Neutrino Oscillation Tomography (and Neutrino Absorption Tomography) - - PowerPoint PPT Presentation

Neutrino Oscillation Tomography

(and Neutrino Absorption Tomography)

(and Neutrino Parametric-Refraction Tomography) Sanshiro Enomoto University of Washington

CIDER Geoneutrino Working Group Meeting, UCSB, 1 July 2014

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Everything Shown Here was Taken from:

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and references in there

Atmospheric Neutrinos

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Ice Cube at South Pole Super-Kamiokande in Japan

40 m 1000 m 0.02 km3 1 km3 50 kt primary cosmic ray (proton) (10 MeV ~ 100 GeV) (100 GeV ~ )

X N + → +

−

µ ν µ

Detection by Charged-Current Deep-Core

(10 GeV ~ )

Atmospheric Neutrinos and Neutrino Oscillation

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Survival Probability Zenith Angle ⇒ Distance Energy (GeV)

10 GeV

      ⋅ × ≈ →

−

GeV / km / 10 3 sin

• 1

) (

3 2

E L P

µ µ

ν ν Probability of detecting νμ after distance L

µ

ν

τ

ν

e

ν

(w/o matter effects)

Oscillation Tomography using Matter Effect

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• D. R. Grant, Neutrino 2014

Neutrino oscillation is affected by Electron Density

Neutrino Oscillation though Earth

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Hierarchy Normal ) ( − →

µ µ

ν ν P

IH ) ( ~ − →

µ µ

ν ν P

Hierarchy Inverted ) ( − →

µ µ

ν ν P

NH ) ( ~ − →

µ µ

ν ν P

10 GeV cos(zenith angle) cos(zenith angle) Survival Probability Energy (GeV) Energy (GeV) Survival Probability Core

Neutrino Oscillation though Earth

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Hierarchy Normal ) ( − →

µ µ

ν ν P

IH ) ( ~ − →

µ µ

ν ν P

Hierarchy Inverted ) ( − →

µ µ

ν ν P

NH ) ( ~ − →

µ µ

ν ν P

10 GeV Core MSW Resonance

• n θ13

(adiabatic) cos(zenith angle) cos(zenith angle) Energy (GeV) Energy (GeV) Survival Probability Survival Probability Parametric Enhancement (non-adiabatic) &

Neutrino Oscillation though Earth

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Hierarchy Normal ) ( − →

µ µ

ν ν P

IH ) ( ~ − →

µ µ

ν ν P

Hierarchy Inverted ) ( − →

µ µ

ν ν P

NH ) ( ~ − →

µ µ

ν ν P

10 GeV Core cos(zenith angle) cos(zenith angle) Energy (GeV) Energy (GeV) Survival Probability Survival Probability MSW Resonance

• n θ13

(adiabatic) Parametric Enhancement (non-adiabatic) &

Neutrino Oscillation though Earth

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Hierarchy Normal ) ( − →

µ µ

ν ν P

IH ) ( ~ − →

µ µ

ν ν P

Hierarchy Inverted ) ( − →

µ µ

ν ν P

NH ) ( ~ − →

µ µ

ν ν P

10 GeV Core cos(zenith angle) cos(zenith angle) Energy (GeV) Energy (GeV) Survival Probability Survival Probability MSW Resonance

• n θ13

(adiabatic) Parametric Enhancement (non-adiabatic) &

Sensitivity to Core Z/A

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Iron Core (Z/A=0.4656) Pyrolite (Z/A=0.4957) Normal Hierarchy

Z/A Ratio:

Hydrogen: 1 Light Elements: 0.5 Mantle (Pyrolite): 0.4957 Iron: 0.4656 6.5% difference

If Density is known, electron density gives Z/A ratio

Wish List

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 Gigantic Detector (~ Mega ton)  Dense Detector (~1 GeV threshold)  Good Energy and Angular Sensitivity  Normal Hierarchy Preferred 

(antineutrino cross-section is smaller)

• Ice-Cube is too sparse (Deep-Core detects E >10GeV)
• Super-Kamiokande is too small (total 50 k-ton)

Neutrino Charged-Current Cross-section Atmospheric Neutrino Flux

PINGU: Ice-Cube Upgrade for Lower Energy

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arXiv:1401.2046 (9 Jan 2014)

 ~3 M-ton effective volume  x20 photo cathode density  sensitivity downto few GeV $100M, ready in ~5 years

Hyper-Kamiokande (Super-K successor)

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arXiv:1109.3262 (15 Sep 2011)

 0.99 M-ton  20% photo coverage  few MeV threshold

PINGU: Sensitivity to Core Z/A

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Iron Core Pyrolite

Normal Hierarchy

Difference in νμ Survival Probability

• PINGU volume (40 string)
• PINGU energy resolution (ΔE/E = 0.33)
• PINGU angular resolution (Δθ=15°)
• PINGU systematic errors

Difference in Number of Events

Normal Hierarchy Inverted Hierarchy

0.45

• 0.45

0.20

• 0.20

1 yr 1 yr

PINGU: Sensitivity to Core Z/A

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Fe: 0.4656 Pyrolite: 0.4957 (+6.5% to all-Fe)

PINGU 5 yr

PINGU: Sensitivity to Core Z/A

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Fe: 0.4656 Pyrolite: 0.4957 (+6.5% to all-Fe)

PINGU 5 yr

Fe + H (1 wt%): 0.4709 (+1.0% to all-Fe)

PINGU: Sensitivity to Core Z/A

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 Pyrolite model can be tested at 1σ after 5 years (Normal Hierarchy)  Inverted Hierarchy will limit the sensitivity to ~20%, “because antineutrino cross-section is half of neutrinos”...  Dependence on θ13 value is small  Better energy resolution will largely improve the sensitivity

Hyper-Kamiokande might do it better

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Hyper-Kamiokande  Better energy and angular resolutions  νe channel usable

• Smaller active volume??

PINGU

HK: 1 M-ton water cherenkov

50 m

Low-energy sensitivity increases effective volume

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Hyper-Kamiokande Letter of Intent arXiv:1109.3262 (15 Sep 2011)

PINGU

Partially-Contained Event μ νμ

Neutrino Absorption Tomography

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Kotoyo Hoshina, AGU Fall 2012

Neutrino Absorption Tomography

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Kotoyo Hoshina, AGU Fall 2012

Neutrino Absorption Tomography

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Kotoyo Hoshina, AGU Fall 2012

Neutrino Absorption Tomography

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Kotoyo Hoshina, AGU Fall 2012

Appendix: Parametric Enhancement is Sensitive to CMB?

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10 GeV Core cos(zenith angle) Energy (GeV) Survival Probability MSW Resonance

• n θ13

(adiabatic) Parametric Enhancement (non-adiabatic) & Transition probability depends on structures of density step

Summary

• Neutrino Oscillation Tomography

– Direct measurement of core composition – Uses oscillation matter effect (MSW) at 1~10 GeV – PINGU will measure Z/A at ~8% accuracy (NH case), possibly better – Inverted hierarchy will limit the sensitivity to ~20% – Hyper-Kamiokande might be able to do it better – ORCA (KM3NeT, 1.8 M-ton in sea water) can do the same?

• Neutrino Absorption Tomography

– Direct measurement of core density – Uses neutrino absorption at ~10 TeV – 10 yr Ice-Cube will discriminate core from mantle

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Back Up

Photo Coverage vs Energy Threshold

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• D. R. Grant, Neutrino 2014

MSW Resonance

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antineutrinos neutrinos

Atmospheric Neutrino Composition

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• M. Honda et al, Phys Rev D 70, 043008 (2004)