Other Physics with Geo-Neutrino Detectors

Transcription

1 Other Physics with Geo-Neutrino Detectors M. Lindner Technical University Munich Neutrino Geophysics Workshop Hawaii, Dec , 2005

2 Neutrinos & New Physics neutrinos as probes neutrino properties & particle physics + Manfred Lindner Neutrino Geophysics 2

3 Motivation: Physics Beyond the SM gauge bosons Higgs quarks leptons gauge hierarchy problem δm H2 ~ Λ 2 3 generations, fermion rep. many parameters (m i,mixings) unification into GUTs m ν =(md ) T M R -1 m D SUSY ~TeV ~Λ GUT +seesaw experimental facts: Dark Matter Dark Energy neutrino masses baryon asymetry:m ν > 0 astrophysics & cosmology Manfred Lindner Neutrino Geophysics 3

4 Topics Geo-neutrinos large & expensive detectors other motivations Proton decay (baryon number violation) Supernova neutrinos (GR collapse of old stars) Supernova relic neutrinos (star early U) Solar neutrinos (CNO, pep, 7 Be stellar evolution) Nuclear monitoring Neutrino oscillations ( precision flavour physics) - solar - atmospheric - reactor neutrinos - neutrino beams Manfred Lindner Neutrino Geophysics 4

5 Large LENA like Detektors based on LiSci 100m 30m Muon veto ~12000 Pms (50cm) A possible location: Pyhäsalmi mine, Finnland ~ 1450 m depth low radioactivity access via trucks Manfred Lindner Neutrino Geophysics 5

6 Liquid Scintillator Technology Modern scintillators: e.g. PXE, or PXE/mineral oil mixture - non hazardous, flashpoint 145 C easy handling: transport by railway, loading by pipeline moderate security problem - density high light yield low energy events - low U,Th background level see weak sources - experience with BOREXINO Gran Sasso 372 pe / 20% coverage attenuation length ~ nm after purification: ~ 12 m (R&D for LENS) ~ 120 pe/mev in LENA low energy threshold (sub-mev) good resolution in energy and position reconstruction Manfred Lindner Neutrino Geophysics 6

7 SUSY GUT scale: Proton Decay and GUTs Preferred decay modes: τ = (0.3 3) y S. Raby et al, 2002 τ < y Babu, Pati, Wilzcek, 1998 τ ~ (M GUT ) 5 LENA sensitivity Manfred Lindner Neutrino Geophysics 7

8 Proton LENA favoured decay mode in some SUSY theories: p K ν K is invisible in Water Cherenkov detectors K and K-decay visible in LENA Time information high efficiency 12.8ns µ decay: ~2.2µs >µ ν event structure: - 3-fold coincidence - energy spectrum strong bg. rejection K T. Marrodan Diploma Thesis 2005 T.M. et al. hep-ph/ Manfred Lindner Neutrino Geophysics 8

9 Typical background: Atmospheric neutrino event ν + Ν > Ν + µ Potential of LENA for p Kν no signal seen (90%cl) τ > 4 x y Super Kamiokande limit τ > 2.3 x y 41 events in LENA (0.5 bg evts.) Manfred Lindner Neutrino Geophysics 9

10 SN IIa: Collaps of a typical star ~10 57 ν s ~99% of the energy in ν s ν s essential for explosion 3d simulations do not explode (so far... 2d 3d, convection?... ) Supernova Neutrinos Dighe, Smirnov MSW: SN & Earth Very sensitive to - finite θ 13 -sgn( m 2 ) Manfred Lindner Neutrino Geophysics 10

11 2 possibilities: Supernova neutron star or black hole Keeps cooling... abrupt end of ν emission impressive signal of a black hole in neutrino light neutrino masses edge of ν-signal Manfred Lindner Neutrino Geophysics 11

12 Supernovae & Gravitational Waves gravitational wave emission quadrupol moment of the explosion Dimmelmeier, Font, Müller additional information about galactic SN global fits: optical + neutrinos + gravitational waves neutrino properties + SN explosion dynamics SN1987A: strongest constraints on large extra dimensions Manfred Lindner Neutrino Geophysics 12

13 Supernova Signal at SK Accretion Phase Kelvin-Helmholtz Cooling Phase Simulation for Super-Kamiokande SN signal at 10 kpc Totani, Sato, Dalhed & Wilson Manfred Lindner Neutrino Geophysics 13

14 Amanda/IceCube as a Supernova Detector 8.5 kpc Signal in Amanda 8.5 kpc Signal in IceCube Each optical module (OM) picks up Cherenkov light from its neighborhood SN correlated noise between OMs Manfred Lindner Neutrino Geophysics 14

15 Galactic Supernovae with LENA Event rates for a typical type IIa SN at GC (~10 kpc) (1) (2) (3) (4) (5) (6) ν ν e e ν + ν ν ν e x x x + + p C + e C C e e e + p ν + + ν ν x x x + n B + e + p N C * (Q = 1.8 (Q = 13.4 (Q = 17.3 MeV) with 12 MeV) C MeV) 12 (elastic scattering (elastic scattering * C + γ _ ν e spectroscopy ν e spectroscopy ~ 65 off off (Q = E γ electrons) protons). = 15.1 NC sensitive to all flavours ~ 4000 and ~ 2200 ~7800 MeV) ~ 480 detect all flavour, neutrinos and anti-neutrinos Manfred Lindner Neutrino Geophysics 15

16 SN and Earth Matter Effects ν e scintillator = good resolution Water Cherenkov SN model independent modulations in the spectrum due to Earth matter effects θ 13, sign( m 2 ) Sighe, Smirnov Dighe, Keil, Raffelt Manfred Lindner Neutrino Geophysics 16

17 Supernova Relic Neutrinos reactor 8 B solar ν e hep solar ν e no LENA SK limit close to expectations LENA: ~9MeV threshold SRN: ~6 events / y 60 / 10 years atmospheric neutrinos SNR neutrinos information about star formation early universe Manfred Lindner Neutrino Geophysics 17

18 Reactor Neutrinos identical detectors many errors cancel E=4MeV 2km 4km 40km 80km Double Chooz KASKA Braidwood Angra, no degeneracies no correlations no matter effects Manfred Lindner Neutrino Geophysics 18

19 Neuclear Geo-neutrino Detectors reactors anti-neutrinos are an unwanted background huge rate high statistics reactor experiments for some time during existence of the detector a rescaling exercise: Double Chooz: 10t x 5GW x 5y = 0.25 GW kt y LENA=50kt x 200MW x 2.5y = 25 GW kt y different possibilities: - movable detectors - location where a power reactor turns on/off - mobile reactors J. Kopp, ML, A. Merle, M. Rolinec, to appear Manfred Lindner Neutrino Geophysics 19

20 Manfred Lindner Neutrino Geophysics 20

21 Sensitivity to sin 2 2θ GW kt y Double Chooz Manfred Lindner Neutrino Geophysics 21

22 Improvement by Combining two Baselines 5GW kt y, nuclear power ship scenario combine 0th + 1st osc. maximum (1+2 OK) Manfred Lindner Neutrino Geophysics 22

23 Solar Oscillation Parameters & Reactors Ideal baseline: 55 km ( KamLAND) additionally 40 and 70 km Events/year for 25 GW t y - main channel: reactor background nearest power Pyhaesalmi: Geo νs U: 923 -Geo νs Th: assume various geo-neutrino flux errors Manfred Lindner Neutrino Geophysics 23

24 m 2 sol for L=40km Manfred Lindner Neutrino Geophysics 24

25 m 2 sol for L=70km Manfred Lindner Neutrino Geophysics 25

26 sin 2 (2θ 12 ) for L=40km Manfred Lindner Neutrino Geophysics 26

27 sin 2 (2θ 12 ) for L=55km Manfred Lindner Neutrino Geophysics 27

28 sin 2 (2θ 12 ) for L=70km Manfred Lindner Neutrino Geophysics 28

29 R2D2 - Reactor Experiments Symmetric reactors,detectors: R1, R2, D1, D2 - may be different L 11 =L 22 and L 12 =L 21 Separate events from R 1 and R 2 R1 and R2 on/off times Neutron displacement Simplest case: 1d line-up R1 at detector D1: 1,5cm 6cm combined R2 High statistics: precise statistical separation N11, N21, N12, N22 self-calibration: N11/N21=N22/N12 Manfred Lindner Neutrino Geophysics 29 N11* N 22 = N 21* N12 r R 4 4 Huber, ML, Schwetz oscillation stable against size, backgrounds,... Improved sensitivity

30 Conclusions Geo-neutrinos: - interesting by itself - large & expensive detectors multiple purpose experiments Large LiSci detectors like LENA, HSD, EARTH, Super-Hanohano, address a broad physics program Different technologies - mega-ton water Cherenkov - large LiAr detectors - large LiSci physics / price: large LiSci very promising Manfred Lindner Neutrino Geophysics 30