Sterile neutrinos in Icarus and Borexino. Paola Sala (Icarus) Gioacchino Ranucci (Borexino) INFN Milano

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1 Sterile neutrinos in Icarus and Borexino Paola Sala (Icarus) Gioacchino Ranucci (Borexino) INFN Milano Milano

2 Outline Neutrino oscillations and hints of sterile neutrinos. The ICARUS-NESSIE Proposal at the CERN- SPS short baseline neutrino facility Short Distance Neutrino Oscillations with BoreXino - SOX Milano Slide# : 2

Being the only elementary fermions whose basic properties are still largely unknown, neutrinos must naturally be one of the main priorities to complete

3 The new physics frontier The discovery of a Higgs boson at CERN/LHC has crowned the success of the Standard Model (SM). Neutrino masses and oscillations represent today a main experimental evidence of a potentially unknown physics beyond the Standard Model. Being the only elementary fermions whose basic properties are still largely unknown, neutrinos must naturally be one of the main priorities to complete our knowledge of the SM. A candidate event in the search for the Higgs boson, showing two electrons and two muons (Image: CMS/CERN) The first CNGS neutrino event in ICARUS Milano Slide# : 3

4 Neutrinos: a golden field for astro-particle physics Neutrinos have been the origin of an impressive number of Surprises : Masses, once zero by ignorance, are actually important Oscillations extend and complete the C+KM quark mixing Oscillations due to matter exist But this is not all! Important discoveries may be ahead: CP violation in the lepton sector Majorana or Dirac s; -less -decay, -masses Sterile neutrino and other surprises Right handed neutrinos and see-saw mechanisms The cosmological importance of neutrinos is immense Milano Slide# : 4

5 Neutrino flavors and oscillations So far, 3 neutrino flavors Combination of 3 mass eigenstates 3 mixing angles 2 mass differences 1 CP phase neutrino Oscillations In 2 flavors approximation: e P ( ) = sin 2 (2 ) sin 2 (1.27Dm 2 L (m) /E (MeV ) <-> e <-> INFN-CTS_march 2013 Slide# : 5

6 Known oscillation parameters Solar and reactor e, e disappearance : Davis, KamLand, SNO, Borexino Dm 2 12= Dm 2 solar =O (MeV) /O (100 km) 8 x 10-5 ev 2 sin Atmospheric and accelerator disappearance, : SuperKamiokande, Minos, Opera and CNGS, T2K Dm 2 23= Dm 2 atm =O (GeV) /O (1000 km) 2.4 x 10-3 ev 2 sin Accelerator e, reactor e disapp. : DayaBay, Reno, T2K sin Mass Hierarchy and mass values are unknown CP is unknown From Z 0 width : only 3 active neutrinos However: Milano Slide# : 6

7 Some unexplained -> e events: The LNSD Anomaly L/E 1 Milano Slide# : 7

The MiniBooNE experiment at FNAL (1998-today)

8 The MiniBooNE experiment at FNAL (1998-today) L/E 1 Primary beam : 8 GeV/c protons Neutino beam 1 GeV or. Distance 500 m An event excess of 78.4±28.5 events (2.8σ) is observed for anti-. Low energy excess of 162.0±47.8 events (3.4σ) in neutrino mode INFN-CTS_march 2013 Slide: 8

9 LSND-like exclusion from the present ICARUS experiment allowed MiniBooNE allowed LSND 90% allowed LSND 99% Eur. Phys. J. C 73 (2013) limit of KARMEN present ICARUS exclusion area ICARUS result strongly limits the window of parameters for a possible LSND anomaly to a very narrow region (Dm ev 2 and sin ) where there is an overall agreement (90% CL) of Milano the present ICARUS limit the limits of KARMEN the positive signals of LSND and MiniBooNE Slide# : 9

The Gallium and reactor disappearance anomaly Recent re-evaluation of reactor antineutrino spectra The ratio R between the observed and predicted rates of previous experiments is decreased to R = 0.

10 The Gallium and reactor disappearance anomaly Recent re-evaluation of reactor antineutrino spectra The ratio R between the observed and predicted rates of previous experiments is decreased to R = ± 0.023, 3.0 from unity. SAGE and GALLEX experiments recorded the calibration signal produced by intense artificial k- capture sources of 51 Cr and 37 Ar. The ratio R between the detected and predicted neutrino rates are consistent : R = (0.86 ± 0.05), about 2.7 from R=1 Can be fitted with neutrino oscillations around Dm 2 new 2 ev 2 and sin 2 (2 new ) 0.3. Milano Slide# : 10

11 Over-all evidence is mounting. Planck? Combined evidence for some possible anomaly at 1 ev 2 : Could be the hint for the existence of one or more- additional neutrino? Milano Slide# : 11

What are sterile neutrinos? Sterile neutrinos are a hypothetical type of neutrinos that do not interact via any of the fundamental interactions of the Standard Model except gravity.

12 What are sterile neutrinos? Sterile neutrinos are a hypothetical type of neutrinos that do not interact via any of the fundamental interactions of the Standard Model except gravity. The name was coined in 1957 by Bruno Pontecorvo. If they are heavy enough, they may also contribute to cold dark matter or warm dark matter. Bruno Pontecorvo Sterile neutrinos may mix with ordinary neutrinos Oscillations into sterile neutrinos are detected as disappearance of ordinary neutrinos (reactors, Gallex anomalies) Oscillations sterile detected as appearance (LSND) Milano Slide# : 12

13 A search for sterile neutrino :ICARUS-NESSIE at CERN A new neutrino beam for a short base-line (L/E 1) experiment The experimental set-up will include a FAR and a NEAR detectors, identical except for dimensions In absence of oscillations, apart some beam related small spatial corrections, the two spectra at different distances should a precise copy of each other, The ICARUS Liquid Argon Time Projection chamber technology will allow for high precision, low background oscillation study Magnetic spectrometers (NESSIE collab.) will be installed in far and near position for μ disappearance searches This will presumably permit a definitive clarification of the LNSD anomaly in all the available oscillation channels in the same experiment. ICARUS-NESSIE proposal, SPSC-P-347, arxiv: Slide# : 13

14 New CERN SPS 2 GeV neutrino facility in North Area 100 GeV primary proton beam fast extracted from CERN-SPS in North Area: C-target station + two magnetic horns, ~110 m decay pipe, beam dump followed by stations. Interchangeable and focussing. Far position (1600 m) ICARUS-T600 detector + magnetic spectrometer Near position (460 m) 150t LAr-TPC detector to be build anew + magnetic spectrometer Slide# : 14

3D spatial reconstruction from stereoscopic

Collection plane signals Collection (top

15 ICARUS LAr-TPC detection technique 2D projection for each of 3 wire planes per TPC 3D spatial reconstruction from stereoscopic 2D projections charge measurement from Collection plane signals Collection (top view) Induction 2 (top view) Induction 1 (frontal view) CNGS charge current interaction, one of TPC s shown Neutrino Telescopes, March

cathode ICARUS @ LNGS: the first LARGE LAr-TPC 1.

per module) LAr active mass 476 t: (17.9 x 3.1 x 1.5 for each TPC) m 3 ; drift length = 1.5 m; E drift = 0.5 kv/cm; v drift = 1.

16 cathode LNGS: the first LARGE LAr-TPC 1.5m Hall B cryogenics (behind) LN 2 vessels readout electronics E E T300 T300 readout wire arrays T300 module: two TPCs with the common cathode Two identical T300 modules (2 TPC chambers per module) LAr active mass 476 t: (17.9 x 3.1 x 1.5 for each TPC) m 3 ; drift length = 1.5 m; E drift = 0.5 kv/cm; v drift = 1.6 mm/ms 3 readout wire planes at 0, ±60, 3mm plane spacing (for each TPC chamber): wires, 3 mm pitch 2 Induction planes, 1 Collection PMT for scintillation light (128 nm): (20+54) PMTs trigger and t 0 Total energy reconstruction of events from charge integration. Full sampling, homogeneous calorimeter; excellent accuracy for contained events. Neutrino Telescopes, March

17 T600 in hall B (CNGS2-2009) INFN-CTS_march 2013 Slide: 17

18 The ICARUS Collaboration M. Antonello 1, B. Baibussinov 5, V. Bellini 22,23, H. Bilokon 6, F. Boffelli 8, M. Bonesini 9, E. Calligarich 8, N. Canci 1, S. Centro 4,5, A. Cesana 10, K. Cieslik 11, D. B. Cline 12, A. G. Cocco 14, D. Dequal 4,5, A. Dermenev 16, R. Dolfini 7,8, C. Farnese 4, A. Fava 5, A. Ferrari 17, G. Fiorillo 13,14, G. T. Garvey 18, F. Gatti 2,3, D. Gibin 4,5, S. Gninenko 16, F. Guber 16, A. Guglielmi 5, M. Haranczyk 11, J. Holeczek 19, A. Ivashkin 16, M. Kirsanov 16, J. Kisiel 19, I. Kochanek 19, A. Kurepin 16, J. Łagoda 20, G. Lucchini 9, W. C. Louis 18, F. Mammoliti 22,23, S. Mania 19, G. Mannocchi 6, S. Marchini 5, V. Matveev 16, A. Menegolli 7,8, G. Meng 5, G. B. Mills 18, C. Montanari 8, M. Nicoletto 5, F. Noto 22,23, S. Otwinowski 12, T. J. Palczewski 20, G. Passardi 17, A. Pepato 5, F. Perfetto 13,14, P. Picchi 6, F. Pietropaolo 5, P. Płonski 21, R. Potenza 22,23, A. Rappoldi 8, G. L. Raselli 8, M. Rossella 8, C. Rubbia 1,17, P. Sala 10, A. Scaramelli 10, E. Segreto 1, D. Stefan 1, J. Stepaniak 20, R. Sulej 20, C.M. Sutera 22, O. Suvorova 16, M. Terrani 10, D. Tlisov 16, R. G. Van de Water 18, G. Trinchero 6, M. Turcato 5, F. Varanini 4, S. Ventura 5, C. Vignoli 1, H. G. Wang 12, X. Yang 12, A. Zani 8, K. Zaremba INFN, LNGS, Assergi (AQ), Italy 2. Dipartimento di Fisica, Università di Genova, Genova, Italy 3. INFN, Sezione di Genova, Genova, Italy 4. Dipartimento di Fisica, Università di Padova, Padova, Italy 5. INFN, Sezione di Padova, Padova, Italy 6. INFN, LNF, Frascati (Roma), Italy 7. Dipartimento di Fisica Nucleare e Teorica, Università di Pavia, Pavia, Italy 8. INFN, Sezione di Pavia, Pavia, Italy 9. INFN, Sezione di Milano Bicocca, Dipartimento di Fisica G. Occhialini, Milano, Italy 10. INFN, Sezione di Milano e Politecnico, Milano, Italy 11. The Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Science, Kraków, Poland 12. Department of Physics and Astronomy, University of California, Los Angeles, USA 13. Dipartimento di Scienze Fisiche, Università Federico II, Napoli, Italy 14. INFN, Sezione di Napoli, Napoli, Italy 16. INR-RAS, Moscow, Russia 17. CERN, Geneva, Switzerland 18. Los Alamos National Laboratory, New Mexico, USA 19. Institute of Physics, University of Silesia, Katowice, Poland 20. National Center for Nuclear Research, Warszawa, Poland 21. Institute for Radioelectronics, Warsaw University of Technology, Warsaw, Poland 22. INFN, Sezione di Catania, Catania, Italy 23. Dipartimento di Fisica e Astronomia, Università di Catania, Catania, Italy

19 ICARUS in the CNGS beam CNGS : mainly, E 20 GeV L =732 km Shut down dec Icarus since 2010: detector live-time > 93% Superluminal searches (P. L. B711 (2012) 270, P. L. B713 (2012), JHEP 11 (2012) 049) e LSND/MiniBooNE anomaly (Eur. Phys. J. C (2013)) Milano 4-Apr-2013 Slide# : 19

5089) 3D object driven by optimization of its 2D projections (no need for drift

20 Precise particle tracking and identification primary vertex CNGS beam cathode Induction kaon New 2D => 3D approach for LAr TPC (in press: AHEP, arxiv: ) 3D object driven by optimization of its 2D projections (no need for drift matching) Collection 3D reconstruction p K de/dx based PID μ Milano Slide# : 20

Run 9927 Event 572: -CC CNGS event Total visible energy 4.5 GeV close-up of two e.m.

decay is observed Induction2 0 Conversion distances 6.9 cm, 2.3 cm Track 1 ( ) 2 3 (p) Sec.

21 Run 9927 Event 572: -CC CNGS event Total visible energy 4.5 GeV close-up of two e.m. showers Primary vertex (A): Collection 3D very long (1), e.m.cascades(2), (3) Secondary vertex (B): the longest track (5) is a coming from stopping k (6). decay is observed Induction2 0 Conversion distances 6.9 cm, 2.3 cm Track 1 ( ) 2 3 (p) Sec. vtx. 4 5 ( ) 6 (K) 7 E dep [MeV] cosx B cosy A cosz

22 e/g separation: de/dx in cascade initial part E g = 102 ± 10 MeV θ o reconstruction: pπ o = 912 ± 26 MeV/c mπ o = 127 ± 19 MeV/c² θ = 28.0 ± 2.5º MC: single electrons (Compton) MC: e+ e pairs (g conversions) data: EM cascades (from 0 decays) 2 m.i.p. E g = 685 ± 25 MeV Collection ~0.02 X0 sampling; g s separated from vtx; g rejection increases with energy; e selection efficiency const with energy; 1 m.i.p. 1 m.i.p. MC 2 m.i.p. INFN-CTS_march Venice_March Slide# : 22

Main differences with respect to the LNSD experiment are: L/E ~ 1 m/mev at LNSD, but L/E 36.

23 A new result : LNSD search at CNGS CNGS facility delivers an almost pure beam at 730 km peaked in the range 10 E 30 GeV (beam associated e about 1/2%) looking visually for the signature of a e signal. Main differences with respect to the LNSD experiment are: L/E ~ 1 m/mev at LNSD, but L/E 36.5 m/mev at ICARUS E oscillation signal averages to sin 2 (1.27Dm 2 new L /E) ~1/2 and <P> e ~ ½ sin 2 (2 new ) INFN-CTS_march 2013 An initial electron progressively transforming into a shower in Lar-TPC Slide# : 23

The ICARUS T600 as Far detector T600 will

decommissioning at LNGS, ensuring the new

number of components will be disassembled

in new vessels and new external insulation

24 The ICARUS T600 as Far detector T600 will be transported to CERN in 2013, after decommissioning at LNGS, ensuring the new experiment operation again in 2016 A large number of components will be disassembled and transported: inner detectors, electronics, ancillary systems, LN2 liquefaction system TPC s will be inserted in new vessels and new external insulation Near detector : T150 (1/4 T600): INFN-CTS_march 2013 Slide# : 24 Slide: 24

25 Expected signals for LSND/MiniBooNE anomalies Event rates in the near (330 m) and far (1600 m) LAr detectors for pot. Oscillated signals clustered below 6 GeV of visible energy. All beam-line parameters still under optimization (including the new near position at 460 m) negative focusing positive focusing NEAR FAR NEAR FAR + anti- (LAr) 2030 K 270 K 5250 K 670 K e + anti- e (LAr) 35 K 4.2K 54 K 6.4 K sin 2 (2 )=0.96, Dm 2 =0.064 ev sin 2 (2 )=0.02, Dm 2 =0.4 ev sin 2 (2 )=0.002, Dm 2 =2 ev sin 2 (2 )=0.0066, Dm 2 =4.42 ev K 2400 Slide# : 25

26 A possible expectation of LSND mass and mixing angle Events rates shown both for [background] and [oscill.+background] at d=330 m and d=1600 m and the optimal predictions from ICARUS et al. Dm 2 = 0.4 ev 2, sin 2 (2 ) = 0.01 For d=1.6 km, E < 5 GeV and pot (1 y) a e oscillation signal of 1200 events is expected above 5000 backgr. events T150 near detector T600 far detector INFN-CTS_march 2013 Slide# : 26

Exploring all channels: expected sensitivity e-appearance: 1 year μ beam (left) 2 year anti μ beam (right) for 4.5 10 19 pot/year, 3% syst. uncertainty on energy spectrum.

27 Exploring all channels: expected sensitivity e-appearance: 1 year μ beam (left) 2 year anti μ beam (right) for pot/year, 3% syst. uncertainty on energy spectrum. LSND allowed region is fully explored in both cases μ e μ e e e e/ -disappearance: 1 year μ INFN-CTS_march 2013 combined anomalies : from reactor s, Gallex and Sage experiments. Slide# : 27

28 Time Schedule (ICARUS) INFN-CTS_march years Slide 28

29 Thank you! INFN-CTS_march LNGS_May Slide 29

Recent Planck 2013 results from Big Bang cosmology A cosmologic search for additional neutrino-like relativistic particles beyond the three families of neutrinos in the standard model has been

30 Recent Planck 2013 results from Big Bang cosmology A cosmologic search for additional neutrino-like relativistic particles beyond the three families of neutrinos in the standard model has been reported by the Planck collaboration N eff = 3.36 ± (95%; Planck+WP+highL) N eff = 3.30 ± (95%; Planck+WP+highL+BAO) N eff = 3.52 ± (95%; Planck+WP+highL+H0+BAO) We conclude that the tension between direct H0 measurements and the CMB and BAO data in the base Λ CDM can be relieved at the cost of additional neutrino-like physics This demonstrates the extreme complexity of the situation N=3 N=4 INFN-CTS_march 2013 Slide# : 30

ICARUS at FNAL: a proposal. Carlo Rubbia, GSSI INFN, Italy

ICARUS at FNAL: a proposal. Carlo Rubbia, GSSI INFN, Italy ICARUS at FNAL: a proposal Carlo Rubbia, GSSI INFN, Italy PAC_FNAL 23 January 2014 1 The ICARUS Collaboration M. Antonello 1, B. Baibussinov 2, V. Bellini 4,5, H. Bilokon 6, F. Boffelli 7, M. Bonesini