NEUTRINOS FROM CERN TO GRAN SASSO: THE CNGS PROJECT

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1 NEUTRINOS FROM CERN TO GRAN SASSO: THE CNGS PROJECT Marcos Dracos IPHC-IN2P3/CNRS, Strasbourg 1

Neutrino Oscillations and the CNGS project MNSP Matrix (Maki, Nakagawa, Sakata, Pontecorvo) Ue1 Ue2 Ue3 U = Uμ1 Uμ2 Uμ3 cij = cos θij, sij = sinθij U 1 U 2 U τ τ τ3 i CP c12 s12 0 1 0 0 c13 0 e δ s

2 Neutrino Oscillations and the CNGS project MNSP Matrix (Maki, Nakagawa, Sakata, Pontecorvo) Ue1 Ue2 Ue3 U = Uμ1 Uμ2 Uμ3 cij = cos θij, sij = sinθij U 1 U 2 U τ τ τ3 i CP c12 s c13 0 e δ s iα 2 /2 = s12 c c23 s e 0 iδcp iα3 / s23 c 23 e s1 3 0 c e solar, reactors atmospheric, Majorana reactors accelerators accelerators phases CP violation 2+ iδ Δm 2 21 = ev 2 sin θ 12 = (~ 34 ) Δm 2 32 = ev 2 sin θ 23 = (~ 43 ) sin 2 θ (< 12.4 ) 2

3 Long-Baseline Experiments Present Long-Baseline Projects in the atmospheric oscillation region 732 km MINOS Numi ν μ beam Fermilab-Minessota 730 km Disappearance experiment (precise measurements of Δm 2 23 and θ 23 ) CNGS ν μ beam CERN-Gran Sasso 732 km First Appearance project 3

4 CERN Beam Facilities CNGS 4

5 CNGS 5

6 CNGS Layout 700m 100m 1000m 26m 67m vacuum 6

7 CNGS Target Sealed finned tube Target rod Downstream Window Inert gas Target Support Target (200 cm): 13 graphite rods, 10 cm long, Ø = 5mm and/or 4mm Upstream Window beam σ=0.5 mm 7

8 Hadron Collection Horn and Reflector 6.5 m long 8

9 CNGS Horn and Reflector 9

10 Muon Monitoring 11.25cm Monitoring of: μ intensity μ beam profile shape μ beam profile centre Muon intensity: Up to 7.7x10 7 /cm 2 /10.5 µs 270cm data/simulation comparison (ionization chambers) 10

11 Nominal Beam Parameters 11

12 Oscillations with CNGS ν μ ν μ ν τ ν μ ν e ν e small beam contamination (but almost no ν τ ) L/E P(ν μ ν τ ) cos 4 θ 13 sin 2 2θ 23 sin Δm 2 L E ν <Eν>~17 GeV (ECM >> mτ), L=732 km <L/E>~43 neutrino energy distribution 12

13 Oscillations with CNGS Neutrino beam νμ well adapted for ντ appearance and detection 90% C.L. sin 2 2θ > 0.90, 1.3 < Δm 2 < 3.0x10-3 ev 2 ν μ disappearanc e region θ 23 ~45 maximal mixing? Sensitivity to Δm 2 = x10-3 ev 2 13

14 Neutrino Interactions with nucleous ν ll ν ν ν ll n n n π 0 n Quasi-Elastic Resonant Deep inelastic n hadrons ν ll ll ν ll ν ll W Z n n,h Charged Current (CC) n n,h Neutral Current (NC) interaction cross-section 14

reflector after 4 10 5 pulses (Oct 06) 2007: 6 weeks CNGS run

of ventilation system installed in the CNGS tunnel area due to

15 CNGS Beam 2006: CNGS Commissioning pot Leak in water outlet of cooling circuit of reflector after pulses (Oct 06) 2007: 6 weeks CNGS run pot Maximum intensity: 2x pot/cycle Failure of ventilation system installed in the CNGS tunnel area due to radiation effects in the control electronics 2008: CNGS run: June-November : ~ pot 15

16 Experiments at LNGS 1400 m Gran Sasso ICARUS T600 (CNGS2) ν OPERA (CNGS1) 16

The OPERA Collaboration (Oscillation Project with Emulsion-tRacking Apparatus) (http://operaweb.web.cern.ch/operaweb/index.

17 The OPERA Collaboration (Oscillation Project with Emulsion-tRacking Apparatus) ( Belgium IIHE Brussels Bulgaria Sofia University Croatia IRB Zagreb France LAPP Annecy IPNL Lyon IPHC Strasbourg Germany Hamburg University Münster University Rostock University Israel Technion Haifa S. Korea Italy Bari, LNF Frascati, LNGS, Padova, Salerno Japan Aichi, Kobe, Utsunomiya Russia INR Moscow, JINR Dubna, SINP MSU Switzerland Bern, Turkey Bologna, L Aquila, Napoli, Roma, Toho, Nagoya, ITEP Moscow, NPI Moscow, Obninsk ETH Zurich Jinju METU Ankara 17

18 ν τ detection in OPERA ν μ emulsion grains track segment ν τ τ ~15 grains/50 μm ν τ ν e, ν μ e, μ, h decay kink High spatial resolution is needed (do not forget that large surfaces have to be covered) >25 mrad Nuclear Emulsions Pb ES Pb ES 1 mm (μm) σ θx ~ 2.1 mrad σ x ~ 0.21 μm 18

19 Charged Current Charged Current μ - ν μ Main detection channels μ ν τ ν μ (~ 17%) ν μ ν τ + N X + τ e ν τ ν e (~ 18%) h ν τ n(π 0 ) (~ 50%) cτ ~ 87 μm ( 600 μm of path) τ - ν τ ν hadrons (with 35% of Non-Scaling QE and 65% DIS) (with 11% of Non-Scaling QE and 89% DIS) μ -, e, h no kink, muon from primary vertex Neutral Current ν μ,τ,e hadrons no kink "charm" background ν μ D ν hadrons μ - μ +, e, h kink, wrong sign lepton, muon from primary vertex 19

The OPERA Detector (full description in JINST

) Target Tracker + brick walls (2x31) robot

20 The OPERA Detector (full description in JINST 4, P04018 (2009)) ν "target" wall Pb/emulsion brick wall scintillator strips brick (56 Pb/Em.) Target Tracker + brick walls (2x31) robot muon spectrometer (RPC + drift tubes) 10 X 0 8.3kg 8 cm (10X 0 ) bricks (1.25 kt) 20

The electronic detectors Target Tracker:

Magnetic Spectrometer Dipole magnet + RPC

21 The electronic detectors Target Tracker: plastic scintillator strips, σ~8 mm Magnetic Spectrometer Dipole magnet + RPC (inner tracker) Drift tubes (precision tracker) y x Inner tracker (RPC in magnet, σ~13 mm) coil 12 Fe slabs in total 62 walls (496 modules) 7.5x7.5 m 2 Hamamatsu multianode PMT's (64 channels) Fe (5 cm) RPC B= 1.55 T 8.2 m base slabs Precision tracker Tube: vertical, =38 mm, length=8m σ<0.5 mm 21

BMS (Brick Manipulator System) 5 articulated robots one robot on each

22 Brick production BAM (Brick Assembling Machine) and Target Filling Automatic lead/emulsion piling in a dark room (~700 bricks/day) The BMS (Brick Manipulator System) 5 articulated robots one robot on each side of the detector inserting bricks bricks 1.25 kton Mar 07 Jun 08 22

~ 20 bricks daily extracted thousands of cm 2 /day The European Scanning System The S-UTS

23 Automatic emulsion scanning Based on the tomographic acquisition of emulsion layers. Nominal scanning speed ~20 cm 2 /h. ~ 20 bricks daily extracted thousands of cm 2 /day The European Scanning System The S-UTS (Japan) Customized commercial optics and mechanics (about scanning see Naganawa's presentation) Hard coded algorithms (speed higher than 50 cm 2 /h) 23

24 OPERA: τ search potential Full mixing, 5 years run, 4.5x10 19 pot / year (22.5x10 19 in total) and 1.25 kton Efficiency before τ identification: ε trig. x ε brick x ε geom x ε vertex loc. 99% 80% 94% 90% τ decay channel ε(%) BR% Signal (Δm 2 = 2.5x10-3 ev 2 ) Backgr. τ μ τ e τ h Discovery probability (%) 4-σ evidence 3-σ evidence τ 3h ALL ε x BR =10.6% Δm 2 32 = ev 2 Δm 2 (10-2 ev 2 ) 24

25 The OPERA detector today Super Module 1 Super Module 2 neutrinos 25

26 Event selection using GPS timing information 10.5 μs 10.5 μs 50 ms Extraction length = 10.5 μsec Cosmic ray background 26

27 Neutrino beam seen by OPERA Zenith angle of muon track y θ y >0 θ y <0 z OPERA 2007 August Run result: <θ>=3.4±0.3 MC: simulation from MACRO parametrization, ABSOLUTE normalization 27

28 First event (2007) ν μ μ W hadrons charged current Muon momentum: ~7.5 GeV 28

Event Reconstruction CSd general scan: 50 cm 2 around TT prediction, looking for tracks in all the available angular range (typically ±400 mrad), X ray alignment (10 μm

point, cosmic rays alignment (2 μm accuracy), momentum measurement with Multiple Coulomb Scattering (accuracy: 20%@2 GeV, 40 %@4 GeV), Volume Scan: 1 cm 2, 10 plates (5

29 Event Reconstruction CSd general scan: 50 cm 2 around TT prediction, looking for tracks in all the available angular range (typically ±400 mrad), X ray alignment (10 μm accuracy), tolerances 40 μm, 10 mrad (θ=0), Compton alignment (1μm accuracy), Scan back: alignment with lateral X-ray marks (12 μm accuracy), definition of the stopping point, cosmic rays alignment (2 μm accuracy), momentum measurement with Multiple Coulomb Scattering (accuracy: 20%@2 GeV, 40 %@4 GeV), Volume Scan: 1 cm 2, 10 plates (5 upstream, 5 downstream), offline topology reconstruction. Changeable Sheet Doublet 2 emulsion films downstream to confirm brick predictions from electronic detectors emulsion development 29

30 Charm candidate event 30

31 Charm candidate event 2 electromagnetic showers kink hadron 11 tracks from the primary vertex θ kink = 204 mrad Charged parent flight length ~ 3247 μm Daughter momentum p= GeV/c P t ranges between 600 MeV/c and 1150 MeV/c (90%C.L.) Probability of hadron reinteraction: ~4x10-4 Momenta measured by MCS 31

32 A ν quasi-elastic CC interaction μ 32

33 CNGS Run 2008: 18 June - 03 Nov 2008 integrated pot 1.8E E E E+19 1E+19 8E+18 6E+18 4E+18 2E+18 0 Total: pot Nominal: pot/yr for 5 years SPS timing fault: vacuum leak & magnet exchange PS magnet exchange, septum bakeout MD 18kV cable repair MD CNGS maintenance SPS extraction line: Magnet ground fault Beam to CNGS, LHC, FT, MD CNGS maintenance MD Beam to CNGS, LHC, FT Beam to CNGS, MD 18-Jun 28-Jun 8-Jul 18-Jul 28-Jul 7-Aug 17-Aug 27-Aug 6-Sep 16-Sep 26-Sep 6-Oct 16-Oct 26-Oct 5-Nov 33

34 2008 ν μ CC event ECC level low p track pair opening angle 10 mrad E = 157 MeV 34

2008 Charm candidate event Primary interaction

10-4 % Hadron re-interaction probability :

35 2008 Charm candidate event Primary interaction Decay in 3 prongs muon Three charged prong decay Flight length : ~1150 μm Angle (muon 3 prongs decay) : ~150 Kaon decay probability : 10-4 % Hadron re-interaction probability : 10-5 % muon several charm candidates already observed 35

Vertex location summary for 2008 run 1663 neutrino interactions NC CC Total recorded Bricks received in the labs 208 904 1112 Scanning started 183 836 1019 CS to brick connected 171 789 960 Vertices

36 Vertex location summary for 2008 run 1663 neutrino interactions NC CC Total recorded Bricks received in the labs Scanning started CS to brick connected Vertices located in the brick Passing through Vertices in the dead material June 2009 At least 1 CS track connected in brick: 77% (including brick finding). Located events: 75% Passing through (wall misidentification): 6% Interactions in dead material: ~2% scanning of all 2008 bricks will be finished by September more details on 2008 run in 2009_JINST_4_P

37 2009 run Friday 26/6, pot (506 neutrino interactions already recorded) 37

2009 CNGS performance during last week-end Baseline

lost this year due to the earthquake) ~3.

protons as possible by suppressing the MD and LHC cycles

38 2009 CNGS performance during last week-end Baseline expectation: 153 days of run (available for CNGS, 2 weeks lost this year due to the earthquake) ~ pot in total Agreement to provide CNGS as much protons as possible by suppressing the MD and LHC cycles during nights, week-ends and whenever possible. nominal CNGS intensity: pot/year 38

39 ICARUS LNGS: status Italy: LNF, LNGS, L Aquila, Milano, Napoli, Padova, Pavia, Pisa Poland: Katowice, Krakow, Warsaw, Wroclaw USA:UCLA Switzerland: CERN About 90 physicists ICARUS LNGS (16/06/2009) ICARUS T600 plant inside LNGS Hall B 39

ICARUS (T600) Two identical modules 3.6 x 3.9 x 19.6 275 m3 each Liquid Ar fiducial mass: 476 t Drift length = 1.5 m HV = -75 kv, E= 0.

40 ICARUS (T600) Two identical modules 3.6 x 3.9 x m3 each Liquid Ar fiducial mass: 476 t Drift length = 1.5 m HV = -75 kv, E= 0.5 kv/cm 4 wire chambers: 2 chambers / module 3 readout planes / chamber: at 0,+60, wires PMT for scintillation light: (20+54) PMTs, 8 VUV sensitive, λ=128 nm 40

41 Collaboration progresses during last year Leak search and feedtrough repair/substitution Electronics racks cabled to all wire signal feedtroughs; tests completed Vacuum systems (valves, pumps, circuits) mounted and tested Slow Control system for pressure, temperature, wall displacement and LAr level monitor completed and tested Software development for event visualization and track reconstruction 41

42 Fluids Skids, pumps and lines Top plant On April 2009 tests on the new system concluded: liquefier is reliable and stable Cryogenic plant assembly (Air Liquide) LAr purification systems LN2 pumps Cryogenic plant is completed and working properly (for more details see A. Menegolli's talk) LN2 circuits 42

43 Collaboration is ready for the commissioning of the detector, vacuum phase to be started in middle of July - ICARUS detector (external connections) completion OK! - Major leak search and repairing via pressure tests OK! - Tests of read out and electronics - AIR LIQUIDE overall plant completion - LNGS infrastructures completion & commissioning - STIRLING Commissioning OK! OK! OK! OK! - Vacuum pumping and leak search (Helium test) July 09 - Delivery of LAr from Air Liquide Sept 09 - T600 filling start-up Sept 09 Hopefully, this would allow to observe the first CNGS neutrinos before the end of the current run. 43

44 Conclusions CNGS runs in stable conditions Protons on the Target less than nominal value (< /year) First full year of data taking 2008: pot 1700 neutrino interactions recorded by OPERA Not yet ν τ candidates in OPERA "charm" events already observed About pot expected this year (data taking already started the 1 st of June, only 2 weeks delay due to the earthquake) ICARUS-T600 expected to observe the first CNGS neutrinos before the end of the year. 44

A. Chukanov On behalf of OPERA collaboration JINR, Dubna TAUP 2011, Munich, 5-9 september, 2011

A. Chukanov On behalf of OPERA collaboration JINR, Dubna TAUP 2011, Munich, 5-9 september, 2011 Outline OPERA experiment Event location procedure n t candidate Background estimation Conclusion 2 OPERA: