HEP Conference 2009, Krakow, PolandH. Pessard / 1 Henri Pessard / LAPP Annecy (on behalf of the OPERA Collaboration) Status of the OPERA neutrino experiment

HEP Conference 2009, Krakow, PolandH. Pessard / 2 The Opera Collaboration 34 INSTITUTIONS, ~200 PHYSICISTS LAPP Annecy IPNL Lyon IPHC Strasbourg INR, LPI, ITEP, SINP Moscow JINR Dubna INPE Obninsk IRB Zagreb Bari Bologna L’Aquila LNF Frascati LNGS Napoli Padova Roma Salerno Bern ETH Zurich ULB Brussels Hamburg Münster Rostock Sofia Aichi Toho Kobe Nagoya Utsunomiya Technion HaifaMETU Ankara Jinju

HEP Conference 2009, Krakow, PolandH. Pessard / 3 OPERA Neutrino long baseline in Europe CNGS: oscillation in appearance mode CNGS : High energy  beam from CERN to Gran Sasso Gran Sasso underground laboratories: 1400 m rock overburden CERN LNGS 730 km OPERA SK (1998) : atmospheric neutrino anomaly interpretable as    oscillation CHOOZ : no (or very small)  → e oscillation SK  disappearance oscillation signal confirmed by K2K and MINOS 730 kmL 4%  /  negligible   prompt 17 GeV 0.87%( e + e )/  Direct observation of  events Nuclear emulsions in hybrid detector

HEP Conference 2009, Krakow, PolandH. Pessard / 4 CERN-Neutrino-to-Gran-Sasso Protons from SPS: 400 GeV/c Cycle length: 6 s Extractions: –2 separated by 50 ms Pulse length: 10.5  s Beam intensity: – proton/extr. Expected performance: –4.5  pot/year 17 GeV  beam optimized for  detection Vacuum 700m 100m1000m67m26m For 5 years at nominal intensity, 200 days/y and 1.3 kton target: ~  CC+NC ~ 170 e +  e CC x Nb of  CC  m 2 (eV 2 )

HEP Conference 2009, Krakow, PolandH. Pessard / 5 OPERA principle: tau detection  CC interaction     + N   + X oscillation      B. R. ~ 17% h   n(  o )B. R. ~ 49% e   e B. R. ~ 18%        n(  o )B. R. ~ 15%   Decay “kink”  -- -- [c  ~ 87  m]  --  no-oscillation (35% of Non-Scaling QE and 65% DIS) (11% of Non-Scaling QE and 89% DIS) Pb Emulsion layers  1 mm Micron precision + target mass using the ECC (Emulsion Cloud Chamber) concept: Thin metal plates interleaved with nuclear photographic emulsions on films. Successful application in DONUT, discovery of  (2000) 3D tracking: 32 grains/100 

HEP Conference 2009, Krakow, PolandH. Pessard / 6 OPERA ECC: 1 mm lead plates and industrially produced emulsion films (2 emulsion layers of  m on a 205  m plastic base ) 12.5cm 10.2cm Track reconstruction accuracy in emulsions:  x  1 µ m   1 mrad One “BRICK” : - 57 emulsion films - 56 Pb plates - a box with a removable pair of films called Changeable Sheets To keep the precision within a O(Kton) mass, the OPERA lead/emulsion target is segmented into modular units called BRICKS The OPERA way to the tau: the ‘brick’ bricks ~1.25 Ktons CS box 10 X 0 8,3 Kg Spider structureChangeable Sheet Doublet (CSd) in its envelope The “BRICK” can provide: - neutrino vertex reconstruction - search for decay topologies - meas. of charged p. momenta by MCS - dE/dx for  separation at track end - electron ID and energy measurement

HEP Conference 2009, Krakow, PolandH. Pessard / 7 20 m 10 m Super Module 1 Super Module 2 Muon Spectrometer Target TARGET TRACKERS 2x31 scintill. strips walls X-Y strips/wall WLS fiber readout 64-channel PMTs channels 0.8 cm resol.,  99% rate 20 p.e. INNER TRACKERS 990-ton dipole magnets (B= 1.55 T) instrumented with 22 RPC planes 3050 m 2, ~1.3 cm res. HIGH PRECISION TRACKERS 6 drift-tube layers/spectrometer spatial resolution < 0.5 mm Veto Drift tubes RPC ECCs scint. strips BRICK WALLS 2850 bricks/wall 53 walls BMS Brick Manipulator system O scillation P roject with E mulsion t R acking A pparatus Detector supermodules construction: Sept spring 2007 Target Trackers neutrino trigger brick localization RPC + drift tubes in spectrometers: muon ID, momentum, charge 10 m

HEP Conference 2009, Krakow, PolandH. Pessard / 8 Mar 07 Jun bricks produced and installed in the detector A heavy enterprise: Brick Assembly Machine 5 piling robots, ~700 bricks/day Brick Manipulator System One robot on each side

HEP Conference 2009, Krakow, PolandH. Pessard / 9 Trigger + event selection “on time” with CNGS Brick finding reconstruction algorithm applied to electronic data to select the best candidate brick to contain the neutrino interaction vertex Brick removed by the Brick Manipulation System (BMS) and exposed to frontal X-rays to make an alignment reference between CSd and brick CSd detached from brick, films developed and analysed in one of the CS Scanning Stations, in Europe (LNGS) or Japan (Nagoya) If a TT-predicted track is found in the CSd, the brick is exposed to lateral X-rays beam and to high E. cosmic rays for sheets alignment. Brick is disassembled and emulsion films developed and sent to one of the scanning labs Tracks found in the CSd are searched for in the most downstream film of the brick and followed (scan-back procedure) A volume scan around the neutrino interaction point is performed and the neutrino vertex is located and studied OPERA data taking flow Several ancillary facilities have been validated at nominal speed in 2008 Brick assembly, manipulation, DB tracing, emulsion development and associated logistics have been big engineering enterprises…

HEP Conference 2009, Krakow, PolandH. Pessard / 10 OPERA bricks measurement CS and bricks are shared among emulsion scanning labs: Europe Japan High speed CCD camera (3 kHz) Hard-coded algorithms and custom mechanics Piezo-controlled objective lens ESS microscope S-UTS microscope Brick emulsion scanning: 2 labs Nagoya is CS scanning center CMOS camera Automated emulsion scanning Commercial hardware Software algorithms Scanning speed up to 75 cm 2 /h Scanning speed 20 cm 2 /h Brick emulsion scanning: 8 labs in Italy, 1 lab. in Switzerland LNGS is CS scanning center

HEP Conference 2009, Krakow, PolandH. Pessard / Gran Sasso Approval End of civil engineering End of construction Commissioning Elect-det only bricks bricks OPERA CNGS CNGS beam CNGS runs u2006: short pilot run Early stop due to horn problems u2007 (24 th September – 20 th October) 0.08 x pot. Only ~3.6 nominal days. Stop due to radiation shielding problems. 38 interactions in the bricks u2008 (June 18 th - November 3 rd ) x pot ~1700 events in the bricks 0.7  events expected) u2009 (June 1 st - on going) Better start, present extrapolation 3.2 x pot. More is needed. Request is 4.5 x pot 2008 first long physics run, although with poor performance of CNGS in the first 3 months

HEP Conference 2009, Krakow, PolandH. Pessard / 12 A strong earthquake (M I =6.2) hit L’Aquila on April 6 th. The epicenter was 15 km away from the Gran Sasso laboratory. 306 killed, 1600 injured at L’Aquila and surrounding villages. Many houses collapsed, buildings were damaged. The epicenter being only 8.8 km deep, damages are in a limited area. Effects were further damped in the caverns. Starting the 2009 run and the L’Aquila seism Peak accelerations: Underground lab g External lab g L’Aquila up to 0.64 g Only minor effects in LNGS laboratories. OPERA found basically intact, geometric measurements showed no significant alignment changes. Major logistic difficulties for the local personnel. Difficult restart of activities after the LNGS closure up to May 5 th. Big OPERA effort to let CNGS start with only 2 weeks delay !

HEP Conference 2009, Krakow, PolandH. Pessard / 13 L’Aquila seism consequences -Small tail of 3200 bricks produced in 2009 to insert -Finish reinsertion of bricks (CS packed in vacuum replacement) -Reorganize target in a compact way Tasks finished in June Those dramatic circumstances caused delays in the following Gran Sasso activities, stopped for ~1.5 months. End of 2008 brick processing: Underground, brick extractions from detector, CS marking, CS development, brick marking In external lab, CS scanning, brick cosmic exposure, brick emulsions development BMS activities to prepare 2009 run: Work stations points Free corridor passage Drum Loading/ unloading point Storage pallets point

HEP Conference 2009, Krakow, PolandH. Pessard / 14 Debris in one magnet moved near a sensitive area and gave rise to a weak ground leakage current (now cured) Changes observed on-line(!) in the light tightness of some TT scintillator strips (DAQ did not stop working) Shaking a multi-kiloton detector… Walls hosting the bricks, hold by springs, experienced a jitter of about 1cm No other consequences of the seism were observed, thanks to the anti-seismic studies made for OPERA

HEP Conference 2009, Krakow, PolandH. Pessard / E 19 pot Beam loss, vacuum accident 27/6-2/7 Unix Time pot Wed 18/6/08 17:00 Start at low intensity 10/7-18/7 Earth fault on PS magnet Long MD stop + MTE kicker problem 7/7 6:00 – 10/7 12:00 Stop 3/11/08 8:00 18KV cable accident 25/7 PS septum + Long MD 8-14/8 Horn + PS vacuum Week 1/9 CNGS quadrupole 14-17/9 6-8/10 MD Horns filters 19-20/10 CNGS run 2008, prospects for pot 2008 pot

HEP Conference 2009, Krakow, PolandH. Pessard / 16 Pot collected in 2009 up to Monday 13/ Unix time Saturday 30/5/09 Run start 1/6 CNGS access on 3/6 (PLC temperature probes) pot 8.05 E 18 pot PS vacuum leak 10/6 00:00 11/6 1:07 MD Monday 15/6 8:00 Friday 19/6 8:00 MD + Septum water leak Tuesday 30/6 8:00 Friday 3/7 7:15 Events on-time : 4950 On-time in target : 874 time pot per second Super-cycle length as of July 14 th SFTPRO 3xCNGS LHC MD SPS super cycle with 3 CNGS cycles time After LHC accident in %  83% 4 x CNGS 2xCNGS MTE/ CNGS LHC

HEP Conference 2009, Krakow, PolandH. Pessard / 17 uCERN-LNGS synchronization based on GPS. Precision 100 ns uFor 2008 run, on time events, 1663 in target uDAQ livetime ~ 99%. uDirection and momentum reconstruction for CNGS events OK uCosmics charge and momentum reconstruction OPERA as a real-time detector Negligible cosmic background First ICRC conf. Lotz, July 09 R. Acquafredda et al., New J. Phys. 8 (2006) 303 Mis-id. proba Muon deflection Exp. data MC data Atmospheric muon charge ratio

HEP Conference 2009, Krakow, PolandH. Pessard / 18 ~OK OK In progress (*) In progress (**) (*) 2 nd bricks in progress, vertex done for ~70% of events. (**) decay search done for ~50%, work on going OPERA performance as hybrid detector uPrediction of the brick where interaction occurred uExtraction of 1 st Brick at CNGS events rate uAlignment + development for CSd of 1 st brick uScanning of CSd 1 st brick uIf validation, development of 1 st brick uIf not, processing of 2 nd brick uSearch for the primary vertex uDecay search and kinematic reconstruction OK In progress (*) 2008 data

HEP Conference 2009, Krakow, PolandH. Pessard / 19 Check 2008 sample of extracted 1 st bricks with CS scanned: Tracks found in the CS: 65% 1 st Brick finding (corrected for dead material and CS efficiency): 72% as expected (OK!) Expectation after 2 nd extraction: > 80% Checks on 2 nd bricks in progress Work on going on tracking + algorithms Manca plot Brick finding Brick extraction and processing Up to 25 bricks per shift End of CNGS run Restart

HEP Conference 2009, Krakow, PolandH. Pessard / 20 Experimental test of track finding efficiency in CS in a subsample of fully located event (  CS ~ 90%) OK! Brick CSd LNGS: 7  10 microscopes, 200 cm 2 /h Scanning of Changeable Sheets Nagoya: 5 S-UTS. 220 cm 2 /h Earthquake Speed reached 20 CS/day Projected CS/day

HEP Conference 2009, Krakow, PolandH. Pessard / 21 ‘data collection’ from emulsions In progress: vertex efficiency with large statistics Backscattering studies charm topologies searches Vertex finding and decay search Test sample ~200 fully rec. events seems OK, first results:  … 2 1 CSd CSd general scan: 50 cm 2 around TT prediction angular range ±400 mrad alignment by X-ray marks (10  m accuracy) Scan back: alignment using cosmic ray tracks (2  m accuracy) stopping point Volume Scan: 1 cm 2, 10 plates  track IP Multiplicity N. Agafonova et al., 2009_JINST_4_P06020

HEP Conference 2009, Krakow, PolandH. Pessard / 22 as of July 14 th Vertex location summary, 2008 run At least 1 CS track connected in brick: 94% Located events: 77% Passing through (int. in upstream wall): 5% Interactions in dead material: ~ 2% NCCCTotal Bricks received in labs Scanning started CS to brick connected Vertices located in the brick Interaction in upstream wall Vertices in dead material41721

HEP Conference 2009, Krakow, PolandH. Pessard / pair opening angle 10 mrad E  = 157 MeV low p track A beautiful  CC ECC level

HEP Conference 2009, Krakow, PolandH. Pessard / 24 A charm candidate Kink PRELIMINARY e.m. showers vertex signature already evident in the CS  The charmed hadron is “inside” the hadronic jet and back to back with the muon Decay searches Several charm candidate events have been detected. Validations are on going.

HEP Conference 2009, Krakow, PolandH. Pessard / 25 kink angle = rad Decay length = 3247  m p(daughter) = GeV p t = 796 MeV p t MIN = 606 MeV (90% CL) (probability ~ for an hadron re-interaction) The charm decay kink Secondary Vertex (1 prong decay) ‏

HEP Conference 2009, Krakow, PolandH. Pessard / 26 Decay search is in progress and special events (e.g. charm candidates in the C1, C3, V2, V4 topologies) have already been found. Still important improvements were achieved in the last few months: Track (basetrack) loss can be recovered if we can use the “microtracks” level After microtrack “basetrack” Decay search progress Before

HEP Conference 2009, Krakow, PolandH. Pessard / 27 Recovering a neutral charm decay

HEP Conference 2009, Krakow, PolandH. Pessard / 28 uThe OPERA detector is complete since one year. All sub-detectors and ancillary facilities are operative at full nominal speed. Including the continuous data extraction from emulsions, OPERA has achieved a major engineering enterprise. uMost of the analysis chain is now validated. Last steps in vertex and kinematic analysis will be completed in a few months for the 2008 sample. Reevaluation of efficiencies and background is in progress using real data. uThe L’Aquila earthquake of April 6 th caused no damage to Gran Sasso equipments. Perturbations in the laboratory functioning have however induced delays in the local analysis operations. uThe 2009 CNGS run preparation was affected but the effect could be reduced to a couple of weeks. The run started successfully on June 1 st.  We hope to get soon the first  decay candidates. A couple will be expected in the sample. uTo reach quickly its physics goal, OPERA relies on the CERN support to have soon the CNGS running at nominal intensity. Conclusions

HEP Conference 2009, Krakow, PolandH. Pessard / 29 The End

HEP Conference 2009, Krakow, PolandH. Pessard / 30 Expected background: - Charmed particles produced in  CC and NC interaction - Hadron re-interactions in lead - Large angle scattering of muons produced in  CC events -  0 misidentification Full mixing, 5 years run, 4.5x10 19 pot / year and target mass = 1.3 kton Occurs if primary muon is not detected and possible wrong charge measurement of secondary muon. Muon ID is a crucial issue  -  µ -  e- -  e  -  h  -  3h Background: Tau events observed  m 2 = 2.5 x eV 2  - decay channels 0.75 ALL10.4  (%) BR (%)          x BR =10.6% Physics potential Discovery probability (%)  m 2 (eV 2 ) 4-  evidence 3-  evidence MINOS 2008

HEP Conference 2009, Krakow, PolandH. Pessard / 31 ▪ Proposal in 2001 ▪ First successful test of MTE in August 2008 Improving CNGS intensity: the multi-turn extraction

HEP Conference 2009, Krakow, PolandH. Pessard / 32 Unix time Pot/extraction 2 E 13 pot/extraction Extraction 1 Extraction 2 CNGS Intensities per extraction in 2009