FRONTIERS OF LOW ENERGY NEUTRINO PHYSICS AND ASTROPHYSICS

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1 FRONTIERS OF LOW ENERGY NEUTRINO PHYSICS AND ASTROPHYSICS Gioacchino Ranucci - I.N.F.N. Milano TAUP 0 ROME - 5 July, Solar neutrinos and the SSM 2-Geo-neutrino detection, status and perspectives 3-Supernova neutrinos

2 Neutrino production in the Sun The pp chain reaction The CNO cycle In our star > % of the energy is created in this reaction In the Sun <1% More important in heavier stars There are different steps in which energy (and neutrinos) are produced pp ν from: pp pep 7 Be 8 B hep Monocrhomatic ν s (2 bodies in the final state) CNO ν from: 13 N 15 O 17 F

3 Neutrino production in the Sun Neutrino energy spectrum as predicted by the Solar Standard Model (SSM) John Norris Bahcall (Dec. 30, 134 Aug. 17, 2005) 7 Be: 384 kev (10%) 862 kev (0%) Pep: 1.44 MeV Surface metallicity composition controversy still open: High Z vs Low Z Villante@parallel.session linearized solar model

4 Solar neutrino experiments: a more than four decades long saga Radiochemical experiments: Homestake (Cl) Gallex/GNO (Ga) Sage (Ga) Real time Cherenkov experiments Kamiokande/Super Kamiokande SNO Scintillator experiments Borexino

5 Long standing discrepancy between measured and predicted fluxes: SNP Culminated with a crystal clear proof that neutrino oscillates SOLAR PLUS KAMLAND (Reactor ν s) Neutrino oscillations! Δm 2 = θ = Phys.Rev.Lett.101:111301,2008 MSW matter enhanced flavor conversion LMA solution

6 Given these fundamental achievements what s next? recent results and future plans from Borexino,SNO,Super Kamiokande and SAGE, Gallex/GNO note: SNO and Gallex/GNO no more operating future prospects KamLAND SNO+ LENS CLEAN, MOON, XMASS (multidisciplinary projects) Gioacchino Ranucci - I.N.F.N. Sez. di Milano Rome - 3 July, 200

7 Borexino: low energy real time detection Scintillator: 270 t PC+PPO in a 150 μm thick nylon vessel Nylon vessels: Inner: 4.25 m Outer: 5.50 m Neutrino electron scattering ν e > ν e Carbon steel plates Stainless Steel Sphere: 2212 photomultipliers 1350 m 3 Design based on the principle of graded shilding Water Tank: γ and n shield μ water Č detector 208 PMTs in water 2100 m 3 Oberauer@parallel.session 20 legs

8 Filled detector PC filling completed May 15th, 2007

9 Unprecedented intrinsic ultra lowbackground levels 232 Th: (6.8±1.5) g/g from 212 Bi- 212 Po 238 U: (1.6±0. 1) g/g from 214 Bi 214 Po nat K g/g From spectrum 85 Kr β decay- 687 kev 8 events 2±14 c/d 210 Po- α, Q=5.41 Mev quenched by 13- no evidence of 210 Bi,initially 80 c/d/t

10 BOREXINO: 12 days-free parameters: 7 Be, 14 C, CNO+ 210 Bi, 11 C, 85 Kr; -fixed at the SSM values:pp, pep 14 C 7 Be 11 C

11 4± 3 stat ± 4 syst cpd/100tons for 862 kev 7 Be solar ν Φ( 7 Βe)=(5.12 ±0.51)x10 cm -2 s -1 SSM; H.M.(5.08±0.56) x10 cm -2 s -1 L.M.(4.55 ±0.5) x10 cm -2 s -1 2 Before Borexino After Borexino Striking first confirmation of the predicted MSW transition between vacuum and matter regimes

12 Other limits obtained by Borexino after 12 days of data taking - the best in the literature 1- Limits on pp e CNO solar fluxes; with the Luminosity constraint: Φ Φ pp CNO ( Borexino data) / Φ pp ( Borexino data) / Φ ( SSM ) = ( SSM ) < 3.8 (0% C. L.) CNO 2- upper limit on the neutrino magnetic moment: μ B (0%C.L.)

13 Day night asymmetry for 7 Be solar neutrinos days total live time Night days Day days Day: Sun Altitude α >0 (zenith<0 deg) Night: Sun Altitude α<0 (zenith>0 deg) ν window ν window υ ADN = 0.02 ± stat

14 The low threshold measurement of the 8 B solar neutrinos Rate > 2.8 MeV ± Major background sources: 1) Muons; 2) Gammas from neutron capture; 3) Radon emanation from the nylon vessel; 4) Short lived (t < 2 s) cosmogenic isotopes; 5) Long lived (t > 2 s) cosmogenic isotopes ( 10 C); 6) Bulk 232 Th contamination ( 208 Tl); = ( 0.26 ± 0.04 stat 0.02 sys) counts/day 7 Be and 8 B flux measured with the same detector Borexino 8 B flux above 5 MeV agrees with existing data Neutrino oscillation is confirmed by the 8 B of Borexino at 4.2 sigma /100 tons The Borexino 8 B spectrum

15 What next for solar continue the efforts on 7 Be ν to shrink errors below 5 % (more statistics, source calibration, pep and CNO ν investigation Main problem:cosmogenic 11 C μ+ 12 C > 11 C+n+μ Muon track Spherical cut around 2.2 gamma to reject 11 C event 11 Β+e + +ν e Cylindrical cut Around muon-track n capture γ (2.2 MeV) Neutron production 14% of ν ev. are missed #Borex. Coll.Phys.Rev.C74,2006 Disentangling High Z vs Low Z SSM Peña-Garay and Serenelli arxiv: Currently the major SSM challenge

16 What next for solar possibly direct p pneutrinos observation very ambitious Potential observation window kev (electron scattered seasonal variations of the solar ν flux due to the eccentricity of the Earth s orbit kev En. more on Day/Night asym. and 8 B

17 Sudbury Neutrino Observatory 1000 tonnes D 2 O 12 m diameter Acrylic Vessel 18 m diameter support structure; 500 PMTs (~60% photocathode coverage) 1700 tonnes inner shielding H 2 O 5300 tonnes outer shielding H 2 O Urylon liner radon seal depth: 202 m (~6010 m.w.e.) ~70 muons/day

18 Neutrino Reactions in SNO CC ν e + d p + p + e NC ν + d p + n + x ν x - measures total 8 B ν flux from the Sun - equal cross section for all active ν flavors + e ES ν e ν + x x Gioacchino Ranucci - I.N.F.N. Sez. di Milano Rome - 3 July, 200

19 Three Phases of SNO Pure D 2 O Nov May 01 n + d t +γ (E γ = 6.25 MeV) PRL 87, (2001) PRL 8, (2002) PRL 8, (2002) PRC 75, (2007) Salt Jul 01 Sep 03 n + 35 Cl 36 Cl +Σγ (E Σγ = 8.6 MeV) SNO+ enhanced NC rate and separation PRL 2, (2004) PRC 72, (2005) 3 He Counters Nov 04 Nov 06 n + 3 He t + p proportional counters σ = 5330 b event by event separation PRL 101, (2008) archival papers with complete details Gioacchino Ranucci - I.N.F.N. Sez. di Milano Rome - 3 July, 200

20 SNO Fluxes: 3 Phases stat stat + syst Art MacDonald@Neutel 200 p-value for consistency of NC/CC/ES in the salt & NCD phases + D2O NC(unconstr) is 32.8%

21 φ Solar + KamLAND fit results Δm = ev B = cm s ( ± θ θ = = degrees Art MacDonald@Neutel 200 ~ 7%) deg (previous) The accuracy on θ 12 and φ 8B will improve with new data analysis: SNO LETA Recent results: SNO NCD results agree well with previous SNO phases. Minimal correlation with CC. Different systematics. New precision on θ Future solar analysis: LETA (Low Energy Threshold Analysis) 3-neutrino analysis hep flux Day-night, other variations Tomorrow morning talk..

22 SNO Low Energy Threshold Analysis Fits for Backgrounds down to 3.5 MeV A limit on θ 13 in the context of LETA analysis will be set in the global 3 ν analysis solar neutrinos from May APS meeting See tomorrow morning talk Gioacchino Ranucci - I.N.F.N. Sez. di Milano Rome - 3 July, 200

23 Super Kamiokande History inner detector mass: 32kton fiducial mass: 22.5kton SK I SK II SK III SK IV ID PMTs (40% coverage) Energy Threshold (total electron energy) SK I SK II SK III SK IV Acrylic (front) + FRP (back) 5182 ID PMTs (1% coverage) 1112 ID PMTs (40% coverage) 5.0 MeV 7.0 MeV 4.5 MeV work in progress Electronics Upgrade < 4.0 MeV target

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26 Current status SK III analysis: Most of the reconstruction tools & reduction criteria are retuned recently. The improved reconstruction of event vertex & direction leads to 10% better angular resolution compared to SK I. Currently, estimation of the systematic errors are under way. SK IV analysis: Now: 100% trigger efficiency for E total =4.5MeV. The trigger threshold will be lowered in future. SK-III-IV have already lower background level in central area in low-energy region

27 Solar ν measurements in SK III Spectrum 8 B Flux Data Best-fit Background SK-I: 2.35+/-0.02(stat)+/-0.08(sys) Angular dist. (E total = MeV) SK-I -1 SK-III 0 Central 13.3kt fiducial volume cosθ sun 1 Most of the reconstruction tools & reduction criteria are retuned recently. The improved reconstruction of event vertex & direction leads to 10% better angular resolution compared to SK-I. SK-III has lower background level in central area in low-energy region.

28 SAGE Measurement of the solar neutrino capture rate with gallium metal. 71 Ga(v,, e - ) 71 Ge, E th = 233 kev Presently SAGE is the only experiment sensitive to the pp neutrinos It has the longest almost uninterrupted time of measurements among operating solar neutrino experiments 18 year period ( ): 168 runs, 310 separate counting sets Result : (stat) 2.8 (syst) SNU or 65.4 SNU All extractions as function of time 4.1 Combined results for each year Gavrin@Physun workshop SAGE continues to perform regular solar neutrino extractions every four weeks with ~50 t of Ga

29 Ga experiments: 71 Ga(v e, e - ) 71 Ge, E th = 233 kev Measurement of the solar neutrino capture rate with gallium metal: SAGE, 50 tons of metallic 71 Ga 168 runs for the 18-year period (Jan 10 Dec 2007) give the result: (11 SNU = 1 neutrino capture/sec in a target that contains atoms of the neutrino absorbing isotope). with gallium chloride GaCl 3 solution: GALLEX, 103 tons of GaCl 3 solution containing 30 tons of natural gallium 65 runs for the 4.4-year period (May 11 Jan 17) give the result: GNO, 4.1SNU SNU SNU 103 tons of GaCl 3 acidic solution containing 30 tons of natural gallium 58 runs for the 4.7-year period (May 18 Apr 2003) give the result: (T. Kirsten, Retrospect of GALLEX/GNO, Journal of Physics: Conference Series 120 (2008) ) Combined Gallex+GNO ±5.11 SNU. SNU The weighted average of the results of all Ga experiments is now 66.1±3.1 1 SNU

30 Cr 51 Cr Ar 37 Ar Gallium chloride solution (GALLEX) (1) (2) m Ga (tons) Gallium metal (SAGE) m of target (kg) 35,5 35,5 0, enrichment (% 50 Cr) 38,6 38,6 2,4 6,4% 40 Ca (natural Ca) source specific activity (KCi/g) 0,048 0,052 1,01 2,7 source activity (MCi) 1,71 1,87 0,52 0,41 expected rate 11,7 12,7 14,0 13, R = p measured /p predicted 0.5± ± ± ±0.10 R combined 0.88 (F. Kaether, Ph. D. thesis,2007) 0.88± ± Ar (35.4 days) 51 Cr (27.7 days) 427 kev ν (.0%) 432 kev ν (0.%) 320 kev γ 747 kev ν (81.6%) 752 kev ν (8.5%) 37 Cl (stable) 813 kev ν (.8%) 811 kev ν (0.2%) 51 V

31 * The weighted average value of R is 0.87 ± 0.05, more than two SD less than unity. * If the contribution of these two excited states to the predicted rate is set to zero, then R = 0.3 ± 0.05, reasonably consistent with unity. It is believed that, although not statistically conclusive, the combination of these experiments suggests that the predicted rates is overestimated. The most likely hypothesis is that the cross sections for neutrino capture to the lowest two states in 71 Ge, both of which can be reached using either 51 Cr or 37 Ar sources, have been overestimated. J.N.Abdurashitov et al. Phys. Rev. C73, (2006) * Although there are alternative explanations based on transitions to sterile neutrinos or on quantum decoherence in neutrino oscillations. C. Giunti and M. Laveder, Mod. Phys. Lett. A 22, 24 (2007) [arxiv.org/abs/hep-ph/ ]. The source experiments with Ga Y. Farzan, T. Schwetz, and A. Yu Smirnov [arxiv.org/abs/ ]

32 TAUP 200, July 1-5, V.V. Gorbachev Conclusion New source experiment in SAGE will shed light on the problem of low result in the source experiments in gallium. For these it is necessary to make: 51 Cr neutrino source with activity 2 MCi or higher, the optimized two-zone spherical target, the measurement with accuracy 4 4.5% This is a part of future experimental program in SAGE. Gorbachev@parallel session

33 Solar Neutrino in KamLAND nuclear fusion reaction in the sun 7 Be Standard Solar Model (SSM).N. Bahcall and A.M. Serenelli, Astro. Phys. J. 621, 85 (2005) CNO purification system singles spectra after 1st purification radioactive background 1st purification GS8 AGS ~ nd purification Test low abundance of heavy element (AGS05) -10% -38% S34 : 2.5% S1,14 : 8.4% Radioactive BG reduction ( 85 Kr) : 10-4 ~10-5 after the 2nd purification

34 SNO+ $300M of heavy water removed and returned to Atomic Energy of Canada Limited (every last drop) SNO detector to be filled with liquid scintillator times more light than Čerenkov linear alkylbenzene (LAB) compatible with acrylic, undiluted high light yield, long attenuation length safe: high flash point, low toxicity cheaper than other scintillators physics goals: pep and CNO solar neutrinos, geo neutrinos, reactor neutrino oscillations, supernova neutrinos, double beta decay with Nd Gioacchino Ranucci I.N.F.N. Sez. di Milano

35 Turning SNO into SNO+ to do this we need to: buy the liquid scintillator install hold down ropes for the acrylic vessel build a liquid scintillator purification system make a few small repairs minor upgrades to the cover gas minor upgrades to the DAQ/electronics change the calibration system and sources full funding decision June 200; data taking in early 2011 a new experiment with new and diverse science goals, for modest cost Gioacchino Ranucci I.N.F.N. Sez. di Milano

36 LENS Detection Scheme e B(GT) ~0.01; Q ν =1362 e 1 B(GT) = 0.17; Q ν =114 /2 / In ( 5.7%) The Indium Low Energy Neutrino Tag τ = 6.4x10 14 y β max = 48.8 τ =231μs /2 In(p,n) (e/γ =5.7) τ = 4.76 μs 7/ / (e/γ) (e/γ = 0.6) τ =16ps 3/ γ / Sn Also IPNOS Fukuda@parallel session Unique: Specifies ν Energy E ν = E e + Q Complete LE nu spectrum Lowest Q known 114 kev access to 5.5% pp nu s Target isotopic abundance ~6% Powerful delayed coinc. Tag Can suppress bgd =10 11 x signal Downside: Bgd from 115 In radioactivity to ( pp nu s only) rate= x signal Tools: 1. Time & Space coinc. Granularity (10 7 suppression already) 2. Energy Resolution important for In betas <500 kev; Tag = 613 kev 3. Other analysis cuts

37 Normalized Absorbance Transparency of InLS 8.6 m after 8 months λ (nm) UV/Vis absorbance of zvt45 (ph 6.88) with time 10/06/05 01/23/06 03/22/06 05/31/06 Technology and Bgd Control < Towards Hi Precision fluxes > Hi Quality InLS New Detector Design Background Analysis Insights In decay bgd suppressed S/N ~3 for first time Design of Detector InLS: In content Light attenutation L(1/e) Signal Eff Pe/MeV Indium Mass(100 pp/5y) Status Cubic Lattice Chamber >8% >8m ton Total Mass 125 ton PMT s 13,300 Neutrino detection eff. 64% Raghavan@Physun workshop

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41 What s XMASS Multi purpose low-background and low-energy threshold experiment with liq. Xe Xenon detector for Weakly Interacting MASSive Particles (DM search) Xenon MASSive detector for solar neutrino (pp/ 7 Be) Xenon neutrino MASS detector (ββ decay) Solar neutrino Dark matter Double beta

42 MOON OSAKA CTU FNAL HU ICU JINR LANL UNC TU UW VNIIEF Multilayer PL plates and PL fiber planes with thin 100 Mo source film for pp-be7 solar ν and ββ with 30 mev. Detector ββ source Select ββ sources Solar ν as well A. Low Q=0.17 MeV, large CC of 680 & 220 SNU for pp & 7 Be-ν. B. Real time studies of inverse β rays in delayed coincidence with the β decays from 100 Tc. C. -units 0.27 ton 100m 3, 32 units, 1 ton 300 m Mo ν, β 100 Tc β pp, Be ν H. Ejiri, et al., PRL, 85, H. Ejiri, J. Phys. Soc. Japan H. Ejiri European Phys. J ββ 100 Mo

43 MOON PL Test module MOON-1 MOON 1 5-layers of PL plates, each with 0.53m * 0.53m * 0.01m PL. Resolution σ~3.6% at 1 MeV achieved as required. Charged current solar ν capture rate Measured by the high-resolution charge exchange reactions at RCNP Osaka : Frekers, Ejiri, Zegers et al. B(GT)~0.35, consistent with previous B(GT)=0.33, for the ground state. pp-ν 680 SNU 7 Be-ν 220 SNU, Total solar ν 1020 SNU. Only the ground state

44 Geo-neutrinos: anti-neutrinos from the Earth U, Th and 40 K in the Earth release heat together with anti-neutrinos, in a well fixed ratio: Earth emits antineutrinos whereas Sun shines in neutrinos. A fraction of geo-neutrinos from U and Th (not from 40 K) are above threshold for inverse β on protons: + Classical antineutrino detection ν+ p e + n 1.8 MeV in liquid scintillation detectors Different components can be distinguished due to different energy spectra: e. g. anti-ν with highest energy are from Uranium. Dye@parallel.session

45 Probes of the Earth s interior Deepest hole is about 12 km Samples from the crust (and the upper portion of mantle) are available for geochemical analysis. Seismology reconstructs density profile (not composition) throughout all Earth. Geo-neutrinos: a new probe of Earth's interior They escape freely and instantaneously from Earth s interior. They bring to Earth s surface information about the chemical composition of the whole planet.

46 Open questions about natural radioactivity in the Earth 1 - What is the radiogenic contribution to terrestrial heat production? 4 - What is hidden in the Earth s core? (geo-reactor, 40 K, ) 2 - How much U and Th in the crust? 3 - How much U and Th in the mantle? 5 - Is the standard geochemical model (BSE) consistent with geo-neutrino data?

47 Geo-ν: predictions of the BSE Reference Model Signal from U+Th [TNU] Mantovani et al. (2004) Fogli et al. (2005) Enomoto et al. (2005) Pyhasalmi Homestake 51.3 Baksan Sudbury Gran Sasso Kamioka Curacao 32.5 Hawaii TNU = one event per free protons per year All calculations in agreement to the 10% level Fiorentini et al. - JHep Different locations exhibit different contributions of radioactivity from crust and from mantle

48 Geo Neutrino in KamLAND prompt energy spectrum Inner tank 1,000 ton LS Outer water tank Earth Model (BSE) radiogenic heat from U, Th ~ 16 TW mass ratio (Th / U) ~ 3. analysis of component chondrite meteorite U : 8 TW Th : 8 TW K : 3 TW total : 1 TW Anti-Neutrino measurement at KamLAND (data-set 2881 ton-yr, syst. uncertainty 4.1%) TNU Model prediction 36. TNU N (U+Th)=75±27 U : 56.6 event (2.2 TNU) Th : 13.1 event (7.7 TNU) TNU (Terrestrial Neutrino Unit) = events/10 32 target-proton/year Large uncertainty (~37%), but the result is consistent with the model prediction

49 Running and planned experiments Signal [TNU] Kamioka Kamioka Sudbury Sudbury Pyhasalmi Pyhasalmi Gran Gran Sasso Sasso Baksan Baksan Homestake Homestake Curacao Curacao Mantle Crust Reactor Hawaii Hawaii Baksan Several experiments, either running or under construction or planned, have geo-ν among their goals. Figure shows the sensitivity to geo-neutrinos from crust and mantle together with reactor background. Homestake

50 Borexino at Gran Sasso A 300-ton liquid scintillator underground detector, running since may Signal, mainly generated from the crust, is comparable to reactor background. From BSE expect 5 7 events/year for 80% eff. and 300 tons C H 12 fiducial mass In about 700 days of data should get 3σ evidence of geo-neutrinos. Signal [TNU] R C M

51 Geoneutrinos in SNO+ antineutrino events ν e + p e + + n: KamLAND: 33 events per year (1000 tons CH 2 ) / 142 events reactor SNO+: 44 events per year (1000 tons CH 2 ) / 38 events reactor spectral dip is due to oscillation of neutrinos from reactors 240 km away! spectrum of antineutrino events in SNO+

52 Hanohano a mobile deep LENA, ocean detector 10 kiloton liquid scintillation Deploy and retrieve from barge 100 kton-scale scintillator detector concepts

53 Supernova Detection session session

54 History of supernova detectors BAKSAN (330t liq.sci.) IMB (7000t water) LVD ( t liq. sci.) Super-Kamiokande (32000t water) Amanda/IceCube Borexino(300t liq.sci.) SN187a Kamiokande (2140t water) SNO (1000t D 2 O) KamLAND(1000t liq.sci.) Detectors in the world have been monitoring galactic supernova for almost 30 years. Detectors in the world have been monitoring galactic supernova for almost 30 years. LSD(0t liq. sci.) Mini-BOONE (700t liq.sci.) Macro

55 Supernova detectors in the world (running and near future experiments) Super-K Borexino LVD Baksan SNO+ KamLAND (beginning construction) HALO (proposed) Mini-BOONE IceCube NOνA (construction started) Icarus 600 (in construction)

56 LVD detector LVD consists of an array of 840 counters, 1.5 m 3 each. Total target: 1000 t of C n H 2n 00 t of Fe 4MeV threshold With <1MeV threshold for delayed signal (neutron tagging efficiency of %) E resolution: 13%(1σ) at 15MeV ~300 ν e p e + n events expected for 10 kpc SN. At Gran Sasso Lab.

57 LVD on-line sensitivity W.Fulgione, poster #0 LVD can select burst candidates on-line, with low model-dependence and with severe noise rejection factors. N.Yu. Agafonova et al. Astroparticle Physics, Vol 28/6 pp in press- LVD can identify, on-line, ν-bursts occurring in the whole Galaxy (D<20 kpc) with efficiency > 0%. Such a sensitivity is preserved even if the detector is running with only 1/3 of its total mass and stand-alone, with a severe noise rejection factor (<1 fake event/100 years). The on-line trigger efficiency can be extended up to 50 kpc by introducing a cut on the visible energy at 10 MeV. STANDALONE SNEWS (<1 fake /100 years) (<1 fake /1month) E cut =10 MeV E cut =10 MeV E cut =7 MeV E cut =7 MeV

58 Super-K: Expected number of events Neutrino flux and energy spectrum from Livermore simulation (T.Totani, K.Sato, H.E.Dalhed and J.R.Wilson, ApJ.46,216(18)) ~7,300 ν e +p events ~300 ν+e events ~ O NC γ events ~ O CC events (with 5MeV thr.) for 10 kpc supernova ~5 degree pointing accuracy

59 IceCube: The Giga ton Detector Array IceTop Design Specifications InIce Fully digital detector concept Number of strings 75 Number of surface tanks 160 Number of DOMs 4820 Instrumented volume 1 km 3 Angular resolution < 1.0 AMANDA 1 Strings 677 Modules AMANDA construction: IceCube construction: Supernova neutrinos coherently increase the PMT signal rate.

60 Single volume liq. scintillator detectors KamLAND Borexino SNO+ 300ton liq.sci. Running since ton liq.sci. Running since ton liq.sci. completing final design and beginning initial construction. 700ton liq.sci. Running since 2004.

61 Liquid scintillator detectors Expected number of events(for 10kpc SN) Events/1000 tons Inverse beta( ν e +p e + +n) : ~300 events Spectrum measurement with good energy resolution, e.g. for spectrum distortion of earth matter effect. CC on 12 C(ν e + 12 C e+ 12 N( 12 B)) : ~30 events Tagged by 12 N( 12 B) beta decay Electron scattering (ν+e - ν+e - ) : ~20 events NC γ from 12 C(ν+ 12 C ν+ 12 C+γ): ~60 events Total neutrino flux, 15.11MeV mono-energetic gamma ν+p scattering( ν+p ν+p): ~300 events Spectrum measurement of higher energy component. Independent from neutrino oscillation.

62 SuperNova Early Warning System snews.bnl.gov Details: arxiv:astro-ph/ Individual supernova-sensitive experiments send burst datagrams to SNEWS coincidence computer at Brookhaven National Lab(backup at U. of Bologna) alert to astronomers if coincidence in 10 seconds Participating experiments: arxiv: session Super- Kamiokande (Japan) Large Volume Detector (Gran Sasso) AMANDA/ IceCube (South Pole) Borexino (Gran Sasso)

63 Conclusions Low energy neutrino physics and astrophysics is a field that, despite the many successes already accumulated, is promising for the future many more exciting results Solar neutrino investigation is reaching the stage in which the precise spectroscopy of the whole low energy spectrum is a real possibility, up to a level that makes it feasible the check of the SSM, hence paving the path for resolving the discrepancy between high Z and low Z models An entire new area of investigation is represented by the Geoneutrinos study, which exploits the more powerful detectors aimed at the solar neutrino detection to open a completely new window on the mysteries of the interior of the Earth Supernova neutrino experiments are already a powerful large family with new members expected to join in the near future, and hence if Nature will arrange for us a galactic firework, surely we will not miss the fun! Acknowledgements to (in addition to the people cited throughout the talk) M.Nakahata, V. Gavrin, R, Raghavan, D. McKinsey, M. Chen, A, Sukuzi, T. Kirsten, Y. Suzuki, E. Ejiri, G. Fiorentini