Neutrinos: Ghostparticles of the UniverseGeorg Raffelt, MPI Physics, Munich Physics Colloquium, UNSW, Sydney, 4 March 2014 Neutrinos –Neutrinos Ghost Particles of the Universe Ghost

Georg Raffelt, MPI Physics, Munich Physics Colloquium, UNSW, Sydney, 4 March 2014

Neutrinos – Ghost Particles of the Universe

Neutrinos Ghost Particles of the Universe

Georg G. Raffelt

Max-Planck-Institut für Physik, München, Germany


Neutron

Proton

Periodic System of Elementary Particles

Quarks Leptons

Charge -1/3

Down

Charge -1

Electron

Charge 0

e-Neutrino ne e d

Charge +2/3

Up u


Neutron

Proton

Gravitation (Gravitons?)

Weak Interaction (W and Z Bosons)

Periodic System of Elementary Particles

Electromagnetic Interaction (Photon)

Strong Interaction (8 Gluons)

Down

Strange

Bottom

Electron

Muon

Tau

e-Neutrino

m-Neutrino

t-Neutrino nt

nm

ne e

m

t

d

s

b

1st Family

2nd Family

3rd Family

Up

Charm

Top

u

c

t

Quarks Leptons

Charge -1/3

Down

Charge -1

Electron

Charge 0

e-Neutrino ne e d

Charge +2/3

Up u

Higgs

Georg Raffelt, MPI Physics, Munich Colloquium, UNSW, Sydney, 4 March 2014

Where do Neutrinos Appear in Nature?

Nuclear Reactors

Particle Accelerators

Earth Atmosphere (Cosmic Rays)

Earth Crust (Natural Radioactivity)

Sun

Supernovae (Stellar Collapse) SN 1987A

Cosmic Big Bang (Today 330 n/cm3) Indirect Evidence

Astrophysical Accelerators


Neutrinos from the Sun

Reaction- chains

Energy 26.7 MeV

Helium

Solar radiation: 98 % light 2 % neutrinos At Earth 66 billion neutrinos/cm2 sec

Hans Bethe (1906-2005, Nobel prize 1967)

Thermonuclear reaction chains (1938)


Sun Glasses for Neutrinos?

8.3 light minutes

Several light years of lead needed to shield solar neutrinos

Bethe & Peierls 1934: … this evidently means that one will never be able to observe a neutrino.


First Detection (1954 – 1956)

Fred Reines (1918 – 1998) Nobel prize 1995

Clyde Cowan (1919 – 1974) Detector prototype

Anti-Electron

Neutrinos

from

Hanford

Nuclear Reactor

3 Gammas

in coincidence 𝝂𝐞 p

n Cd

e+ e−

g

g

g


First Measurement of Solar Neutrinos

600 tons of Perchloroethylene

Homestake solar neutrino observatory (1967–2002)

Inverse beta decay of chlorine


2002 Physics Nobel Prize for Neutrino Astronomy

Ray Davis Jr. (1914–2006)

Masatoshi Koshiba (*1926)

“for pioneering contributions to astrophysics, in particular for the detection of cosmic neutrinos”


Cherenkov Effect

Water

Elastic scattering or CC reaction

Light

Light

Cherenkov Ring

Electron or Muon (Charged Particle)


Super-Kamiokande Neutrino Detector (Since 1996)

42 m

39.3 m

Super-Kamiokande: Sun in the Light of Neutrinos

Super-Kamiokande: Sun in the Light of Neutrinos

ca. 60,000 solar neutrinos measured in Super-K (1996–2012)


Average (1970-1994) 2.56 0.16stat 0.16sys SNU (SNU = Solar Neutrino Unit = 1 Absorption / sec / 1036 Atoms)

Theoretical Prediction 6-9 SNU “Solar Neutrino Problem” since 1968

Results of Chlorine Experiment (Homestake)

ApJ 496:505, 1998

Average Rate

Theoretical Expectation


Neutrino Flavor Oscillations

Bruno Pontecorvo (1913–1993)

Invented nu oscillations

Two-flavor mixing

Each mass eigenstate propagates as 𝑒i𝑝𝑧

with 𝑝 = 𝐸2 −𝑚2 ≈ 𝐸 −𝑚2 2𝐸

Phase difference 𝛿𝑚2

2𝐸𝑧 implies flavor oscillations

Oscillation Length

sin2(2𝜃)

Probability 𝜈𝑒 → 𝜈𝜇

z

𝜈𝑒𝜈𝜇=cos 𝜃 sin 𝜃−sin 𝜃 cos 𝜃

𝜈1𝜈2

4𝜋𝐸

𝛿𝑚2= 2.5 m

𝐸

MeV eV

𝛿𝑚

2


Oscillation of Reactor Neutrinos at KamLAND (Japan)

Oscillation pattern for anti-electron neutrinos from Japanese power reactors as a function of L/E

KamLAND Scintillator detector (1000 t)


Atmospheric Neutrino Oscillations

Atmospheric neutrino oscillations show characteristic L/E variation


Long-Baseline (LBL) Experiments

K2K Experiment (KEK to Kamiokande) and then other LBL experiments measure precise neutrino oscillation parameters.


Q13 from Reactor Experiments (2012)

4MeV ͞ne

sin22θ13 = 0.089 ± 0.010 (stat) ± 0.005 (syst)

0.113 ± 0.013 (stat) ± 0.019 (syst)

Daya Bay (China)

Reno (Korea)

0.086 ± 0.041 (stat) ± 0.030 (syst) Double Chooz (Europe)


v

Three-Flavor Neutrino Parameters

𝜈𝑒𝜈𝜇𝜈𝜏=1 0 00 𝑐23 𝑠230 −𝑠23 𝑐23

𝑐13 0 𝑒−𝑖𝛿𝑠130 1 0−𝑒𝑖𝛿𝑠13 0 𝑐13

𝑐12 𝑠12 0−𝑠12 𝑐12 00 0 1

1 0 0

0 𝑒𝑖𝛼22 0

0 0 𝑒𝑖𝛼32

𝜈1𝜈2𝜈3

Three mixing angles 𝜃12, 𝜃13, 𝜃23 (Euler angles for 3D rotation), 𝑐𝑖𝑗 = cos 𝜃𝑖𝑗,

a CP-violating “Dirac phase” 𝛿, and two “Majorana phases” 𝛼2 and 𝛼3

39∘ < 𝜃23 < 53∘ 7∘ < 𝜃13 < 11

∘ 33∘ < 𝜃12 < 37∘ Relevant for

0n2b decay Atmospheric/LBL-Beams Reactor Solar/KamLAND

m e t

m e t

m t

1 Sun

Normal

2

3

Atmosphere

m e t

m e t

m t

1 Sun

Inverted

2

3

Atmosphere

Δ𝑚2 72–80 meV2

2180–2640 meV2

Tasks and Open Questions • Precision for all angles

• CP-violating phase d ? • Mass ordering ? (normal vs inverted) • Absolute masses ? (hierarchical vs degenerate) • Dirac or Majorana ?


Antineutrino Oscillations Different from Neutrinos?

Dirac phase causes different 3-flavor oscillations for neutrinos and antineutrinos

Distance [1000 km] for E = 1 GeV

𝜈𝑒 → 𝜈𝑒 same as 𝜈𝑒 → 𝜈𝑒

𝜈𝑒 → 𝜈𝜇

𝜈𝑒 → 𝜈𝜇

𝝂𝐞 = 𝑐12𝑐13 𝝂𝟏 + 𝑠12𝑐13 𝝂𝟐 + 𝑠13𝑒−𝑖 𝛿 𝝂𝟑

𝝂𝐞 = 𝑐12𝑐13 𝝂𝟏 + 𝑠12𝑐13 𝝂𝟐 + 𝑠13𝑒+𝑖 𝛿 𝝂𝟑


Neutrino Carabiner Named for a subatomic particle with almost zero mass, …

Greek “nu”


Neutrino Carabiner Named for a subatomic particle with almost zero mass, …

Greek “nu” Now also in color


“Weighing” Neutrinos with KATRIN

• Sensitive to common mass scale m for all flavors because of small mass differences from oscillations

• Best limit from Mainz und Troitsk m < 2.2 eV (95% CL)

• KATRIN can reach 0.2 eV

• Under construction

• Data taking to begin 2015/16

• http://www.katrin.kit.edu


KATRIN Ante Portas (25 Nov 2006)


Weighing Neutrinos with the Universe


Cosmological Limit on Neutrino Masses

JETP Lett. 4 (1966) 120

Cosmic neutrino “sea” ~112 cm-3 neutrinos + anti-neutrinos per flavor

Ω𝜈ℎ2 =

𝑚𝜈93 eV< 0.23

For all

stable flavors ∑𝑚𝜈 ≲ 20 eV


What is wrong with neutrino dark matter?

Galactic Phase Space (“Tremaine-Gunn-Limit”)

Maximum mass density of a degenerate Fermi gas

𝜌max = 𝑚𝜈𝑝max3

3𝜋2 𝑛max

=𝑚𝜈 𝑚𝜈𝑣escape

3

3𝜋2

Spiral galaxies mn > 20–40 eV Dwarf galaxies mn > 100–200 eV

Neutrino Free Streaming (Collisionless Phase Mixing)

Neutrinos Neutrinos

Over-density

• At T < 1 MeV neutrino scattering in early universe is ineffective • Stream freely until non-relativistic • Wash out density contrasts on small scales

• Neutrinos are “Hot Dark Matter” • Ruled out by structure formation

Sky Map of Galaxies (XMASS XSC)

http://spider.ipac.caltech.edu/staff/jarrett/2mass/XSC/jarrett_allsky.html


Structure Formation with Hot Dark Matter

Neutrinos with Smn = 6.9 eV Standard LCDM Model

Structure fromation simulated with Gadget code Cube size 256 Mpc at zero redshift

Troels Haugbølle, http://users-phys.au.dk/haugboel


Neutrino Mass Limits Post Planck (2013)

Ade et al. (Planck Collaboration), arXiv:1303.5076

CMB alone constraining Smn CMB + BAO constraining Smn + Neff

CMB + BAO limit: Smn < 0.23 eV (95% CL)


Future Cosmological Neutrino Mass Sensitivity

Basse, Bjælde, Hamann, Hannestad & Wong, arXiv:1304.2321: Dark energy and neutrino constraints from a future EUCLID-like survey

ESA’s Euclid satellite to be launched in 2020 Precision measurement of the universe out to redshift of 2

Pin down the neutrino mass in the sky!


Neutrinos as Astrophysical Messengers

Nuclear Reactors

Particle Accelerators

Earth Atmosphere (Cosmic Rays)

Earth Crust (Natural Radioactivity)

Sun

Supernovae (Stellar Collapse) SN 1987A

Cosmic Big Bang (Today 330 n/cm3) Indirect Evidence

Astrophysical Accelerators


Geo Neutrinos: What is it all about?

We know surprisingly little about the Earth’s interior

• Deepest drill hole ~ 12 km

• Samples of crust for chemical analysis available (e.g. vulcanoes)

• Reconstructed density profile from seismic measurements

• Heat flux from measured temperature gradient 30-44 TW (Expectation from canonical BSE model ~ 19 TW from crust and mantle, nothing from core)

• Neutrinos escape unscathed

• Carry information about chemical composition, radioactive energy production or even a hypothetical reactor in the Earth’s core


Geo Neutrinos Expected Geoneutrino Flux

Reactor Background

KamLAND Scintillator-Detector (1000 t)


Reactor On-Off KamLAND Data

KamLAND Collaboration, arXiv:1303.4667 (2013)

Scintillator Purification

KamLAND-Zen Construction

2011 Earthquake Reactors shut down


KamLAND Geo-Neutrino Flux

KamLAND Collaboration, arXiv:1303.4667 (2013)

116−27+28 Geoneutrino events

(U/Th = 3.9 fixed) Separately free fitting: U 116 events Th 8 events

Beginning of neutrino geophysics!


Applied Anti-Neutrino Physics (AAP)

Applied Anti-Neutrino Physics (AAP) Annual Conference Series since 2004 • Neutrino geophysics • Reactor monitoring (“Neutrinos for Peace”)

• Relatively small detectors can measure nuclear activity without intrusion

• Of interest for monitoring by International Atomic Energy Agency (Monitors fissile material in civil nuclear cycles)


Cosmic Rays

Air Shower: 1019 eV primary particle 100 billion secondary particles at sea level


Cosmic Rays

Air Shower: 1019 eV primary particle 100 billion secondary particles at sea level Victor Hess (1911/12)


Cosmic Rays

Air Shower: 1019 eV primary particle 100 billion secondary particles at sea level Victor Hess (1911/12)

100 years later we are still asking

What are the sources for the primary

cosmic rays?


Neutrino Beams: Heaven and Earth

Target: Protons or Photons

Approx. equal fluxes of photons & neutrinos

Equal neutrino fluxes in all flavors due to oscillations

F. Halzen (2002)

𝜋0

𝜸

𝜋±

𝝁 𝝂𝝁

𝒆 𝝂𝒆𝝂𝝁

𝝂𝒆𝝂𝝁𝝂𝝉

p


Nucleus of the Active Galaxy NGC 4261


Nucleus of the Active Galaxy NGC 4261


IceCube Neutrino Telescope at the South Pole Instrumentation of 1 km3 antarctic ice with ~ 5000 photo multipliers completed December 2010


Two High-Energy Events in IceCube

Ernie ~ 1.1 PeV Bert ~ 1.3 PeV


Ernie & Bert and 26 Additional Events in IceCube

Significance of all 28 events: 4.1s, Background 10.6−3.6+5.0

Ernie & Bert


SN 1006 over Sydney

Supernova Neutrinos


SN 1006 over Sydney

Supernova Neutrinos


Crab Nebula


Stellar Collapse and Supernova Explosion

Hydrogen Burning

Main-sequence star Helium-burning star

Helium Burning

Hydrogen Burning



Hydrogen Burning

Main-sequence star Helium-burning star

Helium Burning

Hydrogen Burning

Onion structure

Degenerate iron core: r 109 g cm-3

T 1010 K MFe 1.5 Msun RFe 3000 km

Collapse (implosion)



Collapse (implosion)



Collapse (implosion) Explosion Newborn Neutron Star

~ 50 km

Proto-Neutron Star

r ~ rnuc = 3 1014 g cm-3

T ~ 30 MeV



Newborn Neutron Star

~ 50 km

Proto-Neutron Star

r ~ rnuc = 3 1014 g cm-3

T ~ 30 MeV

Neutrino

cooling by

diffusion

Gravitational binding energy

Eb 3 1053 erg 17% MSUN c2

This shows up as 99% Neutrinos 1% Kinetic energy of explosion 0.01% Photons, outshine host galaxy

Neutrino luminosity

Ln ~ 3 1053 erg / 3 sec ~ 3 1019 LSUN

While it lasts, outshines the entire visible universe


Diffuse Supernova Neutrino Background (DSNB)

• Approx. 10 core collapses/sec in the visible universe

• Emitted 𝜈 energy density ~ extra galactic background light ~ 10% of CMB density

• Detectable 𝜈𝑒 flux at Earth ∼ 10 cm−2 s−1 mostly from redshift 𝑧 ∼ 1

• Confirm star-formation rate

• Nu emission from average core collapse & black-hole formation

• Pushing frontiers of neutrino astronomy to cosmic distances!

Beacom & Vagins, PRL 93:171101,2004

Window of opportunity between reactor 𝜈𝑒 and atmospheric 𝜈 bkg


Sanduleak -69 202 Sanduleak -69 202

Large Magellanic Cloud Distance 50 kpc (160.000 light years)

Tarantula Nebula


Sanduleak -69 202 Sanduleak -69 202

Large Magellanic Cloud Distance 50 kpc (160.000 light years)

Tarantula Nebula

Supernova 1987A 23 February 1987


Neutrino Signal of Supernova 1987A

Kamiokande-II (Japan) Water Cherenkov detector 2140 tons Clock uncertainty 1 min

Irvine-Michigan-Brookhaven (US) Water Cherenkov detector 6800 tons Clock uncertainty 50 ms

Baksan Scintillator Telescope (Soviet Union), 200 tons Random event cluster ~ 0.7/day Clock uncertainty +2/-54 s

Within clock uncertainties, all signals are contemporaneous


Do Neutrinos Gravitate?

Early light curve of SN 1987A

• Neutrinos arrived several hours before photons as expected • Transit time for 𝜈 and 𝛾 same (160.000 yr) within a few hours

Shapiro time delay for particles moving in a gravitational potential

Δ𝑡 = −2 𝑑𝑡𝐵

𝐴Φ 𝑟 𝑡

For trip from LMC to us, depending on galactic model,

Δ𝑡 ≈ 1–5 months

Neutrinos and photons respond to gravity the same to within

1–4 × 10−3

Longo, PRL 60:173, 1988 Krauss & Tremaine, PRL 60:176, 1988


Supernova 1987A Energy-Loss Argument

SN 1987A neutrino signal

Late-time signal most sensitive observable

Emission of very weakly interacting particles would “steal” energy from the neutrino burst and shorten it. (Early neutrino burst powered by accretion, not sensitive to volume energy loss.)

Neutrino diffusion

Neutrino sphere

Volume emission of new particles


Flavor Oscillations in Core-Collapse Supernovae

Neutrino sphere

MSW region

Neutrino flux

Flavor eigenstates are propagation eigenstates

Neutrino-neutrino refraction causes a flavor instability, flavor exchange between different parts of spectrum


Neutrino Oscillations in Matter

Lincoln Wolfenstein

Neutrinos in a medium suffer flavor-dependent refraction

f

Z n n n n

W

f

Typical density of Earth: 5 g/cm3

𝑉weak = 2𝐺F × 𝑁e − 𝑁n 2

−𝑁n 2 for 𝜈efor 𝜈μ

Δ𝑉weak ≈ 2 × 10−13 eV = 0.2 peV


Flavor-Off-Diagonal Refractive Index

2-flavor neutrino evolution as an effective 2-level problem

i𝜕

𝜕𝑡

𝜈𝑒𝜈𝜇= 𝐻𝜈𝑒𝜈𝜇

𝐻 =𝑀2

2𝐸+ 2𝐺F

𝑁𝑒 −𝑁𝑛20

0 −𝑁𝑛2

+ 2𝐺F𝑁𝜈𝑒 𝑁⟨𝜈𝑒 𝜈𝜇𝑁⟨𝜈𝜇 𝜈𝑒 𝑁𝜈𝜇

Effective mixing Hamiltonian

Mass term in flavor basis: causes vacuum oscillations

Wolfenstein’s weak potential, causes MSW “resonant” conversion together with vacuum term

Flavor-off-diagonal potential, caused by flavor oscillations.

(J.Pantaleone, PLB 287:128,1992)

Flavor oscillations feed back on the Hamiltonian: Nonlinear effects!

𝝂

Z n n


Collective Supernova Nu Oscillations since 2006 Two seminal papers in 2006 triggered a torrent of activities Duan, Fuller, Qian, astro-ph/0511275, Duan et al. astro-ph/0606616 Balantekin, Gava & Volpe [0710.3112]. Balantekin & Pehlivan [astro-ph/0607527]. Blennow, Mirizzi & Serpico

[0810.2297]. Cherry, Fuller, Carlson, Duan & Qian [1006.2175, 1108.4064]. Cherry, Wu, Fuller, Carlson, Duan & Qian

[1109.5195]. Cherry, Carlson, Friedland, Fuller & Vlasenko [1203.1607]. Chakraborty, Choubey, Dasgupta & Kar

[0805.3131]. Chakraborty, Fischer, Mirizzi, Saviano, Tomàs [1104.4031, 1105.1130]. Choubey, Dasgupta, Dighe &

Mirizzi [1008.0308]. Dasgupta & Dighe [0712.3798]. Dasgupta, Dighe & Mirizzi [0802.1481]. Dasgupta, Dighe, Raffelt

& Smirnov [0904.3542]. Dasgupta, Dighe, Mirizzi & Raffelt [0801.1660, 0805.3300]. Dasgupta, Mirizzi, Tamborra &

Tomàs [1002.2943]. Dasgupta, Raffelt & Tamborra [1001.5396]. Dasgupta, O'Connor & Ott [1106.1167]. Duan

[1309.7377]. Duan, Fuller, Carlson & Qian [astro-ph/0608050, 0703776, 0707.0290, 0710.1271]. Duan, Fuller & Qian

[0706.4293, 0801.1363, 0808.2046, 1001.2799]. Duan, Fuller & Carlson [0803.3650]. Duan & Kneller [0904.0974].

Duan & Friedland [1006.2359]. Duan, Friedland, McLaughlin & Surman [1012.0532]. Esteban-Pretel, Mirizzi, Pastor,

Tomàs, Raffelt, Serpico & Sigl [0807.0659]. Esteban-Pretel, Pastor, Tomàs, Raffelt & Sigl [0706.2498, 0712.1137].

Fogli, Lisi, Marrone & Mirizzi [0707.1998]. Fogli, Lisi, Marrone & Tamborra [0812.3031]. Friedland [1001.0996]. Gava

& Jean-Louis [0907.3947]. Gava & Volpe [0807.3418]. Galais, Kneller & Volpe [1102.1471]. Galais & Volpe

[1103.5302]. Gava, Kneller, Volpe & McLaughlin [0902.0317]. Hannestad, Raffelt, Sigl & Wong [astro-ph/0608695].

Wei Liao [0904.0075, 0904.2855]. Lunardini, Müller & Janka [0712.3000]. Mirizzi [1308.5255, 1308.1402]. Mirizzi,

Pozzorini, Raffelt & Serpico [0907.3674]. Mirizzi & Serpico [1111.4483]. Mirizzi & Tomàs [1012.1339]. Pehlivan,

Balantekin, Kajino & Yoshida [1105.1182]. Pejcha, Dasgupta & Thompson [1106.5718]. Raffelt [0810.1407,

1103.2891]. Raffelt, Sarikas & Seixas [1305.7140]. Raffelt & Seixas [1307.7625]. Raffelt & Sigl [hep-ph/0701182].

Raffelt & Smirnov [0705.1830, 0709.4641]. Raffelt & Tamborra [1006.0002]. Sawyer [hep-ph/0408265, 0503013,

0803.4319, 1011.4585]. Sarikas, Raffelt, Hüdepohl & Janka [1109.3601]. Sarikas, Tamborra, Raffelt, Hüdepohl &

Janka [1204.0971]. Saviano, Chakraborty, Fischer, Mirizzi [1203.1484]. Väänänen & Volpe [1306.6372]. Volpe,

Väänänen & Espinoza [1302.2374]. Vlasenko, Fuller Cirigliano [1309.2628]. Wu & Qian [1105.2068].


Operational Detectors for Supernova Neutrinos

Super-K (104) KamLAND (400)

MiniBooNE (200)

In brackets events for a “fiducial SN” at distance 10 kpc

LVD (400) Borexino (100)

IceCube (106)

Baksan (100)

HALO (tens)

Daya Bay (100)


SuperNova Early Warning System (SNEWS)

http://snews.bnl.gov

Early light curve of SN 1987A

Coincidence Server @ BNL

Super-K

Alert

Borexino

LVD

IceCube • Neutrinos arrive several hours before photons • Can alert astronomers several hours in advance


Local Group of Galaxies

Current best neutrino detectors sensitive out to few 100 kpc

With megatonne class (30 x SK) 60 events from Andromeda


The Red Supergiant Betelgeuse (Alpha Orionis) First resolved image of a star other than Sun

Distance (Hipparcos) 130 pc (425 lyr)

If Betelgeuse goes Supernova: • 6 107 neutrino events in Super-Kamiokande • 2.4 103 neutrons /day from Si burning phase (few days warning!), need neutron tagging [Odrzywolek, Misiaszek & Kutschera, astro-ph/0311012]


IceCube as a Supernova Neutrino Detector

Pryor, Roos & Webster, ApJ 329:355, 1988. Halzen, Jacobsen & Zas, astro-ph/9512080. Demirörs, Ribordy & Salathe, arXiv:1106.1937.

• Each optical module (OM) picks up Cherenkov light from its neighborhood

• ~ 300 Cherenkov photons per OM from SN at 10 kpc, bkgd rate in one OM < 300 Hz

• SN appears as “correlated noise” in ~ 5000 OMs

• Significant energy information from time-correlated hits

SN signal at 10 kpc 10.8 Msun simulation of Basel group [arXiv:0908.1871]

Accretion

Cooling


First Realistic 3D Simulation (27 M⊙ Garching Group)


Variability seen in Neutrinos (3D Model)

Tamborra, Hanke, Müller, Janka & Raffelt, arXiv:1307.7936 See also Lund, Marek, Lunardini, Janka & Raffelt, arXiv:1006.1889


Next Generation Large-Scale Detector Concepts

Memphys

Hyper-K

DUSEL LBNE

Megaton-scale water Cherenkov

5-100 kton liquid Argon

100 kton scale scintillator

LENA HanoHano


LENA: From Dream to Reality

50 kt Scintillator


LENA: From Dream to Reality

50 kt Scintillator

Juno (formerly Daya Bay II), Collaboration formed (2014) 20 kt scintillator detector Hierarchy determination with reactor neutrinos Also good for low-energy neutrino astronomy


Summary

Understanding neutrino internal properties — a mature field • Neutrino mixing parameters: Matrix well known from astro and lab evidence • New experiments for missing parameters in the making • Absolute masses yet to be determined (KATRIN, cosmology) • Majorana nature yet to be found (neutrino-less double beta expts) Neutrinos as astrophysical messengers — a field in its infancy • Detailed measurement of solar nus (ca 60,000 events in Super-K) • First geo-neutrinos (ca 116 events in KamLAND) • SN 1987A (ca 20 events) • First high-E events in IceCube (Ernie, Bert, and 26 others)

- More statistics needed in all of these areas: bigger/better detectors planned or discussed - Waiting for next nearby supernova

Neutrinos at the center

Neutrinos: Ghostparticles of the UniverseGeorg Raffelt, MPI Physics, Munich Physics Colloquium, UNSW, Sydney, 4 March 2014 Neutrinos –Neutrinos Ghost Particles of the Universe Ghost

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