1. Απόστολος Τσιριγώτης Αξιολόγηση Αρχιτεκτονικών και Υποθαλάσσιων Περιοχών Εγκατάστασης για ένα Μεγάλο Μεσογειακό Τηλεσκόπιο Νετρίνων Α. Τσιριγώτης Β. Βεργανελάκης, Α. Λέισος, Γ. Μπουρλής,, Α. Σκόδρας, Σ. Τζαμαρίας

2. The HOU software chain Underwater Detector Generation of atmospheric muons and neutrino events (done – Techn. Note) Detailed detector simulation (GEANT4) (done – Techn. Note) Optical noise and Photomultiplier (PMT) response simulation (done) Filtering Algorithms (done – Techn. Note) … Muon reconstruction (done – Techn. Note) … Calibration (Sea top) Detector Atmospheric Shower Simulation (done – Techn. Note) Muon and Neutrino Transportation to the Underwater Detector (done) Reconstruction of the shower direction (done – Techn. Note) … Estimation of: resolution, offset, PMT position (done – 2 draft papers in NIM ) Code will be available at http://physicslab.eap.grhttp://physicslab.eap.gr Documentation in progress

3. Event Generation – Flux Parameterization Neutrino Interaction Events Atmospheric Muon Generation (2 Parameterization Models) μ Atmospheric Neutrinos ν ν Cosmic Neutrinos Earth Shadowing of neutrinos by Earth Nadir Angle Probability of a ν μ to cross Earth

4. GEANT4 Simulation – Detector and Physics Description Any detector geometry can be described in a very effective way All the relevant physics processes are included in the simulation GEANT4 Simulation – Primary Particles Any type of secondary particle and it’s interactions is simulated All the interactions and transportations of the secondary particles are simulated For the simulation of the neutrino nucleon interaction PYTHIA is used GEANT4 Simulation – Fast Simulation techniques Electromagnetic Shower Parameterization Simulation of optical photons continues after emission only when there is a significant probability for the photon to hit a PMT GEANT4 Simulation : Visualization Particle tracks, detector components and hits are visualized using Virtual Reality Modeling Language (VRML)

5. GEANT4 Simulation – Example: Charge Current Atmospheric ν e (20GeV) interaction Detector Geometry Optical Module Geometry 1km3 Grid with 18522 PMTs Particle Tracks Hits PMT Photocathod

6. PMT Collective Efficiency PMT Single Photoelectron Spectrum mV PMT Quantum Efficiency PMT Standard electrical pulse for a response to a single p.e. PMT Arrival Pulse Time resolution Optical noise and PMT response simulation Radioactive decays in water

7. Simulation Example 1km3 Grid - 1 TeV Vertically incident muon K 40 Noise Hits Signal Hits (Hit amplitudes > 2 photoelectrons) Electrical Pulse of a Noise Hit

8. Filtering & Reconstruction Algorithms Local (storey) Coincidence filter Applicable only when there are more than one PMT looking towards the same hemisphere Global clustering (causality) filter 50% Background rejection while all signal hits survive (1km3 Grid & 1 TeV muon) Local clustering (causality) filter 75% Background rejection while 90% of signal hits survive (1km3 Grid & 1 TeV muon) Prefit : Clustering of candidate tracks Angular deviation (degrees) 1TeV muons 1km3 Grid Detector Fit:Kalman Filter (novel application in this area) Angular deviation (degrees) 1TeV muons 1km3 Grid Detector PRELIMINARY

9. The HELYCON Detector Module: CONSTRUCTION SC-301 Protvino BICRON BCF91A 12 fibers/column TYVEC 4650B PH: XP1912 10 x 12 cm tiles 2x80 tiles ~ 0.96 m 2

10. Response to a MIP DAQ S/W based on LabView On-Line analysis - distributions Charge (in units of mean p.e. charge) At the Detector Center  Data - Monte Carlo Prediction Detailed Monte Carlo description PRELIMINARY Digitized Waveforms saved on hard disk

11. Response to Showers Data versus Monte Carlo Prediction PRELIMINARY deposited charge per counter [mip equivalent]  Data ___ M.C. Prediction zenith angle (θ) φ Observed Rates: 2500 (± 30 ) per day Predicted Rates: 2430 (± 100 M.C. stat.) per day

12. Response to Showers Trigger Detectors >1 mip Detectors A.and.B > 0.5 mip’s zenith angle [degrees] Trigger Detectors > 1 mip Detectors A.and.B > 1.5 mip’s α=9.4±0.2 PRELIMINARY

13. Measuring the angular resolution of a single station Discriminator (1.5 MIP) Input C Trigger Input B Input A’ Input A Input B’ Detector I: A, B,C Detector II: A’, B’,C ~10m between detectors θ Ι -θ ΙΙ M.C. Prediction 10m lever arm 6.8 o ·(2) 1/2 =9.6 o

14. HELYCON HELLENIC LYCEUM COSMIC OBSERVATORIES NETWORK 10 19 eV 10 17 eV 10 15 eV 2 km

16. The General Idea… Angular offset Efficiency Resolution Position but also Physics … C.R. composition UHE ν - Horizontal Showers Veto atmospheric background – Study background We propose a minimum of 3 stations with at least 4 m 2 scintillator detectors each Floating stations (Sea Technology?)

17. Monte Carlo Studies Reconstruction efficiencyResolution (degrees) Three Stations Working Independently for 10 days Single Station: 4 detectors (1m 2 plastic scintillator), 20 m distance between the detectors, three out of four selection trigger PRELIMINARY Minimum of total collected charge [mip equivalent] zenith angle resolution [degrees]

18. KM3NeT Kick-off Meeting, 11-13 April 2006, University of Erlangen-Nuremberg, Germany (1. Simulation and Reconstruction Algorithms, 2. Event Selection Criteria and Filters and 3. Calibrating the KM3 Telescope with EAS ) HEP2006: Recent Developments in High Energy Physics and Cosmology, April 13-16 2006, Ioannina, Greece (1. Neutrino Telescopy and EAS, 2. Data Analysis Techniques for the KM3NeT and 3. Using HELYCON as a calibrating system) 20 th European Cosmic Ray Symposium, September 5th-8th 2006, Lisbon, Portugal (HELYCON Detector: A status report) 6th International Workshop on the Identification of Dark Matter (IDM 2006), 11-16 September 2006, Rhodes Greece (Towards a SeaTop Infrastructure) KM3NET Physics and Simulation Meeting (WP2), 24-25 October 2006, CPPM Marseilles France (H.O.U. Analysis and Simulation Tools) KM3NET WP3 Meeting, 8-10 November 2006, Paris (KM3NeT: calibration with atmospheric showers) Contributions to International Workshops and Conferences 2 nd Workshop on Cosmic Rays in Schools Projects, September 9th 2006 Lisbon Portugal (HELYCON: as an Outreach and Educational program ) Publications A. Tsirigotis, “HELYCON: A Status Report”, Proceedings of the 20 th European Cosmic Ray Symposium S.E.Tzamarias, “HELYCON: towards a sea top infrastructure”, Proceedings of the 6th International Workshop on the Identification of Dark Matter D. Loukas et al, “HELYCON Readout Electronics”, to be published. A.Leisos et al, “KM3NeT: Calibration with Atmospheric Showers”, to be published (NIM) A.Tsirigotis et al, “The HELYCON Detector”, to be published in Astr. Phys.