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LAGUNA Large Apparatus for Grand Unification and Neutrino Astrophysics Launch meeting, Heidelberg, March 2007, Lothar Oberauer, TUM Why ? Neutrinos oscillations => New Particle Physics Main line besides future accelerator experiments Baryon number violation ? => Nucleon decay (Search for Proton Decay) Baryon asymmetry Leptogenesis ? Q13, CP violation in leptonic sector ? (Long Baseline Neutrino Experiments) Astrophysics New Neutrino Observatories wanted Neutrinos as probes Study of gravitational collapse (Supernova Neutrinos) Study of star formation in the early universe (Diffuse Supernovae Neutrinos Background) Precision study of thermonuclear fusion processes (Solar Neutrinos) Test of geophysical models (Geoneutrinos) LENA Low Energy Neutrino Astronomy Diffuse Supernovae Neutrino Background Supernova Neutrinos Solar Neutrinos Geoneutrinos Proton Decay LENA: Diffuse SN Background ne + p -> e+ + n ~25% of events are due to v’s originating from SN @ z>1! Rates depend on: supernova model, star formation rate, neutrino mass hierarchy Range 20 to 220 / 10 years “most probable” value ~ 100 M. Wurm et al., Phys. Rev D 75 (2007) 023007 Information on Supernova models & Star Formation rate (z~2) LENA: Diffuse SN Background optical measurements will determine the SNR with high accuracy with this input, the spectral slope of the DSN can be used to distinguish between different SN explosion scenarios comparison of count rates in the energy bins 10MeV < EB1 < 14MeV 15MeV < EB2 < 25MeV LENA: Supernova Neutrinos Assumption: Supernova II with 8 solar masses at 10 kpc distance ne flux and spectrum ne flux and spectrum LENA: Supernova Neutrinos Total neutrino flux Total energy spectrum LENA: Supernova Neutrinos n + p -> n + p Depending on threshold: p, nu scattering dominated by nm and nt Threshold ~ 50 pe (photoelectrons) LENA: Solar Neutrinos LENA Fiducial Volume for solar n: 18 x 103 m3 • High statistic ( ~ 5.4 x 103 / day ) 7Be n + e -> n + e test of small flux fluctuations in time • CNO and pep – neutrinos ( ~ 3 x 102 / day ) solar neutrino luminosity contribution of CNO cycle to solar energy release • Charged current ne (13C,13N) e- reaction ( ~ 103 / year ) spectroscopy of 8B-n at energies below 5 MeV (A. Ianni et al., hep-ph/0506171) LENA: Solar Neutrinos Standard MSW scenario Non standard Interactions ? (e.g. flavor changing neutral currents) 7Be pep CNO 8B Friedland, Lunardini, Peña-Garay, hep-ph/0402266 CNO and the age of Globular Clusters 14N(p,g)15O new value? (new result from LUNA) Prediction CNO-n altered by factor ~2 Age of Globular Clusters increased by factor 0.7 bis 1 Gy ! Measurement of CNO -n : determination of metallicity in the centre of the Sun LENA: Solar Neutrinos Electron recoil spectrum Requirements: low background levels in U, Th, 210Pb at least ~4000 m.w.e. shielding LENA: Geo Neutrinos • Detection via inverse beta decay • measurement of radiogenic contribution to terrestrial heat (~ 40 TW) • test of the Bulk Silicate Earth model • test of unorthodox models of Earth‘s core (is there a breeder reactor ?) Rate of Geo-neutrinos in LENA LENA @ Pyhäsalmi: ~ 1.5 x 103 events / year Scaling KamLAND result to LENA: Positron spectrum (arb. units) between 3 x 102 and 3 x 103 events / year Uranium Uranium + Thorium Proton Decay in Supersymmetry SU(5) GUT scale: Preferred decay modes: t = (0.3 – 3) 1034 y (S.Raby et al, 2002) t < 1035 y (Babu, Pati, Wilzcek, 1998) Proton Decay (non SUSY) (P. Nath 2006) Limits from SuperKamiokande: LENA: Proton Decay LENA: Proton Decay LENA: Separartion e- m-like events ? Conclusions • LAGUNA – Design study for a large future European observatory (Water, Argon, Scintillator) design study until ~ 2011 on APpec road map for Launch after design study completed • LENA – Physics Potential in Low Energy Neutrino Astronomy and Proton Decay Proton Decay: T. Marrodan-Undagoitia et al., Phys. Rev. D 72 (2005) 075014 Geo-Nus: K.. Hochmuth et al., Astropart. Phys. 27 (2007) 21 DSNB: M. Wurm et al., Phys. Rev. D 75 (2007) 023007