Neutrino Physics
description
Transcript of Neutrino Physics
Neutrino PhysicsNeutrino Physics
L. Oberauer, TU München
Graduiertenkolleg
Bad Honnef, August 2006
ContentContent
Neutrino sourcesNeutrino sources
Intrinsic propertiesIntrinsic properties
oscillationsoscillations
masses and mixing parametermasses and mixing parameter
Neutrinos as probesNeutrinos as probes
from the Earthfrom the Earth
from astrophysical sourcesfrom astrophysical sources
Charge 0 -1 +
2/3 -1/3
Why are neutrinos intresting ?
Neutrinos undergo only weak interactions
•Neutrinos are neutral – intrinsic properties
•Neutrinos as probes – astrophysical applications
Interactions w w
,e w,e,s
Natural Neutrino Sources
(experimentally verified)
Sun
(since 1970)
Earth (since 2005)
Supernovae (1987)
Atmosphere (since ~1990)
Natural Neutrino Sources
(not yet verified)
Big Bang
Active galactic nuclei
Supernovae remnants ?,
Gamma ray bursts ?,
Supernovae relic neutrinos ?...
Energy Spectra of Astrophysical neutrinos
thermal sources
Non-thermal sources
Neutrinos (homemade)
Nuclear Reactors
(beta decays of fission products: e)
Accelerators
pion production and subsequent decay in flight:
Intrinsic Neutrino Properties
• Neutrino masses ?
• Neutrino mixing ?
• Dirac or Majorana particle ?
• CP violation ?
• Neutrino magnetic moment ?
Neutrino oscillations observed,
Missing mixing angle 13
Absolute masses and hierarchy ?
2
1
cossin
sincos
e
21
22
221 mmm
E
Lm
P ee
2sin)2(sin1
)(22122
Survival probability:
0 1 2 3L in Losz
Neutrino Oscillations
L ≈ 20 km
L ≈ 13000 km
atmosphericneutrinos:Ev ~ GeV
E
LmP atm
atmx
222 27.1
sin2sin)(
Oscillations and Atmospheric Neutrinos
Pion production and subsequent decays (incl. muon)
Atmospheric Neutrinos and SuperKamiokande
Charged current reactions
+ N + N` and
e + N e + N`
50 kt Water Cherenkov Detector
νμ
νe
Electron events Muon events
Up going Up going Neutrinos
e
No-oscillation
Oscillation
Result atmospheric Neutrino-Oscillations
Best fit:m2
atm = 2.5×10-3
eV2
sin22θatm = 1.0
Best fit:m2
atm = 2.5×10-3
eV2
sin22θatm = 1.0
Confirmed by
•MACRO (Gran Sasso)
•Soudan (USA)
•K2K accelerator long baseline (250 km) experiment
•MINOS (USA) acc. exp. in 2006
Oscillations and Solar Neutrinos
Neutrino Energy in MeV
MeV7.2622He4 4 eep
The Solar Neutrino Problem
Solar Model
0,5
Sudbury Neutrino Observatory Sudbury Neutrino Observatory SNOSNO
charged current interaction (cc)
e + D p + p + e neutral current interaction (nc)
x + D x + p + n
elastic Neutrino-Electron scattering (cc
+ nc)
x + e x + e
1kt Cherenkov Detector with heavy water
SNO ResultSNO Result
Flavour transition Flavour transition discovered: 7 sigma !discovered: 7 sigma !Reasonable Reasonable agreement with solar agreement with solar modelmodel
Neutrinos from the Sun (e) transform into or
Solar Neutrino OscillationSolar Neutrino Oscillation
Determination of Determination of
1212 ~ 34 ~ 3400
e e
mm22 ~ 8 x 10 ~ 8 x 10-5-5 eV eV22
Confirmation by reactor Confirmation by reactor experiment experiment KamLANDKamLAND
The solar matter effect – evidence by The solar matter effect – evidence by GALLEX/GNOGALLEX/GNO
GALLEX/GNO
SNO
• Evidence for matter effect inside the Sun
• m2 > m1
• Why are neutrino masses so small?
• GUT
• Leptogenesis
Survival probability electron neutrino
pp- 7Be
8B
Phys. Rev. Lett. 90 (2003) 021802
Evidence for Oscillation
ILL 1979ILL 1979
Gösgen (1986)Chooz (1998)
nepe Reactor Experiments
Bugey (1994)
KamLAND: Energy spectrumKamLAND: Energy spectrum
3
2
1
1212
1212
1313
1313
2323
2323
100
0
0
0
010
0
0
0
001
cs
sc
ces
esc
cs
sci
ie
θsol
θ13, δθatm
Parametrization Neutrino mixing
Flavor Eigenstates Mass Eigenstates
2 mixing angles are measured:
CP violating phase New experiments
1313 from reactors? from reactors?
P(P(eeee) = 1 ) = 1
– – coscos441313 sin sin22 2 21212 sin sin22((mm22solsol L/4E) – L/4E) –
sinsin22 2 21313 sin2 ( sin2 (mm22atmatm L/4E) L/4E)
no CP termsno CP terms
no matter effectsno matter effects
P
L/E(km/MeV)
solar
atmospheric
Letter of Intent: Double-Letter of Intent: Double-ChoozChooz
• d~1.05 km
• P~8.4 GW
• 300mwe far detector
• no excavation for far detector
Far Detector (~300mwe shielding)
Near Detector for reactor monitoring
Double-CHOOZDouble-CHOOZ(far) Detector(far) Detector
Puit existant
Gamma catcher: scintillator with no Gd
7 m
7 m
BUFFER Mineral Oil
7 m
Shielding steel and external vessel
Target- Gd loaded scintillator: ~ 85 /d (far) and ~ 4 103/d (near)
photomultipliers
Inner veto
Sensitivity of Double ChoozSensitivity of Double Chooz
Exclusion limit 90% cl for
dm2 = 2.8 10-3 eV2
and a final systematic uncertainty of 0.6%
732 km
LNGS
Neutrino beam from CERN to Gran Neutrino beam from CERN to Gran SassoSasso
Precision Tracker (PT)Universität Hamburg:
Precision Tracker (PT)Universität Hamburg:
DetectorDetector
8.3kg
Aktives Target:200.000 Blei-Emulsions-Ziegel= ca. 1.800 Tonnen
Universität Münster
full mixing, 5 years run @ 4.5 x1019 pot / year
signalsignal
((mm22 = = 1.1.99 x 10 x 10-3-3 eV eV22))
signalsignal
((mm22 = = 2.2.44 x 10 x 10-3-3 eV eV22))
signalsignal
((mm22 = = 3.0x 103.0x 10-3-3 eV eV22))
BKGDBKGD
OPERAOPERA1.8 kton fid.1.8 kton fid.
6.66.6(10)(10) 10.510.5(15.8)(15.8) 16.416.4(24.6)(24.6) 0.70.7(1.1)(1.1)
+ brick finding+ brick finding
+ 3 prong decay+ 3 prong decay8.08.0(12.1)(12.1) 12.812.8(19.2)(19.2) 19.919.9(29.9)(29.9) 1.01.0(1.5)(1.5)
Background Background reduction reduction 8.08.0(12.1)(12.1) 12.812.8(19.2)(19.2) 19.919.9(29.9)(29.9) 0.80.8(1.2)(1.2)
(…) with CNGS beam upgrade (X 1.5)
→→ sensitivitysensitivity
BOREXINO sees neutrinos from BOREXINO sees neutrinos from CERN (August 2006) !CERN (August 2006) !
Cosmic muons (background)
Time of flight (CERN to LNGS) ~ 2.4 ms
Data analysis of 30 h measurement and 55 t water as target
First neutrino events in BOREXINO
ΘΘ1313 with accelerator physics with accelerator physics
with
(anti-v)
Neutrino appearance:Neutrino appearance:
θ13 , δCP, Mass hierarchy but degeneracy & correlation effects!
Present limit from CHOOZ: sin2(213) < 0.2
Present limit from CHOOZ: sin2(213) < 0.2
Neutrino Superbeam ProjectsNeutrino Superbeam ProjectsJapan: Japan: – T2K – phase I: T2K – phase I:
0.75MW (JPARC)0.75MW (JPARC) + SuperK (22.5kt) (ab 2009) + SuperK (22.5kt) (ab 2009) sinsin22221313>0.006 (90%) (5 Jahre)>0.006 (90%) (5 Jahre)
– T2K – phase II: T2K – phase II: 4 MW + HyperK (500-1000 kt) (≥ 2015)4 MW + HyperK (500-1000 kt) (≥ 2015)
USA:USA:NOvA: Fermilab NuMI beam (0.4 MW) +NOvA: Fermilab NuMI beam (0.4 MW) +off-axis detector (surface!, 50kt) (ab 2009)off-axis detector (surface!, 50kt) (ab 2009)
Sensitivity of future experiments Sensitivity of future experiments onon θθ1313
90% CL90% CL
from Huber, Lindner, Rolinec, Schwetz, Winter hep-ph/0403068
← reactor
← super beam
Absolute Neutrino Mass Absolute Neutrino Mass MeasurementsMeasurements
Kinematic tests (tritium decay)Kinematic tests (tritium decay)
Search for the neutrinoless double-Search for the neutrinoless double-beta decaybeta decay
CL%95eV2.2eV1.22.22.1 22
mm
Mainz Data (1998,1999,2001)
Direct Mass Experiments: Tritium Direct Mass Experiments: Tritium ββ-Decay-Decay
e -33 eHe H e -33 eHe H
222i
iei mUm
E0 = 18.6 keV
KATRIN
~70 m beamline, 40 s.c. solenoids
The KArlsruhe TRItium Neutrino Experiment
The KArlsruhe TRItium Neutrino Experiment
Commissioning in 2008
mv < 0.2eV (90%CL)
Neutrinoless Double-Beta-Neutrinoless Double-Beta-DecayDecay
0: (A,Z) (A,Z+2) + 2e-
d
d
u
u
e-
e-
W-
W- e
e
L=2
Majorana nature, Mass scale, Majorana CP phases
mee = |i Uei ² mi |Effective neutrino mass:
21 233
222
211
ie
ieeee eUmeUmUmm
CL) (90% eV 35.0ee
mHeidelberg-Moskau Collaboration, Eur.Phys.J. A12 (2001) 147
IGEX Collaboration, hep-ex/0202026, Phys. Rev. C59 (1999) 2108
H.V. Klapdor-Kleingrothaus, A. Dietz, O. Chkvorets, I.V. Krivosheina, NIM A, 2004
Peak at 2039 keV in the Heidelberg-Moscow experiment !
Effect or background ??
Evidence for neutrinoless Double-beta Decay ?
Wanted: New experiments !
• GERDA ( 76Ge)
• Cuoricino (130Te in cryogenic detectors)
• NEMO (different isotopes in large drift-chambers)
• COBRA (116Cd)
• SNO+ (150Nd)
…and many more projects
Phase I: 20kg enriched (86%) 76Ge, vgl. HDMPhase II: 35-40kgPhase III: ~500kg
GERGERmanium manium DDetector etector AArrayrrayMethod:
HP Ge-diodes (enriched in 76Ge) in cryogenic fluid shield(optional active) .
Qββ = 2039 keV
HP Ge-diodes (enriched in 76Ge) in cryogenic fluid shield(optional active) .
Qββ = 2039 keV
GERDA Sensitivity & Neutrino GERDA Sensitivity & Neutrino MassMass
| m
ee|
in e
V
Lightest neutrino (m1) in eV
F.F
eruglio, A. S
trumia, F
. Vissani, N
PB
659
H.V. Klapdor-Kleingrothaus, A. Dietz, O. Chkvorets, I.V. Krivosheina, NIM A, 2004Phase I:
Phase II:
Phase III:
Neutrinos as ProbesNeutrinos as Probes
……from the Earth and from from the Earth and from Astrophysical ObjectsAstrophysical Objects
Geo-NeutrinosGeo-Neutrinos
Direct neutrino observation:• what is the contribution of radioactivity to the Earth‘s heat flow (~ 40 TW) ?
• direct test of the Bulk Silicate Earth model
• what is the energy source of the Earth magnetic field ?
• test of unorthodox models (i.e. breeder reactor in the core)
First detection in KamLAND
Nature, 28. July 2005
Geo-neutrino energy spectrum
reactors
reactors
background
Excess due to Geo-neutrinos
Future Neutrino ObservatoriesFuture Neutrino ObservatoriesUnsegmented 50 kt liquid scintillator
LENAHyperKamiokande (1 Mt Water Cherenkov)
…Liquid Argon ~100 kt TPC
LAGUNALAGUNA
Large Aparatus for Grand Unification and Large Aparatus for Grand Unification and Neutrino AstronomyNeutrino Astronomy
European initiative (France, Germany, European initiative (France, Germany, Italy, Switzerland, UK, Poland, Finland)Italy, Switzerland, UK, Poland, Finland)
Aim: Design studies for all 3 kinds of Aim: Design studies for all 3 kinds of detevtors (water Ch, scintillator, liquid detevtors (water Ch, scintillator, liquid argon) until ~ 2010 argon) until ~ 2010
Physics goals of future Neutrino Physics goals of future Neutrino ObservatoriesObservatories
Gravitational collapseGravitational collapseStar formation rate in the early universeStar formation rate in the early universeThermonuclear fusion reactionsThermonuclear fusion reactionsBaryon number violation (Proton decay)Baryon number violation (Proton decay)Leptonic CP – violationLeptonic CP – violationGeophysicsGeophysicsIndirect search for Dark MatterIndirect search for Dark MatterActive Galactic Nuclei – UHE NeutrinosActive Galactic Nuclei – UHE Neutrinos
One example for LENA: Detection of the One example for LENA: Detection of the Diffuse Supernova Neutrino Background Diffuse Supernova Neutrino Background
(DSNB) ?(DSNB) ?
• up to now only limits
• flux and spectral shape depend on
Star formation rate
Gravitational collapse model
Star formation rate
Star formation: Large uncertainties
Optical and infrared observations
LENA: 70 until 120 events in 10 years
1 < z < 2: around 25%
Pulse shape analysis: distinction between models of supernova mechanism
Extremely Large ObservatoriesExtremely Large Observatories
Km3 Cherenkov detector in the mediterranian sea
Km3 Cherenkov detector at the South Pole (Ice Cube)
Amanda
Frejus
Eν E-3.8
A change in the slope would indicate a non-atmospheric component
Atmospheric neutrino Waxmann-Bahcall limit: Model-independent upper bound
= 2 = 00-03 combined
Diffusive sources
Limits from Amanda
Ice-Cube ~ 3 10-9
ConclusionsConclusions
• New results recently
• Neutrino masses and mixing established
• Physics beyond the standard model
• New window to astrophysical observations