Neutrino Extended Submarine Telescope with Oceanographic Research

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S. E. Tzamarias, Hellenic Open University for the
NESTOR Collaboration
Neutrino Extended Submarine Telescope with
Oceanographic Research
Operation and performance of the NESTOR test
detector
A measurement of the atmospheric muon flux with
the NESTOR test detector
NEUTRINO 2004 XXIst International Conference on
Neutrino Physics and Astrophysics
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NESTOR (NEUTRINO EXTENDED SUBMARINE TELESCOPE
WITH OCEANOGRAPHIC RESEARCH) G.
Stavrakakis Institute for Geodynamics, Athens
Observatory E. G. Anassontzis, A.
Manousakis-Katsikakis, L. K. Resvanis, G.
Voulgaris A. Aloupis, J. Kontaxis, S. Nounos, P.
Preve Physics Dept., University of Athens P.
Grieder, P. Minkowsky, M. Passera Physics Dept,
University of Bern A. Ball CERN G. Grammatikakis,
J. Gialas PhysicsDept., University of Crete P.
Katrivanos, I. Papazoglou, I Siotis NRCPS
DEMOKRITOS D. Korostylev, J. Makris, O. Vasiliev,
N.Zjabko Institute for Geophysics, University of
Hamburg J. G. Learned, S. Matsuno, R. Mitiguy, M.
Rosen Dept. of Physics and Astronomy,University
of Hawaii E. Fahrun, G. Green, U. Keussen, Th.
Knutz, P. Koske, J. Rathlev, Th. Schmidt, D.
Eilstrup, J. Mielke, N. Schmidt, W.
Voigt Institute of Experimental and Applied
Physics, Center for Applied Marine Sciences
Research and Technology Center West Kueste ( FTZ
Buesum) University of Kiel W. Chinowsky, J.
Ludvig, D. Nygren, G. Przybylski, J. Sopher, R.
Stokstad Lawrence Berkeley National Laboratory E.
Markopoulos, K. Papageorgiou, L.K. Resvanis, T.
Staveris, V. Tsagli N. Arvanitis, A. Babalis, A.
Darsaklis, J. Kiskiras, G. Limberopoulos, Th.
Michos, J. Tsirmpas, A. VougioukasNESTOR
Institute for Deep Sea Research, Technology and
Neutrino Astroparticle PhysicsP.E.
Christopoulou, Ch. Goudis, C. PolitisPhysics
and Astronomy Dept., University of Patras G.
Agouras, B. Verganelakis, G. Bourlis,, A. Leisos,
A. Tsirigotis, S. TzamariasSchool of Science and
Technology, Hellenic Open University Ch.
Eleftheriadis,Ch. Lazaridis, M. Myronakis, A.
Nikolaidis, M. Tsiakiris Department of Physics,
Aristotelian University of Thessaloniki V.V.
Ledenev O. Vaskine, K. Komlev Experimental Design
Bureau of Oceanological Engineering A.V.
Butkevich, L.G. Dedenco, S.K. Karaevsky, A.
Mironovich, N.M, Surin, I.M. Zheleznykh, V.
A.Zhukov L.M. Zacharov, A. Shnyrev Institute For
Nuclear Research , Russian Academy of Sciences
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The NESTOR Neutrino Telescope Site

• Site characteristics
• a broad plateau 8x9 km2 in area, 7.5 nautical
  miles from shore
• depth 4000m (?5200m)
• transmission length 55 10m at ?460 nm
• underwater currents lt10 cm/s measured over
  the last 10 years
• optical background 50 kHz/OM due to K40 decay
  bioluminescence activity (1 of the experiment
  live time)
• sedimentology tests flat clay surface on sea
  floor, good anchoring ground.

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NESTOR DETECTOR
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ReadOut Electronics DAQ Chain
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Ti-Sphere Electronics
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DAQ Architecture
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Detector Preparation
Functional Tests Triggering Signal
deformation Digitization DAQ performance
L.E.D.
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Real Time Monitor

• Environmental
• Thermometers
• Hygrometers
• Compass
• Inclinometer/Accelerometer
• Pressure meter
• Electrical
• PMT High Voltage etc
• Digitization DAQ Performance
• Digitized waveforms
• PMT rates
• Trigger rates
• DAQ status

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Data Analysis Flow
Raw Data
Interface
Waveform Reconstruction
Data Quality Histograms
Hit Definition
Software Monitor Histograms
Database (gains,
baselines,attenuation etc)
DST Production
Track Reconstruction
Calibration Data Analysis
MiniDST Ntuples Histograms
Calibration Database Quality Histograms
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K40 Background A stable calibration source
Calibration
Data from a depth of 3800 m PMT Pulse Height
Distribution
single p.e. LED Run
single p.e. pulse height distribution two p.e.s
pulse height distribution dark current pulse
height distribution sum of the above
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Data from a depth of 3800m
Single PMT Rates
Trigger 4fold Coincidence
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Data from a depth of 3800 m
Bioluminescence Occurs for the 1.1 0.1
of the
Active Experimental Time
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Data from a depth of 3800 m Calibration Run
Calibration Data Analysis
Calibration Database Quality Histograms
LED Calibration Data Gain Monitors
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Data from a depth of 3800 m Trigger Studies
Data Collected with 4fold Majority Trigger
c
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Data from a depth of 3800 m Trigger Studies
Data Collected with 4fold Majority Trigger
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Charge Timing information
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Track Fit Using the Pulse Arrival Time
texpf(?,f,Vx,Vy,Vz)
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Run 63_37 Event 396
Fit Results
c
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Track Selection According to the Photon-Likelihood
Fit Strategy
Photon-Likelihood
Pi(µexp,Vmeas) is the probability the pulse
height of the ith PMT to be Vmeas while the
expected mean number of photoelectrons is equal
to µexp
Where Ri(On) is the (normalized to unity) pulse
height distribution of the ith PMT which
corresponds to n photo-electrons
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c
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Fit Strategy Summary
Pulse Arrival Timing Information
Pulse Height Information
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Apply quality cuts to improve resolution
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Reconstruction Accuracy

• ?2 probability gt 0.1
• track selection according to the
  photon-likelihood
• more than 4 p.e.s per hit per track
• impact parameter gt 6 meters

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Raw Data
Zenith Angle Distribution (atmospheric
muons)
745 Data events
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Raw Data
Azimuth Angle Distribution (atmospheric
muons)
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Determination of Cosmic Muon Flux
Extended binned likelihood estimation
by reweighting the Monte Carlo events
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Determination of Cosmic Muon Flux
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Determination of Cosmic Muon Flux
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Comparison with other experiments and
phenomenological predictions
Edgar V. Bugaev, et al, Physics Review D58,
054001 (1998).
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• Conclusions
• The objectives for the deployment of the NESTOR
  test detector concerning
• a thorough test of,
• the electrical supply and distribution systems
• the monitoring and control systems
• the full data acquisition and transmission chain
  from the sea to the shore station
• the demonstration of the ability of the proposed
  neutrino telescope to reconstruct muon
  trajectories,
• were met successfully.

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Autumn 2004 Deep-sea deployment run 4-floors
Physics Run
Autumn 2006 Full tower deployment in deep sea
Physics Data Taking

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15 of a Km2 NESTOR Detector
2006 Deployments of more
towers e.g. 7
towers (1176 PMTs) 3 strings (72 PMTs)
1.8 Megatons of DENSILY
instrumented mass within
the 7 towers (i.e. few GeV threshold)

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Example Eff Area Calculation
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Status
built in Pylos
3 DUMAND STRINGS INCLUDING "CHIRPED SONAR"i.e.
POSITIONING lt A FEW cms