Presentation is loading. Please wait.

Presentation is loading. Please wait.

LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 1 OPERA status.

Similar presentations


Presentation on theme: "LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 1 OPERA status."— Presentation transcript:

1 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 1 OPERA status

2 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 2 uOPERA experiment: from detector construction to a working apparatus n Practical running update uPast neutrino runs n Detector target filling n 2006-2007-2008 uData collection and analysis n Statistics n Prospects uAfter April 6 L’Aquila seism OPERA French groups Annecy LAPP: D. Duchesneau, J. Favier, H. Pessard, A. Zghiche Lyon IPNL: D. Autiero, T. Brugière, A. Cazes, L. Chaussard, Y. Déclais, J. Marteau, E. Pennacchio, T. Tran Strasbourg IPHC: M. Dracos, C. Jollet, A. Meregaglia Outline:

3 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 3 OPERA: Direct observation of ν τ appearance CERN LNGS 730 km OPERA Long baseline experiment in Europe Nuclear emulsion techniques OPERA CNGS : 17 GeV  beam from CERN to Gran Sasso From SPS: 400 GeV/c Cycle length: 6 s Extractions: –2 separated by 50 ms Pulse length: 10.5  s Beam intensity: –2.4 10 13 proton/extr. Expected performance: –4.5  10 19 pot/year  SK (1998): atmospheric neutrino anomaly interpretable as    oscillation  CHOOZ: no  → e oscillation  SK  disappearance oscillation signal confirmed by K2K and MINOS Gran Sasso underground laboratories: 1400 m rock overburden

4 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 4 Experimental signature: tau neutrino CC detection  CC interaction      + N   + X oscillation      B. R. ~ 17% h   n(  o )B. R. ~ 50% e    B. R. ~ 18%        n(  o ) B. R. ~ 14%    -- Decay “kink”  -- cc  oscillation -- c  ~ 87  m no-oscillation (≈ 600  m of path) (with ≈ 35% of Non-Scaling QE and 65% DIS) (with ≈ 11% of Non-Scaling QE and 89% DIS)

5 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 5 Pb Emulsion layers  1 mm ECC concept (Emulsion Cloud Chamber): 1 mm thick Pb layers interleaved with emulsions films (2 emulsion layers  m thick poured on a 205  m plastic base ) emulsion support 12.5cm 10.2cm Track reconstruction accuracy in emulsion:  x  1 µ m   1 mrad One “BRICK” : - 57 emulsion films - 56 Pb plates - a box with a removable pair of films CS 10 X 0 Changeable Sheet Doublet (CSd) 8, 6 Kg To reach O(Kton) mass, the OPERA lead–emulsion high granularity target is segmented into modular units called bricks The OPERA way to detect the tau kink 150 000 bricks ~1.25 Ktons

6 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 6 20 m 10 m Super Module 1 Super Module 2 electronics racks Muon Spectrometer Target TARGET TRACKERS 2 x 31 scintillator strips walls 256+256 X-Y strips/wall WLS fiber readout 64-channel H7546 PMT 63488 channels 0.8 cm resol. ε ≅ 99% rate ≅ 20 Hz/pixel @1 p.e. INNER TRACKERS 990-ton Fe dipole magnets (B= 1.55 T) instrumented with 22 RPC planes (streamer mode) 3050 m 2,  ~1.3 cm spatial resol. ε ≅ 96% (geometrical) HIGH PRECISION TRACKERS 6 drift-tube layers/spectrometer spatial resolution < 0.5 mm Veto Drift tubes RPC ECCs scint. strips BRICK WALLS 53 walls filled with bricks 2850 bricks/wall BMS Brick Manipulator system The detector Detector construction: Sept. 2003 - spring 2007 Target Trackers neutrino trigger brick localization RPC + drift tubes in spectrometers: muon ID, momentum, charge

7 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 7 uCNGS-LNGS synchronization based on GPS. Present precision 100 ns (could be improved up to 10 ns) uDAQ live-time >99%. Live-time during CNGS 98.9% uDirection and momentum reconstruction for CNGS event uCharge and momentum reconstruction for cosmics OK (Negligible cosmics bg.) OK In progress OPERA performance as on-line detector

8 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 8 @ CERN @ Gran Sasso 2000 20042006 20081998 2002 2010 Approval End of civil engineering End of construction Commissioning Elect-det only 60000 bricks 150000 bricks OPERA CNGS CNGS runs u2006: short pilot run No bricks. Stop due to horn cooling. u2007 (24 th September – 20 th October): 0.082 x 10 19 pot. Only ~3.6 nominal days: radiation shielding problems. 38 interactions in the bricks (32±6 expected) u2008 (June 18th-November 3rd): 1.782 x 10 19 pot 10100 events on time ~1700 interactions in bricks 0.7  events expected 2008 first time long physics run, poor CNGS performance at beginning, better at the end (more CNGS cycles)

9 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 9 CNGS Run 2008: 18 June- 03 Nov 2008 Total: 1.78·10 19 pot 18kV cable repair MD PS magnet exchange, septum bakeout MD SPS timing fault: vacuum leak & magnet exchange CNGS maintenance SPS extraction line: Magnet ground fault MD CNGS maintenance Nominal: 4.5 10 19 pot/yr Beam to CNGS, LHC, FT, MD Beam to CNGS, LHC, FT Beam to CNGS, MD

10 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 10 After the LHC accident, further increase of the intensity for OPERA (duty cycle 37.5%  83%). SFTPRO3xCNGSLHC MD 4 x CNGS2xCNGS MTE/ CNGS LHC

11 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 11 uTrigger + event selection “on time” with CNGS uBrick finding reconstruction algorithm applied to electronic data to select the best candidate brick to contain the neutrino interaction vertex uBrick removed by the Brick Manipulation System (BMS) and exposed to (frontal) X-rays to make an alignment reference between CSd and brick uCSd detached from brick, films developed and analysed in one of the CS Scanning Stations, in Europe (LNGS) or in Japan (Nagoya) uIf a TT-predicted track is found in the CSd, the brick is exposed to (lateral) X-rays beam and to cosmic rays for sheets alignment. Brick is disassembled and emulsion films developed and sent to one of the scanning labs uTracks found in the CSd are searched for in the most downstream film of the brick and followed (scan-back procedure) uA volume scan around the neutrino interaction point is performed and the neutrino vertex is located OPERA data taking flow Several ancillary facilities have been validated at nominal speed only in 2008 Brick assembly, manipulation, DB tracing, emulsion development and assoc. logistics were big engineering enterprises…

12 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 12 uPrediction of the brick where interaction occurred uExtraction of Bricks at the rate of CNGS events uAlignment and development of Changeable Sheets uScanning of the Changeable Sheets uIdentification of the primary vertex uKinematic reconstruction and decay search Part. validated (*) Fully validated In progress (**) (*) Extr. of 1° brick nearly completed. 2° in progress. (**) First results on a subsample of ~200 events OPERA performance as hybrid detector

13 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 13 Preliminary Check sample of extracted 1° bricks with CS scanned: 700 events (full stat. results will follow) Tracks found in the CS: 60% 1 st Brick finding (correct for dead material and CS efficiency): 70% (OK!) Expectation after 2 nd extraction: 80% (check with real data in progress) Manca plot Brick finding Brick extractions End of CNGS run Up to 25 bricks per shift

14 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 14 MC independent test of track finding efficiency in CS in a subsample of fully located event (  sb ~ 90%) OK! BrickCSd LNGS (Italy) NAGOYA (Japan) LNGS Scanning of Changeable Sheets

15 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 15 ‘data collection’ from emulsions In progress: vertex efficiency with large statistics Backscattering studies charm topologies search Vertex finding and decay search Test sample ~200 fully rec. events seems OK, full results need some more months.  12 57 565554 53 5251504948 … 2 1 CSd CSd general scan: 50 cm 2 around TT prediction angular range ±400 mrad alignment by Xray 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

16 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 16 NCCCTotal Bricks scanned162693855 CS to brick connected151666817 Vertices located in the brick100530630 Passing through103545 Vertices in the dead material2911 PRELIMINARY Analysis April 3 rd 2009 Vertex location summary, 2008 run At least 1 CS track connected in brick: 96% Located events: 77% Passing through (wall misidentification): 6% Interactions in dead material: ~ 2%

17 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 17 17 pair opening angle 10 mrad E  = 157 MeV low p track A beautiful   CC ECC level

18 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 18 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 Charm search 8 candidates found for 10 expected in a sample of ~550  CC

19 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 19 kink angle = 0.204 rad Decay length = 3247 μm p(daughter) = 3.9 +1.7 -0.9 GeV p t = 796 MeV p t MIN = 606 MeV (90% CL) The charm decay kink Secondary Vertex (1 prong decay) ‏

20 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 20 uA strong earthquake (M I =6.3) hit the L’Aquila area on April 6 th at 03:32 am. u295 died, 1170 were hurt at L’Aquila and surrounding villages uThe quake epicenter was only at 8.8 km depth, causing strong damages in a limited area. Many houses collapsed, 10 to 15000 buildings were damaged. 50K people are homeless. u38K people still lived in tents last week, either homeless of fearing aftershocks (that lasted more than 2 weeks). uLNGS laboratories, ~20 km away, have no apparent damages. OPERA seems intact, although geometric measurements should be done to check its structure and alignment. uThe most important problem for the lab is the situation of the staff. LNGS will officially reopen on May 5 th. uThose dramatic circumstances will translate into some delay, all activities being stopped for 1.5 months: brick extractions and (re)insertions, CS scanning -> 2008 brick analysis are affected. Consequences of the April 2009 L’Aquila seism

21 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 21 Detector target filling situation Mar 07 July 08 146405 bricks were produced and installed in the detector until July 2008 Target preparations for 2009 -3200 new bricks, produced after the recovery of the lead production chain (damaged by an explosion in 2008) were loaded to complete the OPERA target. Remain to be inserted: 2500 bricks -In preparation of the 2009 run, from February to April, the OPERA target was under a reshuffling operation needed to replace CS films in about 15000 bricks (10% of the whole target). About 8200 remain to be re-inserted. -About 300 candidate bricks from 2008 run remain to be extracted (2 nd brick extraction).

22 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 22 uIn 2008, after a difficult startup, OPERA got from CNGS a significant integrated intensity (~2. 10 19 p.o.t.). 2008 was OPERA first real physics run. uThe construction of OPERA is complete; all sub-detectors and ancillary facilities are fully operative. u4 months after the end of the data taking, most of the analysis chain has been validated. uThe last steps, vertex and kinematic analysis of the full sample, will be completed in a few months. uFollowing the L’Aquila earthquake in April, CERN is awaiting a green light of OPERA to start the 2009 CNGS operation, hopefully with very little delay. uOPERA needs as many pots as possible soon to succeed in its physics program. Conclusions

23 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 23 The End

24 LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 24 Expected background:  Charmed particles produced in  CC and NC interaction uHadron 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. 0.172.9  -  µ - 0.173.5 -  e- -  e- 0.243.1  -  h - 0.170.9  -  3h Background: Signal  m 2 = 2.5 x 10 -3 eV 2  - decay channels 0.75 ALL10.4  (%) BR  (%)          x BR =10.6% Physics potential


Download ppt "LPNHE Paris, April 28 th, 2009GDR NeutrinoH. Pessard / 1 OPERA status."

Similar presentations


Ads by Google