OPERA : CERN-LNGS Long Base ?

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OPERA CERN-LNGS Long Base ?µ??t Appearance
Experiment
Belgium IIHE(ULB-VUB) Brussels
COLLABORATION
Bulgaria Sofia University
China IHEP Beijing, Shandong
Croatia Zagreb University
France LAPP Annecy, IPNL Lyon, LAL Orsay, IRES
Strasbourg
Germany Berlin, Hagen, Hamburg, Münster, Rostock
Israel Technion Haifa
Italy Bari, Bologna, LNF Frascati, LAquila,
LNGS, Naples, Padova, Rome, Salerno
Japan Aichi, Toho, Kobe, Nagoya, Utsunomiya
Russia INR Moscow, ITEP Moscow, JINR Dubna,
Obninsk
Switzerland Bern, Neuchâtel
Turkey METU Ankara
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OPERA CERN-LNGS Long Base ?µ??t Appearance
Experiment

• Motivations
• Direct observation of ?µ -gt ?t oscillation by
  detection of ?t Pb CC interaction in initially
  pure ?µ beam (0.8 ?e, 2 ?µ)
• ?µ -gt ?e observation ?13 measurement

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OPERA CERN-LNGS Neutrino Beam (CNGS)
4.5x1019 pot / year ltEgt 17 GeV
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Experimental technique

• Emulsion Cloud Chamber (ECC)
• Emulsions for tracking, passive material as
  target
• Basic technique established
• charmed X-particle first observed in cosmic
  rays (1971)
• DONUT/FNAL beam-dump experiment nt events
  observed
• Dm2 (1.3 - 3) x 10-3 eV2 ? Mtarget 2
  kton
• large detector ? sensitivity, complexity
• modular structure (bricks) basic performance
  is preserved

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OPERA Detector Supermodule structure
Pb/Em. ECC brick
Basic cell
Pb/Em. target
1 mm
Emulsion
Pb
Emulsion analysis ? vertex ? decay kink ?
e/?/µ/p ID, multiple scattering, kinematics
Extract selected brick  

• Electronic detectors target tracker, µ
  spectrometer, veto counters
• find the brick with n interaction
• m ID, charge p

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OPERA Detector Disposition in LNGS underground
lab
Underground assembly space (2003 - 2006)
BAM
Borexino
Hall B
Hall C
Emulsion storage
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OPERA Detector Disposition in LNGS underground
lab
31 target planes / spectrometer (206336 bricks,
1766 tons)
Rear damping structure
Front damping structure
? ?
Mechanical structure and risk analysis
study accepted by safety authorities
Electronic barrack
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ECC Brick
10X0 ( 57 emulsion films )
Packing Options Vacuum Mechanical
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Day by day experiment operation scheme

• Emulsion Scanning stations
• locate n interaction
• ? detection

• Gran Sasso
• tag n interaction
• extract ECC brick

ECC brick

• 30bricks/day
• cosmic ray exposure
• develop emulsion sheet etc.

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OPERA Event rate
5 years running _at_ 4.5 1019 /year in shared mode
OPERA 1.766 ktons
?µCC 24300
?µNC 7300
?µCC 510
?eCC 194
?eCC 17
?tCC interactions
?m2 OPERA
1 x 10-3 eV2 24
2 x 10-3 eV2 95
3 x 10-3 eV2 214
__
__
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Number of events full mixing, 5 years run _at_
4.5(6.76)x1019 pot / year
signal (Dm2 1.3 x 10-3 eV2) signal (Dm2 2.0 x 10-3 eV2) signal (Dm2 3.0 x 10-3 eV2) BKGD
Final Design 3.1(4.7) 7.3(11) 16.4(24.6) 0.7(1.06)
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CNGS schedule
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OPERA construction tasks and schedule

• Spectrometer Magnet, RPC, XPC and Precision
  Tracker
• Veto and Beam monitoring
• Target Brick wall and Target Tracker
• DAQ
• Brick production and Handling
• Scanning and Computing

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OPERA construction tasks and schedule
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Spectrometer construction
Tests at Frascati lab
coil
Total Fe weight 1 kton
B 1.55 T
slabs
base
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Spectrometer construction Aug 2003
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Spectrometer construction Dec 2003
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Precision tracker

• Electronics
• FE board ready
• TDC chip tested, board being designed
• DAQ running
• HV board final design in progress

Full size prototype as seen from the top

• Performance
• efficiency 99.1
• resolution ? 300 µm

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Target tracker
7m

• XY planes, 7000m2 in total
• 32256 Scintillator strips 7m x 2.5cm x1cm
• AMCRYS-H (Kharkov) Kuraray WLS
• 1000 MaPMT Hamamatsu 64channels
• Dedicated Front End electronics for
• gain correction
• Autotriggerable and threshold _at_ 1/5 p.e

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Target tracker first wall constructed (Strasbourg)
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Target tracker delivery

• Produce about 8 modules/week.
• Delivery at GS (modules already calibrated)
• 16 modules February 2004
• 56 modules May 2004
• 56 modules July 2004
• 56 modules September 2004
• 56 modules November 2004
• 56 modules January 2005
• 56 modules March 2005
• 56 modules May 2005
• 56 modules July 2005
• 40 modules September 2005
• TT installation 31/03/2004 to 18/01/2006

TT Walls will be mounted outside (about 15 walls
prepared in advance) and slided inside the
detector after each brick wall installation.
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The 3 ingredients of the DAQ architecture
Same architecture for target tracker, RPC and
Precision tracker
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ECC components emulsion lead
Mass production starts April 2003 (150 000
m2) Refreshing done in the Tono Mine in Japan 2
years duration One batch sent to LNGS every 2
months starting august 2003 ?
emulsion storage ready _at_ LNGS (Hall B) june 2003
100mm
125mm
Lead from Boliden
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Brick Manipulator prototype (LAPP Annecy)
Naples-Frascati wall
CCD Camera
The Vacuum sucker Vehicle (VV)
VV cable loop driving system
VV cable
50 bricks/day 3 hours
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Emulsion scanning
European prototype
sq 2mrad sx 0.5mm
Dedicated hardware Hard coded algorithms
Commercial products Software algorithms
Routine ? 5cm2/hr Near future ? 20cm2/hr
S-UTS prototype at Nagoya
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Emulsion scanning ?t?t-?m- simulated
reconstructed event
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Important milestones

• november 2003 started SM1 Magnet RPC
  installation
• June 2004 starts SM1 Target installation
• January 2005 BAM and BMS installation
• July 2005 starts filling bricks

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Conclusions

• Detector construction and installation
• Mass production started
• Large and complex detector installation started
• Detector (and CNGS beam !) will be ready in 2006

• Important Physics Program
• First evidence of nm-nt appearance in few years
  data taking
• In a five years run 7(11) signal (_at_2.0 x 10-3
  eV2) and 0.7(1.) background events
• Studies to improve efficiency and to reduce the
  background
• Multi prong t decay channel under study
• Measurement of q13 ( See talk by P.Migliozzi )

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OPERA Sensitivity
5 years data taking
?m2 1.2x10-3 eV2
at full mixing sin2 (2?) 6.0x10-3
at large ?m2
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Brick Assembling Machine (BAM) schedule

• Final specifications December 2002
•  
• End of market search March 2003
• Technical audit April 2003
•  
• Call for tenders May to October 2003
•  
• Firm selection November 2003
•  
• Ordering December-January 2003
•  
• Construction and tests in the firm January 2003
  to February 2005
•  
• Delivery at Gran Sasso laboratory March 2005
•  
• Assembly, installation April 2005