neutrino physics toEarth Science

Carsten Rott6International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Neutrino Oscillation Tomography

Carsten Rott

7International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Rott & Taketa 2015

Three flavour + matter effects

Oscillograms
Increasing density

Core Mantle Boundary -0.84

verticalCarsten Rotthorizontal
9International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

How to read an oscillograms
Increasing density

Outer core boundary -0.84

An example ...
0°Θz=~0.9z=
5-0 142.80 °

~16sΘ

cos

cosΘz=-1.0180°(A) 4GeV(B) 3GeV

co4°
11~ .40-0z=
Θso(A) 4GeVxcA muon neutrino created at (A)with energy 4GeV has a ~90%
chance to be detected as suchafter traversing the Earth(B) 3GeVx

A muon neutrino created at (B)with energy 3GeV has a ~40%
chance to be detected as suchafter traversing the EarthverticalCarsten Rotthorizontal
10International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Oscillogram (“normal” electron density)
Increasing densityOuter core boundary -0.84

verticalCarsten Rotthorizontal
11International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Oscillogram (enhance electron density)
Increasing density

Outer core boundary -0.84

Change Earth coreelectron density by
10% to visualizechange in survival
probability
Most significant changes
are seen in an energy
range of 2-10GeV andfor neutrinos passing
through the coreregion(cosθ < -0.84)

verticalCarsten Rotthorizontal
12International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Rott & Taketa Scientific Reports (2015)

Pure Fe

Carsten RottOscillograms

Fe + 2wt% H13

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Neutrino Source and Detectors
Atmospheric neutrinos are a natural steadysource of muon and electron neutrinos at theenergy range relevant for neutrino oscillation
tomography

IceCube Collaboration Phys. Rev. Lett. 110 (2013) 151105 / 1212.4760v2

cosmic rays
air shower

IceCube νeneutrinos±±• p + A → π (K ) + other hadrons• π →μ ν →e ν ν ν+++μCarsten Rotte μ μ14

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Atmospheric Neutrinos
Atmospheric neutrinos are a natural steadysource of muon and electron neutrinos at theenergy range relevant for neutrino oscillation
tomography

Super-Kamiokande Phys. Rev. D 94, 052001 (2016) [arXiv:1510.08127]

cosmic rays
air showerneutrinos±±• p + A → π (K ) + other hadrons• π →μ ν →e ν ν ν+++μCarsten Rotte μ μ15

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Neutrino Source and Detectors
Atmospheric neutrinos are a natural steadysource of muon and electron neutrinos at theenergy range relevant for neutrino oscillation
tomography

cosmic rays

• Detector requirements for neutrino oscillation tomography• good energy resolution fully contained events, good
optical coverage• good angular resolution

precise timing, good opticalcoverage• large volume

air shower

acquire high statistics neutrino sample

Large Volume Water/Ice Cherenkov Telescope

neutrinos±±• p + A → π (K ) + other hadrons• π →μ ν →e ν ν ν+++μCarsten Rotte μ μ16

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

The IceCube Neutrino Telescope

Carsten Rott17

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Laboratory at the South
Pole

Geographic South PoleAmundsen Scott
South Pole
Station
1 km

Road tow

yakiw

orkebuIceCS
Carsten Rott18

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

The IceCube Neutrino Telescope• Gigaton Neutrino Detector at
the Geographic South Pole

Digital optical modules• 5160
distributed over 86 strings

Strings

Dataset12005-2006

92006-2007

222007-2008

4059

2008-20092009-2010

73 + 6

2010-2011

78 + 82011 - .....

in December 2010,• Completed
start of data taking with full
detector May 2011acquired during the• Data
construction phase has been

EThr ~ 100 GeV

analyzed•N e u t r i n o s a re i d e n t i fi e dt h ro u g h C h e re n kov l i g h temission from secondar yparticles produced in theneutrino interaction with theiceCarsten Rott

EThr ~ 10 GeVμνμ19International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

IceCube Observations
Scientific Scope• ASTROPHYSICS• point sources of ν’s (SNR, AGN … ), extended
sources• transients (GRBs, AGN flares …)• diffuse fluxes of ν’s (all sky, cosmogenic, galactic
plane …)

• COSMIC RAY PHYSICS• energy spectrum around ”knee”, composition,
anisotropy• DARK MATTER• indirect searches (Earth, Sun, galactic center/halo)• EXOTIC SOURCES OF ν’S• magnetic monopoles• PARTICLE PHYSICS• ν oscillations, sterile ν’s• charm in CR interactions• violation of Lorentz invariance• SUPERNOVAE (galactic/LMC)• GLACIOLOGY & EARTH SCIENCE
Carsten Rott20

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Neutrino Oscillations in IceCube

Carsten Rott21

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Neutrino Oscillations• Neutrinos come in three

Sourcedifferent flavors: νe,νμ,ντ• A neutrino created as one

W+Detector+μνlong journey

flavor can change into a
different flavor

τ+cc• This phenomenon (neutrinooscillations) depends on theenergy of the neutrino andthe distance traveled• It further depends on the“potential” the neutrino
travels through

Carsten Rottnoi
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International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

IceCube Neutrino Oscillations

IceCube Phys. Rev.D91:072004 (2015)

Carsten Rott23

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

PINGU

Carsten Rott

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International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

IceCube PINGU Collaboration arXiv:1401.2046

PINGU - Precision IceCube Next GenerationUpgrade• PINGU upgrade plana volume of about• Instrument
5MT with 20-26 strings© [2011] The Pygos GroupNew PINGU Geometry

PRELIMINARY• Rely on well established drilling
technology and photo sensors• Create platform for calibration

program and test technologies for
future detectors• Physics Goals:
measurements of• Precision
neutrino oscillations (masshierarchy, ...)

low mass dark matter• Testmodels

Compared to 40 string geometry
1. One less drilling/deployment season
2. Fewer holes drilled (saves fuel)3. Fewer holes and one less season
means we can refurbish drill rather thanbuild a new one.

Updated LOI later this year
Proposal in preparation
Carsten Rott25

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

PINGU Detector Performance
Muon Neutrino Angular Resolution

Muon Neutrino Energy Resolution• PINGU performance using existing algorithms for IceCube• More computationally intensive algorithms are expected tofurther improve performance

Carsten Rott26

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Parameterize Detector Performance
Muon Neutrino Energy Resolution

Muon Neutrino Angular Resolution

We adopt a value of
α=0.2 as benchmark

We adopt β=0.25 asbenchmark

Carsten Rott27

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Rott & Taketa 2015

Sensitivity• A few years of
PINGU data
would yield afew 10MTyrs• Probe ~2-4wt% hydrogen• Reject extreme
corecomposition
modelsCarsten Rott28

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

How can we increase sensitivity ?

• Dependence on the angular resolution
and energy resolution:

100908070
6050

Carsten Rott

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International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Neutrino Tomography PINGUPINGU LOI arxiv:1401.2046
In PINGU we expect approximately 30000 upward-going neutrinos per year, withmany coming from the energy region between 5–10 GeV.

Carsten Rott30

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

PINGU LOI arxiv:1401.2046

PINGU Sensitivity

Parametric: Ai= 0.25 and
Ai= 0.10

Baseline:

to be updated with full PINGU detector simulation
Carsten Rott

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International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

KEK Preprint 2016-21
ICRR-Report-701-2016-1
https://lib-extopc.kek.jp/preprints/PDF/2016/1627/1627021.pdf

Hyper-K Sensitivity

Sensitivity of the electron density of the Earth’s core at HyperK with 10 Megaton-years

K. Hagiwara, N. Okamura, K. Senda Phys.Lett. B637 (2006) 266-273• Prospects for hosting second HyperK tank in Korea … stay tuned

KPS 2016 Fall Meeting
Kimdaejung Convention Center, Gwangju
Oct 19 (Wed) -Oct 21 (Fri)

Next: Nov. 21-22 2016: 1st International T2HKK workshop at SNU
Carsten Rott32

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Neutrino Oscillation Tomography Road AheadGoals

Detectors(1) Demonstratefeasibility of neutrinooscillation tomography• Now• Feasibility of very large volume
neutrino detectors has been
demonstrated (IceCube, ...)

• High-precision neutrino detectors(2) Perform firstneutrino oscillation
tomographymeasurement

demonstrated (Super-K, ...)• Near future• ~1MT detectors with 2-10GeV
neutrino sensitivity (PINGU,ORCA, Hyper-K, Baikal-GVD(?) ...)(3) Distinguish specific
Earth composition
models via oscillation
tomography
Carsten Rott• More distant future• >>10MT detector with 2-10GeV

neutrino sensitivity (new detector,augmented PINGU or ORCA)

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International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Rott & Taketa 2015

Distinguishing Outer core models
Hydrogen content (wt%)

Carsten Rott

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International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Other prospects

Carsten Rott

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International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

W. Winter Nucl.Phys. B908 (2016) 250-267

Density measurements

Excellent sensitivities to the lower mantle
density and give a robust lower bound on
the outer core densityPercentage errors achievable with 10 years of data

PINGU and ORCA can provide complementary
information due to different locations. Seismic
measurements show irregular wave propagation
zones in the lower mantle
Carsten Rott36

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Garnero, McNamara, Shim Nature Geoscience 9, 481–489 (2016)

Lower mantle

http://www.nature.com/ngeo/journal/v9/n7/pdf/ngeo2733.pdf• Continent-sized anomalous zones with low

seismic velocity at the base of Earth's mantle• Large low shear velocity provinces (LLSVP) up to
1,200km above CMB

Muon neutrino survival probability
Z/A=0.4957
Z/A=0.5007

Difference• Tomography with multiple detectors

See poster from Jonghyun Kim

Carsten Rott37

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Conclusions• Neutrino oscillation tomography is a novel method to better
understand the Earth interior• Measure the Earth interior composition• Extremely sensitivity to hydrogen• Sensitivity to lower mantle density / LLSVP• PINGU/ORCA/Hyper-K could put first constrain on the EarthCore water content within first few years of operations (givennormal mass hierarchy)• Next-generation, large volume detectors are needed to distinguishspecific core models• very large - high statistics sample• good energy resolution and angular resolutions
Carsten Rott38

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Thank you !

Carsten Rott39

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Rott & Taketa 2015

Uncertainty due to Earth model

Uncertainty due to theEarth mass density
profile is negligible
PREM500 - Dziewonski, A. & Anderson, D. Preliminary reference Earth model. Physics of the Earthand Planetary Interiors 25, 297–356 (1981).
AK135 - Kennett, B., Engdahl, E. & Buland, R. Constraints on seismic velocities in the earth fromtravel times. Geophysical Journal International 122, 108–124 (1995).
PREM-A - Dziewonski, A., Hales, A. & Lapwood, E. Parametrically simple earth models consistent
with geophysical data. Physics of the Earth and Planetary Interiors 10, 12–48 (1975).

Carsten Rott40

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Z/A ratios
ElementHydrogen
CarbonOxygenMagnesium
SiliconSulfur
Iron
NickelHCO
Mg
SiSFeNiZ
168
12141626
28

A
1.008
12.01115.99924.30528.08532.06
55.84558.693Z - Atomic Number

Z/A
0.99210.49950.5
0.49370.49850.49910.46560.4771A - Atomic Mass

• Z/A ratios
Carsten Rott41

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Rott & Taketa 2015

Statistical Method• Generate template for expected number of events and their distribution inenergy and zenith angle for two different outer core composition models(Model A and Model B)• Assume one composition and calculate likelihood with respect to A and B andtake ratio• Perform pseudo experiments• Distribution tells us the probability to distinguish the two models if themeasurement were to be done

Carsten Rott42

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016

Rott & Taketa 2015

Uncertainty due to mixing parameters

Use the best fit oscillation parameters and their uncertainties of:
Capozzi, F. et al. Status of three-neutrino oscillation parameters, circa
2013. Physical Review D 89, 093018 (2014).
Carsten Rott43

International Workshop：Neutrino Research and Thermal
Evolution of the Earth - Tohoku University Oct 2016