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LENA. LENA Delta. Low Energy Neutrino Astrophysics. Technische Universität München. ''... annus mirabilis''. A.Yu. Smirnov Venice 2004. December 4, 2002. K2K: ``Indication of neutrino oscillations in a 250 km …’’. December 6, 2002. ``First Results from KamLAND: Evidence for Reactor …’’.
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LENA LENA Delta Low Energy Neutrino Astrophysics Technische Universität München low energy neutrino astronomy
''... annus mirabilis'' A.Yu. Smirnov Venice 2004 December 4, 2002 K2K: ``Indication of neutrino oscillations in a 250 km …’’ December 6, 2002 ``First Results from KamLAND: Evidence for Reactor …’’ Ceremony of the Nobel Prize award: ``for pioneering contributions to astrophysics, in particular for the detection of cosmic neutrinos’’ December 10, 2002 Raymond Davis Jr. Masatoshi Koshiba February 11, 2003 WMAP: First year Wilkinson microwave anisotropy probe observations: determination of cosmological parameters September 3, 2003 ``Precise measurement of the solar neutrino Day/Night and seasonal variations in Super-Kamiokande-1’’ September 7, 2003 SNO salt phase results: ``Measurements of the Total…’’ Sloan Digital Sky Survey: ``Cosmological parameters…’’ October 27, 2003 low energy neutrino astronomy …? December ??, 2003 A Yu Smirnov
Solar Fusion Prozesses H. Bethe W. Fowler pp - 1 pp -2 pp -3 low energy neutrino astronomy
Situation nach GALLEX (~ 20 Jahre nach Homestake) Hinweis auf nicht standard Eigenschaften der Neutrinos Theoretische Vorhersagen low energy neutrino astronomy
Sonnen-n ändern ihren Flavour!(sie verwandeln sich auf dem Weg zur Erde vom e-Typ in den m, oder t-Typ) Insgesamt kommen genau so viele Neutrinos an wie vorausgesagt! low energy neutrino astronomy
BOREXINO • Real time low energy solar neutrinos • Long baseline reactor neutrinos • Terrestrial neutrinos • Supernova neutrinos • Search for magnetic moment • Double beta experiment (Cameo) low energy neutrino astronomy
Signal rate at full 7Be-n flux: 55/d /100t Signal rate in case of complete conversion in nm, nt : 9/d/100 t Signature of low energy Neutrinos in Borexino Electron recoil spectrum Signal for SSM ne - flux Signal for total flavour conversion Backgrund: U, Th < 10-16 and K < 10-14 low energy neutrino astronomy
Borexino in Hall C of Gran Sasso Liquid handling & scintillator purification Scintillator storage Borexino outer & inner detector Counting Test Facility DAQ electronics & clean room low energy neutrino astronomy
double innert vessel installed (nylon) low energy neutrino astronomy
Solar neutrino spectrum and experiments LENA - Rate 100* BOREXINO => 3000/day Homestake Kamiokande, SK SNO Gallex, Sage low energy neutrino astronomy
Fundamental results from brexino counting test facility 1/100 of Brexino Target mass • electron decay Back et al.,Phys Lett.B 525 (2002) 29-40 • nucleon decay into invisible. channels. Back et al.,Phys Lett.B 563 (2003) 23-34 • νmagnetic moment Back et al.,Phys Lett.B 563 (2003) 35-47 • Heavy νmixing Back et al.,JETP Lett. Vol.78 N.5 (2003) 261-266 • Pauli exclusion principle accepted in Eur.Phys.Journ. C (2004) Lena= 10000 * CTF low energy neutrino astronomy
LENA (Low Energy Neutrino Astrophysics) Idea: A large (~30 kt) liquid scintillator underground detector for Relic supernovae neutrino detection Search for Proton Decay Galactic supernova neutrino detection Neutrino properties Terrestrial neutrino detection Solar Neutrino Spectroscopy low energy neutrino astronomy
Npe ~ 100 / MeV beta P - decay event Scintillator: PXE , non hazard, flashpoint 145° C, density 0.99, ultrapure (as proven in Borexino design studies) low energy neutrino astronomy
Neutrino reactions in organic scintillator - - v(e) + e v(e) + e _ + v(e) + p n + e 12 12 v(x) + C C +γ v(e) + C N + e ec 12 12 - low energy neutrino astronomy
All n flavours; mono-energetic 15.1 MeV gamma line ne interaction; delayed coincidence with 11.0 msec low energy neutrino astronomy
Possible locations for LENA ? Underground mine ~ 1450 m depth, low radioactivity, low reactor n-background ! Access via trucks low energy neutrino astronomy
loading of detector via pipeline • transport of 30 kt PXE via railway • no fundamental security problem with PXE ! • no fundamental problem for excavation • standard technology (PM-encapsulation, electronics etc.) • LENA is feasible in Pyhäsalmi ! low energy neutrino astronomy
Pylos (Nestor Institute) in Greece, on the Cern Neutrino beam (off axis) low energy neutrino astronomy
Galactic Supernova neutrino detection with Lena Electron Antineutrino spectroscopy ~7800 Electron n spectroscopy ~ 65 Neutral current interactions; info on all flavours ~ 4000 and ~ 2200 ~ 480 low energy neutrino astronomy Event rates for a SN type IIa in the galactic center (10 kpc)
Visible proton recoil spectrum in a liquid scintillator all flavors nm, nt and anti-particles dominate low energy neutrino astronomy J. Beacom, astro-ph/0209136
Relative size of the different luminosities is not well known: it depends on uncertainties of the explosion mechanism and the equation of state of hot neutron star matter Supernova neutrino luminosity (rough sketch) T. Janka, MPA low energy neutrino astronomy
SNN-detection and neutrino oscillations Water Cherenkov Scintillator good resolution SNN-detection and neutrino oscillations Modulations in the energy spectrum due to matter effects in the Earth low energy neutrino astronomy Dighe, Keil, Raffelt (2003)
Preconditions for observation of those modulations • SN neutrino spectra ne and nm,t are different • distance L in Earth large enough • very good statistics • very good energy resolution low energy neutrino astronomy
LENA and relic Supernovae Neutrinos • SuperK limit very close to theoretical expectations • Threshold reduction from ~19 MeV (SuperK) to ~ 9 MeV with LENA • Method: delayed coincidence of ne p -> e n • Low reactor neutrino background ! • Information about early star formation period low energy neutrino astronomy
Reactor SK No background for LENA ! Reactor bg LENA ! LENA SNR rate: ~ 6 counts/y SRN Atmospheric neutrinos low energy neutrino astronomy
gianni fiorentini, ferrara univ. @ n2004 Heat flow Neutrino flow Geo-Neutrinos : a new probe of Earth’s interior • Determine the radiogenic contribution to terrestrial heat flow • Test a fundamental geochemical paradigm about Earh’s origin: the Bulk Sylicate Earth • Test un-orthodox / heretical models of Earth’s interior (K in the core, Herndon giant reactor) • A new era of applied neutrino physics ? low energy neutrino astronomy
The crust (and the upper mantle only) are directly accessible to geochemical analysis. U, K and Th are “lithofile”, so they accumulate in the (continental) crust. U In the crust is: Mc(U) » (0.3-0.4)1017Kg. The » 30 Km crust should contains roughly as much as the » 3000 km deep mantle. Concerning other elements: Th/U »4* and 40K/U »1 For the lower mantle essentially no direct information: one relies on data from meteorites through geo-(cosmo)-chemical (BSE) model… According to geochemistry, no U, Th and K should be present in the core. crust Where are U, Th and K? U. M. L. M. Core low energy neutrino astronomy
What to use … • Bulk Silicate Earth Model • Preliminary Reference Earth Model • Laboratory Experiments suggesting potassium-iron alloys in the core http://www.edu.pe.ca/southernkings/compositionch.htm low energy neutrino astronomy
Radioactive Elements low energy neutrino astronomy
First steps to get a neutrino picture of the earth Using the density profile given in the Preliminary Reference Earth Model to Divide Earth into shells of constant density with low energy neutrino astronomy
Angular resolution in LENA Momentum conservation (proton at rest) Max neutron scattering angle 2 MeV cosq = 0.95 3.2 MeV cosq = 0.79 low energy neutrino astronomy
LENA-Angular Resolution Sensitivity of LENA + resolution of CHOOZ (18°) Precision of neutron detection in cm Angular resolution of LENA: ~26° (half-cone aperture) low energy neutrino astronomy
Inhomogenous Earth 4 TW hot spot Standard model low energy neutrino astronomy
Summary-what can we do? • Test the U/Th of Bulk Silicate Earth • Test how much of the heat is primordial • Get the distribution of radioactive element throughout the earth • Test if there are radioactive elements (only potassium?) in the core • Test other things (nuclear reactor in core?) low energy neutrino astronomy
conclusions Angular resolution of LENA 26° Distinction between different geological models possible!! Chance for location of non-visible galactic SN low energy neutrino astronomy
KAMLAND: a first insight to terrestrial neutrinos • 6 Monate Daten ergibt einen Fit für N(Th+U) für E< 2.6 MeV • N(Th+U) = 9 ± 6* • Die Unsicherheit* ist dominiert durch Fluktuation der Reaktorsignale • Das Ergebnis ist mit jedem geophysikalischen Modell konsistent: Hrad=(0-100 TW). low energy neutrino astronomy
Proton Decay and LENA • p K n • This decay mode is favoured in SUSY theories • The primary decay particle K is invisible in Water Cherenkov detectors • It and the K-decay particles are visible in scintillation detectors • Better energy solution further reduces background low energy neutrino astronomy
P -> K+ nevent structure: T (K+) = 105 MeV t (K+) = 12.8 nsec K+-> m+ n (63.5 %) K+-> p+ p0 (21.2 %) T (m+) = 152 MeV T (p+) = 108 MeV electromagnetic shower E = 135 MeV m+ -> e+n n (t = 2.2 ms) p+ -> m+ n(T = 4 MeV) m+ -> e+n n (t = 2.2 ms) low energy neutrino astronomy
Conclusions LENA a new observatory complemntary to high energy neutrino astrophysics fundamental impact on e.g. geophysics, astrophysics, neutrino physics, proton decay feasibility studies very promising (Pyhäsalmi, and other places) costs ca. 100 - 200 M€ Collaborators welcome low energy neutrino astronomy