OPERA O scillation P roject with E mulsion-t R acking A pparatus

1. OPERA Oscillation Project with Emulsion-tRacking Apparatus LNGS and the Neutrinos from CERN

2. Brussels Bern Neuchatel Zurich IPNL, IRES, LAPP INR ITEP JINR, Obninsk Zagreb Hamburg, Münster, Rostock Sofia IHEP Beijing Shandong Aichi, Toho Kobe, Nagoya Utsunomiya L’Aquila, Bari, Bologna, Napoli, Padova, Roma, Salerno, LNF, LNGS Technion Haifa Gyeongsang University 37 INSTITUTIONS, ~160 PHYSICISTS METU Ankara OPERA is an International Collaboration LNGS and the Neutrinos from CERN

3. Brussels Bern Neuchatel Zurich IPNL, IRES, LAPP INR ITEP JINR, Obninsk Zagreb Hamburg, Münster, Rostock Sofia IHEP Beijing Shandong Aichi, Toho Kobe, Nagoya Utsunomiya L’Aquila, Bari, Bologna, Napoli, Padova, Roma, Salerno, LNF, LNGS Technion Haifa Gyeongsang University 37 INSTITUTIONS, ~160 PHYSICISTS METU Ankara OPERA is an International Collaboration LNGS and the Neutrinos from CERN

4. Neutrinos Oscillations : Flavor change for massive Neutrinos This property of massive neutrinos has been proposed by B. Pontecorvo (1950) • After 50 years of a long search with various experimental technics • Solar neutrinos (i.e. GALLEX at LNGS) • Atmospheric neutrinos (i.e. MACRO at LNGS) • Nuclear Reactors neutrinos • Accelerator neutrinos • The existence of the Neutrinos Oscillations has been established LNGS and the Neutrinos from CERN

5. What is the goal of OPERA • Once the oscillations established, a large international program has been set for checking all parameters of the flavor transitions: • Japan ( KEK to Super-Kamiokande) , US ( Fermi Lab to MINOS ) • μdisappearance • Europe ( CERN to Gran Sasso ) • τappearance  OPERA LNGS and the Neutrinos from CERN

6. - n Decay “kink” nm - nm oscillation n t- nt ~1 mm Detection of the nt appearance signal The challenge is to identify ntinteractions from ninteractions Toplogy selection:  Kink signature • Two conflicting requirements: • Large mass  low Xsection • High granularity  signal selection  background rejection • Target:1800 tons, 5 years running • 30 000 neutrino interactions • ~150 ntinteractions • ~15 nt identified • < 1 event of background LNGS and the Neutrinos from CERN

7. 1 mm t n 8.3 Kg  Interaction From NUMI exposure Pb Emulsion layers 10.2cm 12.5cm Electron shower OPERA bricks 1 ECC= 56 Pb + 57 emulsions • ECC : target basic component • Em Provides high space resolution • + Lead active target mass • Compact and modular structure 10 X0’s 2 emulsion layers (44 m thick) poured on a 200 m plastic base LNGS and the Neutrinos from CERN

8. 8 cm Electronic detectors: Emulsion analysis: Vertex, decay kink e/gID, multiple scattering, kinematics 8 m Spectrometer Target Trackers Pb/Em. target supermodule Link to mu ID, Candidate event Pb/Em. brick Basic “cell” Pb Emulsion 1 mm Extract selected brick Brick finding muon ID, charge and p OPERA/CNGS1 : an hybrid detector • What the brick cannot do: • trigger for a neutrino interaction • muon identification and momentum/charge measurement need for an hybrid detector LNGS and the Neutrinos from CERN

9. Structure of the OPERAExperiment 31 target planes / supermodule (in total: 206336 bricks, 1766 tons) SM1 SM2  Magnetic Spectrometers Targets Proposal: July 2000, installation at LNGS started in May 2003 First observation of CNGS beam neutrinos : August 18th, 2006 LNGS and the Neutrinos from CERN

10. details of the first spectrometer OPERA Super-module OPERA Trackers in pictures & numbers 5900 m² scintillator detectors – 3050 m² Resistive Plate Chambers 8064 7m long drift tubes - ~2000 tons of Fe LNGS and the Neutrinos from CERN

11. 10.5 ms 10.5 ms 50 ms August 2006 : first neutrinos from the CNGS detected LNGS and the Neutrinos from CERN

12. Event selection by using GPS timing informations Ext2 Ext1 10 ms 50 ms Zoom on the spill peaks Δt first extraction (ns) Cosmic rays background events Δt closest extraction (ns) LNGS and the Neutrinos from CERN

13. Beam event CC event originated from material in front of the detector (BOREXINO, rocks) LNGS and the Neutrinos from CERN

14. CC event in the first magnet LNGS and the Neutrinos from CERN

15. CC event in the first target LNGS and the Neutrinos from CERN

16. Muons bundle from cosmic rays Cosmic rays event can be easily isolated using their topology Cosmic rays induced events: Mostly down going Beam events: ~horizontal tracks LNGS and the Neutrinos from CERN

17. Conclusions • The CNGS beam is operating smoothly with very good quality • The tracking detectors of OPERA are taking data with practically no dead time • More than 300 beam correlated events have been registered with a clean time distribution • The recorded events show the expected tracking performances • Correlation between tracks measured in the tracking detectors and emulsions installed in the target have been observed • OPERA is now preparing the next step: •  observing neutrino interactions in the Emulsion Cloud Chamber bricks • Next step : end of october run !!! LNGS and the Neutrinos from CERN

18. BAM wrapping section CS box Brick Brick production BAM piling/pressing section Emulsion films • Starting now: • 12 106 emulsions & lead plates • 200 000 bricks to be produced • production rate : 1000/day • 10 months • for filling the detector Lead boxes LNGS and the Neutrinos from CERN

19. Brick insertion, extraction, processing, Brick Manipulating System Vacuum sucker vehicle Emulsion developping lab LNGS and the Neutrinos from CERN

20. Event reconstruction in the brick LNGS and the Neutrinos from CERN

21. The messenger of the stars is revealing great and wonderful spectacles and incite everyone to look up at these … For 50 years, by recording neutrinos from the sun, the Super-Novae, cosmic rays we improved our understanding in Astrophysics and Cosmology In addition, neutrinos gave us a present by revealing their properties: this is opening a new field of research in fondamental physics for the next 50 years which will also have profound consequences in the understanding of the Universe LNGS and the Neutrinos from CERN