Experimental neutrino physics: natural beams, reactors and LBL Barbara Caccianiga-INFN Milano EPS- Conference on High Energy Physics 2015 22-29 July 2015 Vienna Neutrino Physics: the puzzle-making 2 Neutrino Physics: the puzzle-making Dm2 n2 12 2 Dm 13 3 Neutrino Physics: the puzzle-making q ~9o o 13 o ne q23~45 q12~33 n1 The Pontecorvo-Maki-Nakagawa-Sakata (PMNS) Matrix i n e 1 0 0 Dc13m2 0 s13e c12 s12 0 n1 n 12 n 0 c s 8x100 -5eV21 0 sn2 c 0 n 23 23 12 12 2 i n 0 s23 c23 s13e 0 c13 0 0 1 n 3 Dm2 13 n n 3x10-3eV2 3 44 Experimental neutrino physics: the puzzle making To complete the neutrino puzzle • Perform appearance and/or disappearance experiments using different neutrino sources and baselines; E n L n source n DETECTOR • Characteristic E/L sets the reach of the experiment in term of Dm2; • The possibility of probing different E/L within the same experiment allows to see the oscillatory pattern of appearance or disappearance thus enhancing sensitivity; 5 Experimental neutrino physics: the puzzle making To complete the neutrino puzzle • Perform appearance and/or disappearance experiments using different neutrino sources and baselines; E n L n source n DETECTOR Oscillations in vacuum (2 flavours) 2 Δmxy L P(ν ν )~sin 2 2θ sin 2 2 x y xy • Depends on E, L, Dm , q 4E 6 Experimental neutrino physics: the puzzle making To complete the neutrino puzzle • Perform appearance and/or disappearance experiments using different neutrino sources and baselines; E n L n source n DETECTOR Oscillations in matter (2 flavours) • Resonant effects for neutrinos 2 crossing matter; 2 M 2 (Δmxy )M L 2 P(νx νy )~sin 2θxy sin • Depends on E, L, Dm (also on 4E its sign!), q and r; 7 Experimental neutrino physics: the puzzle making To complete the neutrino puzzle • Perform appearance and/or disappearance experiments using different neutrino sources and baselines; E n L n source n DETECTOR Oscillations in matter (3 flavours) 2 • Depends on E, L, Dm ij, qi, CP.,.. 8 Experimental neutrino physics: the puzzle making To complete the neutrino puzzle • Perform appearance and/or disappearance experiments using different neutrino sources and baselines; E n L n source n DETECTOR NEUTRINO SOURCES - Natural sources (solar, atmosferic neutrinos) - Reactor neutrinos - Accelerator neutrinos (Long Baseline) 9 Experimental Neutrino Physics: the puzzle-making The Pontecorvo-Maki-Nakagawa-Sakata (PMNS) Matrix cij cosqij sij sinqij i n e 1 0 0 c13 0 s13e c12 s12 0 n1 n 0 c23 s23 0 1 0 s12 c12 0 n 2 atmosferic n SBL reactor n solar n accelerator in LBL reactor n n 0accelerator s23 n c23 s13e 0 c13 0 0 1 n 3 NEUTRINO SOURCES - Natural sources (solar, atmosferic neutrinos) - Reactor neutrinos - Accelerator neutrinos (Long Baseline) 10 Natural beams • Solar neutrinos • Atmosferic neutrinos 11 Natural beams Solar neutrinos E~ 1 MeV L~ 1011 m The Sun is powered by nuclear reactions which produce neutrinos pp CYCLE: ~99% of the sun energy CNO CYCLE: <1% of the sun energy Natural beams Solar neutrinos E~ 1 MeV L~ 1011 m E/L ~ 10-11 eV2 N.B.: resonance due to matter effects for E>1 MeV 2 ne disappearance: sensitive to (Dm )12+ q12 i n e 1 0 0 c13 0 s13e c12 s12 0 n1 n 0 c s 0 1 0 s c 0 n 23 23 12 12 2 i n• L is set0 by Nature,s23 c cannot23 be schanged;13e 0 c13 0 0 1 n 3 • Investigating different solar neutrino from different reactions it is possible to probe P(ne ne) as a function of E; Natural beams Solar neutrinos • I recall that the Solar Neutrino Problem was the first hint towards nu oscillations • Huge detectors based on hundreds/thousands of tons of detecting material Homestake Borexino Superkamiokande Gallex/SAGE SNO Natural beams Solar neutrinos Cerenkov Clorine Scintillator Gallium 15 Natural• Barbara beams Caccianiga -INFN Milano 50th Rencontres de Moriond- La Thuile, March 14th 21st 2015 Borexino: Nature 512, 383-386 (2014) observation of pp neutrinos (6.6 0.7)1010 cm-2s1 measured 10 -2 1 pp (5.98 0.04)10 cm s expected (high - Z) (6.03 0.04)1010 cm-2s1 expected (low - Z) Luminosity in neutrinos consistent with luminosity in photons Natural beams Solar neutrinos+KamLAND KamLAND+SOLAR 2 arXiV: 1409.4515 combined results on (Dm )12+ q12 Results from solar and KamLAND Survival probability P(ne ne) 2 0.18 5 2 Dm12 7.530.18 10 eV 2.3% precision 2 0.029 tan q12 0.4360.025 6.6% precision Oscillations Oscillations in vacuum in matter Natural beams Solar neutrinos+KamLAND What Next? Small tension (~2s ) in Dm2 between solar and KamLAND data Gonzales-Garcia,Maltoni,Schwetz . arXiV: 1409.5439 Tension comes from 1) no up-turn seen in the 8B spectrum so far; 2) indication for a non vanishing D/N asymmetry in SK; Non-standard interactions and super-light sterile neutrino? arXiV:1101.3875, arXiV:1307.3092, arXiV:1012.5627 Study transition region between vacuum and matter oscillation regime Natural beams Atmosferic neutrinos E~ 1 GeV L~ 104-107 m Secondary products of cosmic rays in the atmosphere ne, anti- ne, n, anti- n; BASELINE L ENERGY selecting q is equivalent to select L Natural beams Atmosferic neutrinos E~ 1 GeV L~ 104-107 m E/L ~ 10-3 eV2 n , anti- n disappearance 2 sensitive to (Dm )23+ q23 ne , anti- ne appearance First evidence of oscillations in this sector! Y. Fukudae (Super-Kamiokande Collaboration) et al. (1998). "Evidence for Oscillation of Atmospheric Neutrinos". Physical Review Letters 81 (8): 1562–1567. Natural beams Atmosferic neutrinos and neutrino mass hierarchy • Matter effects introduce a dependence on the sign of Dm2 and on the sign of A, where for n and anti- n respectively (Dm2 )m L PM (ν ν ) PM (ν ν ) sin 2θ sin 2 2θmsin 2 13 e μ μ e 23 13 4E sin22θ sin22θm 13 13 2 2 2G N E sin22q cos2q F e • resonance occurs when 13 13 Δm2 13 2 2 Dm13 cos(2q13 ) 2 2GF Ne E 2 2G N E (Dm2 )m Δm2 sin22q cos2q F e 13 13 13 13 Δm2 13 • This condition is met when E~30 GeV/r [g cm-3] for 1 GeV<E<20 GeV Natural beams Atmosferic neutrinos and neutrino mass hierarchy P(n n ) • Map upward n flux in bins Normal Hierarchy Inverted Hierarchy of (E,cosq); • cosq= -1 L~12000 Km; Letter of Intent PINGU- arXiV:1401.2046 Natural beams Atmosferic neutrinos and neutrino mass hierarchy P(anti-n anti-n ) Inverted Hierarchy Normal Hierarchy Note that: P(n n ) in NH P(n n )in IH • If it is not possible to distinguish between n and anti-n the effect of hierarchy washes out; • Fortunately s (n ) s (n ) and (n ) (n ) possible to see a few % effect due to hierarchy Letter of Intent PINGU- arXiV:1401.2046 Natural beams Atmosferic neutrinos and neutrino mass hierarchy • In the framework of IceCube and Km3NET; • Instrument ~ Mtons of ice (PINGU) or sea-water (ORCA) • Fine granularity to have low threshold; PINGU ORCA ..or alternatively use a magnetized 50 kton detector which is capable of distinguishing neutrinos from anti-neutrinos (INO project).. Natural beams Reactor neutrinos 25 Reactors Reactor neutrinos Reactor neutrinos: anti- ne mainly coming from the beta-decay of the fission products of 235U, 238U, 239Pu and 241Pu; E~ 5 MeV Detecting reaction: 3- 5 inverse beta decay L~ 10 10 m • CRITICAL: Systematics associated to the reactor n spectrum (depending on the fuel composition) Near and far detector; Reactors Reactor neutrinos antine disappearance Dm2 L Dm2 L Dm2 L 2 2 2 13 2 2 23 4 2 2 12 P(n e n e ) 1 sin 2q13 cos 2q12 sin sin 2q12 sin cos q13 sin 2q12 sin 4E 4E 4E Daya Bay ~60 km ~180 km JUNO KamLAND L ~ 180 Km 2 sensitive to (Dm )12+ q12 (solar term) Reactors Reactor neutrinos antine disappearance Dm2 L Dm2 L Dm2 L 2 2 2 13 2 2 23 4 2 2 12 P(n e n e ) 1 sin 2q13 cos 2q12 sin sin 2q12 sin cos q13 sin 2q12 sin 4E 4E 4E Daya Bay 2 2 2 Dmee L ~60 km sin 2q sin ~180 km 13 4E JUNO KamLAND L ~ 1.5 Km 2 sensitive to (Dm )13+ q13 Reactors Reactor neutrinos: Double-Chooz, RENO and Daya-Bay Double Chooz: • so far results only with the far detector • near detector takes data since dec 2014 (first results with both detectors by end of 2015) Daya-Bay: deeper, higher nuclear plant power, more far/near detectors, more favourable baseline; Reactors Reactor neutrinos: results on q13 RESULTS FROM DAYA-BAY (Moriond 2015) • Best precision on q13 measurement (~6%) 2 0.005 sin 213 0.0840.005 2 0.10 3 2 Δmee 2.440.11 10 eV χ 2/NDF 134.7/146 Reactors Reactor neutrinos antine disappearance Dm2 L Dm2 L Dm2 L 2 2 2 13 2 2 23 4 2 2 12 P(n e n e ) 1 sin 2q13 cos 2q12 sin sin 2q12 sin cos q13 sin 2q12 sin 4E 4E 4E Daya Bay ~60 km JUNO ~180 km KamLAND L ~ 60 Km sensitive to mass hierarchy Reactors Reactor neutrinos: the JUNO proposal antine disappearance Dm2 L Dm2 L Dm2 L 2 2 2 13 2 2 23 4 2 2 12 P(n e n e ) 1 sin 2q13 cos 2q12 sin sin 2q12 sin cos q13 sin 2q12 sin 4E 4E 4E Daya Bay ~60 km JUNO ~180 km Exploit interference in KamLAND n oscillations between atmospheric and solar term; • It is feasible because q13 is relatively large! • Unlike accelerator or atmosferic experiments this technique doesn’t depend on CP and q23 ; Reactors Reactor neutrinos: the JUNO proposal antine disappearance Dm2 L Dm2 L Dm2 L 2 2 2 13 2 2 23 4 2 2 12 P(n e n e ) 1 sin 2q13 cos 2q12 sin sin 2q12 sin cos q13 sin 2q12 sin 4E 4E 4E Exploit interference in n oscillations between atmospheric and solar term; Requires exceptional energy resolution Reactors Reactor neutrinos: the JUNO proposal Precision < 1% ! Civil construction: 2015-2017; Detector Installation:2016-2019; Filling and