# VLVnT08

Europe/Paris
Palais Neptune Conference Center, Toulon

#### Palais Neptune Conference Center, Toulon

Palais des Congrès Neptune Place de Besagne Centre Commercial Mayol
Participants
• alain calzas
• alain cosquer
• alain maguer
• ALAIN MAZURE
• Alexander Kappes
• Anastasios Belias
• Andrea Bersani
• Andreas Psallidas
• Andrew Taylor
• Angelo Orlando
• Angélique PEPE
• Annarita Margiotta
• Anne Holford
• Anne-Gaelle dehaine
• Anthony Ehret
• Antoine Kouchner
• Antonio Capone
• Antonio D'Amico
• Apostolos Tsirigotis
• AUDRIC Max
• Bayarto Lubsandorzhiev
• Bertrand Vallage
• Brendan Fox
• BRUN GUILAUME
• Bruno COMBETTES
• Carl GOJAK
• Chantal RACCA
• Christian Curtil
• Christian Joram
• Christian Spiering
• Christopher Naumann
• Claudio Kopper
• Corey Reed
• damien dornic
• David Hilbeck
• Davide Piombo
• Diego Torazza
• Dirk Hoffmann
• Dmitri Semikoz
• Domenico Lo Presti
• Doug McGowen
• Elisa Resconi
• EMANUELE LEONORA
• Emmanuel Decugis
• Emmanuel Grassal
• Eric Kajfasz
• Etienne Parizot
• Fabrice Gensolen
• Fabrizio Ameli
• Francesco Simeone
• Francisco Salesa
• Francoise Genova
• François FOUCHE
• FRESEL Bruno
• Gabriele Giovanetti
• Gabrielle Lelaizant
• George Bourlis
• Gerald Abich
• Gerard van der Steenhoven
• Giorgio Riccobene
• Gisela Anton
• Graham Sperrin
• Gregory Hallewell
• Guillaume Lambard
• Henk Peek
• Henrik Bang-Andreasen
• Herbert Loehner
• Igor Belolaptikov
• Imen Al Samarai
• INGRID PUILLAT-FELIX
• Isabella Amore
• Jean Marvaldi
• Jean Roux
• Jean-Charles LEFORT
• Jean-Jacques Destelle
• Jelle Hogenbirk
• Jessica Craig
• John Carr
• Jonathan Perkin
• Jose Busto
• Juergen Brunner
• Katia Fratini
• Kevin Hall
• Kurt LUND
• Laurence Caillat
• Laurie DOYLE
• Lee Thompson
• LOUIS Frederic
• Luciano Moscoso
• Luke Drury
• MANOLIS MANIATIS
• Mar Van der Hoek
• Marco Circella
• Maria (Maya) Stavrianakou
• Maurizio Spurio
• Mauro Morganti
• Mauro Taiuti
• Maximilien MELISSAS
• Megna Rosario
• Michel AGERON
• Michel André
• Michel Billault
• Miguel Ardid
• Nicolas Picot Clemente
• Nunzio Randazzo
• Oleksiy Kebkal
• Paolo Favali
• Paolo Piattelli
• Pascal Vernin
• Pascale Keller
• Paschal Coyle
• Peter Healey
• Peter Jansweijer
• Petros Rapidis
• Phetnila Thammavongs
• Philippe Lagier
• Piera Sapienza
• Ralf Auer
• Ralf Wischnewski
• Rezo Shanidze
• Robert Lahmann
• Rocco MASULLO
• Ronald Stubberfield
• Ronan LOCHOUARN
• Ronan MICHEL
• Rosa Coniglione
• Rosanna Cocimano
• Rosario Megna
• S. Martin Taylor
• Sander Mos
• Shebli Anvar
• Siegfried Schmid
• Simona Toscano
• Spyridon Koutsoukos
• Spyros Tzamarias
• Stefano Russo
• Stephan Beurthey
• Stephanie Escoffier
• Steven Barwick
• Steven Thumbeck
• Sylvain Henry
• Theodoros Athanasopoulos
• Thomas Eberl
• Ulf Fritsch
• Uli Katz
• Vincent BERTIN
• Vincenzo Flaminio
• Yuji Hotta
• Yuji Yoshizawa
• Zhi-zhong Xing
• Monday, 21 April
• 18:00 20:00
Welcome cocktail and Registration 2h
• Tuesday, 22 April
• 08:30 12:00
Registration 3h 30m
• 09:00 18:30
Plenary Session I Salle Colbert

### Salle Colbert

#### Palais Neptune Conference Center, Toulon

Palais des Congrès Neptune Place de Besagne Centre Commercial Mayol

Chairs: Luciano Moscoso (APC Paris): Morning Session, Luke Drury (IAS Dublin): Afternoon Session

• 09:00
Introduction and Welcome 30m
• Introduction and Welcome 10m
Director of Centre de Physique des Particules de Marseille, host institute for the ANTARES underwater neutrino telescope
Speaker: Eric KAJFASZ (CPPM)
Sénateur-Maire du Var, la Valette du Var, Première Vice-Présidente de la communauté d'agglomération Toulon-Provence-Méditerrannée, responsible for Economic Development
Speaker: Christiane HUMMEL
• 09:30
Status of the ANTARES underwater neutrino telescope 40m
ANTARES (Astronomy with a Neutrino Telescope and Abyss environmental RESearch) is the largest neutrino detector currently operating in the Northern Hemisphere. The detection principle relies on the observation of Cerenkov light emitted by muons resulting from charged current neutrino interactions in the water surrounding the detector and the seafloor below. The full apparatus will comprise twelve detection lines (each carrying 75 photomultipliers distributed over 25 triplets) and one instrumented line (mainly devoted to measurements of the environmental conditions and hosting prototype instrumentation for acoustic detection of particles), placed at a depth of about 2480 m 40 km off the coast of Toulon, France. Ten detection lines and the instrumented line are in operation since December 2007. The apparatus is expected to be completed in the course of 2008. In this presentation, we will illustrate the main features of the apparatus and discuss its performance and capabilities.
Speaker: Marco CIRCELLA (INFN Bari)
• 10:10
Status and prospects of IceCube neutrino telescope 40m
The IceCube neutrino observatory, under construction at the South Pole, consists of three sub-detectors: a 3-dimensional array of digital optical modules deployed deep in the ice, the AMANDA neutrino telescope and the surface array IceTop. I will summarize results from searches for cosmic neutrinos with the AMANDA telescope and review expected sensitivities for IceCube at various installation phases. Reliability and robustness of installation at the South Pole has been demonstrated along the past four construction seasons. On the base of a consolidated confidence in operations at the South Pole, the extension of IceCube operations at the extreme ends (low and high) of the energetic region can be accomplished. I will describe the IceCube Deep Core project that will extend the low energy response of IceCube and a study of optimal positioning of outer most strings for a better sensitivity at higher energies.
Speaker: Elisa RESCONI (MPI Heidelberg)
• 10:50
coffee break 30m
• 11:20
The BAIKAL neutrino experiment: status, selected physics results, and perspectives 30m
We review the status of the Baikal Neutrino Telescope, which is operating in Lake Baikal since 1998 and has been upgraded to the 10 Mton detector NT200+ in 2005. We present selected physics results on searches for upward going neutrinos, relativistic magnetic monopoles and for very high energy neutrinos. Recent results of R&D activities towards a km3 Baikal neutrino telescope are discussed
• 11:50
EMSO: the European Multidisciplinary Seafloor Observation 40m
EMSO is a Research Infrastructure listed within ESFRI, and will be based on a European-scale network of multidisciplinary seafloor observatories from the Arctic to the Black Sea with the scientific objective of long-term real-time monitoring of processes related to geosphere/biosphere/hydrosphere interactions. GMES has identified a need for a seafloor segment complementary to land and space borne systems. EMSO will enhance our understanding of processes through long time series appropriate to the scale of the phenomena, constituting the new frontier of studying Earth interior, deep-sea biology and chemistry and ocean processes. The EMSO development is based on the synergy between the scientific community and the industry to improve the European competitiveness with respect to countries like USA, Canada and Japan. The development of an underwater network is based on previous EU-funded projects and is being supported by several EU initiatives, as the on-going ESONET-NoE, coordinated by IFREMER, and aims at gathering together the Community interested in ocean observatories. The FP7 Capacities Programme launched in 2006 a call for Preparatory Phase (PP) projects, that will provide the support to create the legal and organisational entities in charge of managing the infrastructures, and coordinating the financial effort among the countries. EMSO-PP project, approved in 2007, has just started in April 2008 (4 years, coordinated by INGV with other 11 Institutions of 11 countries)
Speaker: Paolo FAVALI (INGV Rome)
• 12:30
lunch break 1h 30m
• 14:00
The Status of Very High Energy Gamma-ray Astronomy as of early 2008 30m
After more than 2 decades of gestation the atmospheric chernkov technique has reached the maturity age. Obsevations in the very high energy gamma-ray band with the new generation of imaging telescopes, in particular the galactic plane scan by HESS, low threshold observations with MAGIC and more recently operation of VERITAS, have revealed few tens of sources in the galactic and extragalactic domains, providing a wealth of information on a variety of high energy accelertion sites in our universe. Also, the water Cherenkov instrument MILAGRO is providing its first results after seven years of data integration. An overview of these results with a focus on the most interesting ones will be given. The future projects at short and medium timescales will then be discussed briefly.
Speaker: Arache DJANATTI-ATAI (APC Paris)
• 14:30
Status of extensive air shower studies at Auger 30m
The current status of the Pierre Auger Observatory will be described and the main results gathered so far about arrival directions, energy spectrum and composition will be presented, including the current limit on the high-energy neutrino flux. Implications for the future development of high-energy cosmic ray astrophysics will also be discussed.
Speaker: Etienne PARIZOT (Paris-7)
• 15:00
Status of the KM3NeT project 30m
KM3NeT is a future research infrastructure in the Mediterranean Sea, hosting a cubic-kilometre-scale neutrino telescope and nodes for associated sciences such as marine biology, oceanology and geophysics. The status of the KM3NeT project and the progress made in the EU-funded Design Study will be reviewed. The KM3NeT Conceptual Design Report (CDR), summarising the design options to be further pursued, will for the first time be presented to the public. Finally, the remaining steps towards construction, and in particular the objectives of the FP7 Preparatory Phase project will be discussed.
Speaker: Ulrich KATZ (Friedrich-Alexander Universitat Erlangen-Nurnberg)
• 15:30
Status of the NEMO Project 30m
The NEMO collaboration has conducted in the recent years an intense R&D activity directed at the realization of an underwater km3 Cherenkov detector for the detection of high energy astrophysical neutrinos. The activities have addressed some key issues such as the search and characterization of an optimal deep-sea site for the detector installation, the definition of the detector architecture, the design of the detector components and the realization of prototypes. The recent completion of the Phase-1 project with the installation and connection at the LNS Underwater Test Site of a Junction Box and a prototype detector tower has proved the effectiveness of the technological solution proposed as well as a validation of the underwater connection procedure by means of a surface controlled Remotely Operated Vehicle. Preliminary results from the first five months of operation of the apparatus will be presented. The following step will be a Phase-2 project aiming at the realization of a deep-sea station at 3500m depth on the Capo Passero candidate site. The realization of the infrastructures needed for Phase-2 operation, including the submarine cable and shore station, is under way and will be completed in early 2008. This will be followed by the construction and installation of a full-size detector tower by the end of 2008.
Speaker: Prof. Antonio CAPONE (Physics Department, University "Sapienza" and INFN, Roma)
• 16:00
Coffee break 30m
• 16:30
Status of the NESTOR underwater neutrino telescope 30m
The NESTOR collaboration is continuing its efforts towards deploying a larger portion of its proposed tower detector. Following the successful deployment of a single floor of the tower in 2003, five floors are now in the final stages of preparation. These floors, together with two autonomous strings to be located some 300 m away from the tower form the detector proposed by the NuBE collaboration, whose aim is to detect neutrinos in coincidence with Gamma Ray Bursts. The NuBE experiment will be described, as well as recent activities that include further site studies (e.g. water light transmission measurements, sedimentation rates, etc.), and plans on using the soon-to-be-available deployment platform Delta-Bereniki.
Speaker: Petros RAPIDIS (INP Demokritos, Greece)
• 17:00
Flavor Distribution of UHE Neutrino Oscillations at Neutrino Telescopes 30m
If the ultrahigh-energy (UHE) neutrino fluxes produced from a distant astrophysical source can be measured at a km^3-size neutrino telescope, they will provide a promising way to help determine the flavor mixing pattern of three active neutrinos. Considering the conventional UHE neutrino source with the flavor ratio \phi_e : \phi_\mu : \phi_\tau = 1 : 2 : 0, I will show that \phi_e : \phi_\mu : \phi_\tau = (1 -2 \Delta) : (1 +\Delta) : (1 +\Delta) holds at the detector of a neutrino telescope, where \Delta characterizes the effect of \mu-\tau symmetry breaking (i.e., \theta_{13} \neq 0 and \theta_{23}\neq \pi/4). Current experimental data yield -0.1 \leq \Delta \leq +0.1. Furthermore, I will propose a parametrization for the flavor composition of UHE neutrino fluxes produced from an arbitrary astrophysical sources: \phi_e : \phi_\mu : \phi_\tau = \sin^2 \xi \cos^2 \zeta : \cos^2 \xi \cos^2 \zeta : \sin^2 \zeta. I show that it is possible to determine or constrain \xi and \zeta by observing two independent neutrino flux ratios at neutrino telescopes, provided three neutrino mixing angles and the Dirac CP-violating phase have been well measured in neutrino oscillations. Any deviation of \zeta from zero will signify the existence of cosmic \nu^{}_\tau and \overline{\nu}^{}_\tau neutrinos at the source, and an accurate value of \xi can be used to test both the conventional mechanism and the postulated scenarios for cosmic neutrino production.
Speaker: Prof. Zhi-Zhong XING (Institute of High Energy Physics, Chinese Academy of Sciences)
• 17:30
Transformative Ocean Science through the VENUS and NEPTUNE Canada Ocean Observing Systems 30m
The health of the world’s oceans and their impact on global environmental and climate change make the development of cabled observing systems vital and timely as a data source and archive of unparalleled importance for new discoveries. The VENUS and NEPTUNE Canada observatories are on the forefront of a new generation of ocean science and technology. Funding of over 100M, principally from the Governments of Canada and BC, for these two observatories supports integrated ocean systems science at a regional scale enabled by new developments in powered sub-sea cable technology and in cyber-infrastructure that streams continuous real-time data to Internet based web platforms. VENUS is a coastal observatory supporting two instrumented arrays in the Saanich Inlet, near Victoria, and in the Strait of Georgia, off Vancouver. NEPTUNE Canada is an 800km system on the Juan de Fuca Plate off the west coast of British Columbia, which will have five instrumented nodes in operation over the next 18 months. This paper will describe the development of these two observatories, the principal research themes, and the applications of the research to public policy, economic development, and public education and outreach. Both observatories depend on partnerships with universities, government agencies, private sector companies, and NGOs. International collaboration is central to the development of the research programs, including partnerships with initiatives in the EU, US, Japan, Taiwan and China. Speaker: Stephen M. TAYLOR (Ocean Networks Canada) • 20:00 23:00 Conference Banquet 3h • Wednesday, 23 April • 08:30 16:05 Parallel session on Engineering for deep deployment neutrino telescopes Salle Colbert ### Salle Colbert #### Palais Neptune Conference Center, Toulon Palais des Congrès Neptune Place de Besagne Centre Commercial Mayol • 08:30 Low Power Multi-Dynamics Front End Architecture for the Optical Module of a Neutrino Underwater Telescope 10m A proposal for a new front-end architecture intended to capture signals in the optical module of an underwater neutrino telescope is described. It concentrates on the problem of high dynamic range, power consumption, signal reconstruction, charge and time precision. Preliminary test results on a demonstration board are shown. Speaker: Dr Domenico Lo Presti (Catania University) • 08:40 Time over Threshold electronics for an underwater neutrino telescope 10m The use of Time over Threshold (ToT) digitization techniques for the treatment of the output signal of the PMTs of the KM3NeT detector is under consideration by the KM3NeT collaboration. In this technique the leading and trailing edge of the signal above a certain threshold are time stamped and the corresponding times are sent to the onshore acquisition system. More information can be obtained by applying the same scheme at multiple threshold levels. In this note we present the efficiency of such a digitization technique applied to signals provided by the HEllenic LYceum Cosmic Observatories Network (HELYCON) Extensive Air Shower detector. The hardware used has been designed by the Hellenic Open University (HOU) group and it is based on a High Precision Time to Digital Converter (HPTDC) chip developed at CERN and offering up to 32 channels with a digitization accuracy of 100ps. We describe the operation and performance of these electronics and we evaluate the reconstruction accuracy of PMT signals using data collected from Extensive Air Showers. Finally we report on our plans to use these electronics on Optical Modules proposed to be used in KM3NeT. Speaker: Mr George Bourlis (Hellenic Open University) • 08:50 The NEMO-Phase2 data acquisition and transmission system 10m This work presents a new electronic board which will equip two experimental floors on the NEMO Phase-2 tower which will be deployed at Capo Passero. This board integrates the front-end electronics for PMT signal acquisition, the floor communication interfaces with environmental instruments, the interface with a hydrophone board and the high speed communication link with the tower backbone, i.e. with the on-shore lab. Inheriting the NEMO Phase-1 experience, the link will be realized using a synchronous protocol which embeds clock and data. The front-end is realized sampling at 200 MHz the PMT analog signal with fast ADCs endowed with a high dynamic range (14 bit) and very low power consumption. Because of the high speed proprietary protocol, a counterpart board is needed on shore to allow data exchange with floor electronics; this board (which at a very first step can be the same off-shore board) provides also the interface toward the experiment control system, the trigger architecture and the timing station which provides a time reference synchronous to the GPS time. Speaker: Dr Gabriele Giovanetti (INFN) • 09:00 Qualification tests and readout electronics reliability analysis for the deep sea underwater telescope NEMO 10m The construction of a Km3 scale underwater telescope for high energy neutrinos is a fundamental task for the development of - high energy neutrino astronomy. The NEMO collaboration is involved in an intense activity to develop, apply and test technical solutions for a deep underwater laboratory devoted to study the high energy neutrino component of cosmic rays. In this framework the front-end and readout electronics are some of the most important and delicate elements. This electronics must work properly for a long period of time (10 years) in an extremely hostile environment without any repair. For this reason high reliability is requested. In this work we present the test procedure and the reliability results of the NEMO readout electronics. Speaker: Dr Stefano Russo (Universita` di Napoli Federico II) • 09:10 Commodity, FPGA based, front end electronics for underwater neutrino telescopes 10m Usually the front end electronics required for a neutrino telescope, are electronics that perform waveform capture of analogue signals, optionally enforcement of a local triggering algorithm and transmission of the data to the shore. We show how a commodity system which employs COTS devices, like FADCs and FPGAs, can be used to perform such tasks to be used for multiple OMs' synchronous signal digitization at 250Ms/s with 8 - bit resolution. The transmission link to shore is implemented via a standard communication protocol (Gbit Ethernet through fibre). We describe the hardware and preliminary results from tests carried out at the Nestor Institute for Astroparticle Physics. Speaker: Mr Theodoros Athanasopoulos (NOA / IAF Nestor) • 09:20 short break 10m • 09:30 Proposal for a reconfigurable on-shore Data Acquisition system for km3 scale underwater Neutrino telescope. 15m The on-shore DAQ system for a km3 scale underwater Neutrino Telescope is required to read continuously the OMs (~10000) from the entire telescope and perform filtering and aggregation of the data to search for signatures of candidate muon and neutrino events. We propose the use of reconfigurable computing architecture to filter and route the continuous input data rates of about 1-10 Gb/s to processing units to apply calibration functions and triggering for event building, and arrive at an output event rate suitable for permanent storage to disk. Speaker: Anastasios BELIAS (NOA/NESTOR) • 09:45 KM3NeT: Real-time Opto-electronic Readout System 20m The purpose of this paper is to demonstrate that current optical communications technologies could be used to implement a real-time data transfer system for KM3NeT. We propose a solution based on Passive Optical Network principles (PONs) employing wavelength division multiplexing. A key feature of the design is that it does not employ remote light sources; instead a shore-based centralized array of lasers is shared by all of the telescope’s Optical Modules (OMs). Data (up to 10Gb/s) is transferred onto the optical carriers by means of high reliability, ultra-low electrical drive power, Reflection-mode Electro-Absorption Modulators (REAMs). In this way the electro-optic design of each OM is identical and they can be fitted in any position. (Each OM’s space-wavelength address is only set once it has been connected to the system.) This modular approach offers maximum flexibility for growth both in terms of telescope size and capacity. An example design will be described that can support up to10,000 OMs each serving 32 (or more) Photo-Multiplier Tubes (PMTs). We will describe how real-time readout and synchronisation is achieved and the details of the optical system design. The main advantage of this approach is that it minimises the amount of remote electronics, hence power consumption, and consequently maximises the telescope reliability and serviceability. The paradigm for the system is to consider KM3NeT as a giant photo-sensor that is readout on the shore. Speaker: Mr Peter Healey (CIP) • 10:05 Developments for a passive optical node network for deployment in deep sea enabling time synchronous data readout. 15m Today 100 optical specified ITU channels can fit into 1 single fiber. Today a 10Gb/sec. data rate per optical channel is common practice. This enables a transparent network with point to point connections from seabed to shore. Accurate timing, jitterless signal propagation, is intrinsic to an all optical system. Additional advantages of this node based passive optical approach are a long system life time and low power consumption on the seabed. A minimal need of offshore components eases developments, realizations and tests of the offshore electronics. The onshore electronics and data system can be developed separate and in parallel to the offshore system. Future developments and subsystems can be connected transparently on an optical channel up to 10Gb/sec. Speaker: Mr Jelle Hogenbirk (Nikhef) • 10:20 Photonic technologies for future Very Large Volume Neutrino Telescopes 10m Photonics, being a key technology in the present telecommunication networks already, will also strongly empower the realization of future very large volume neutrino telescopes. In general, photonics will serve as enabling technology in wide-area or large volume distributed networks for scientific research, connecting a large number of sensors to a central data collection centre. All-optical high-speed data-serialising, data transmission and data recovery enables more efficient data collection, higher data precision and allows new concepts for ‘collection of all data’. Novel network architectures and photonic components allow connection of more signal sources and expansion of the volume covered by the telescope. During assembly, deployment and operation of the telescope, photonic sensors can monitor structural parameters, like strain in the cables and humidity in electronic compartments. During operation, optimised sensor cables can monitor parameters in the direct environment of the telescope, such as e.g. temperature distributions or chemical parameters. The presentation will review some components and technologies for ‘all-photonics-based’ data collection and sensing in future very large volume neutrino telescopes. Speaker: Mr M.J. Van der Hoek (Nikhef) • 10:30 break 15m • 10:45 A low cost redundant store and forward DAQ system for KM3NeT, using copper in the Vertical String 15m The described system transports data from the Optical Modules to the on-shore data acquisition system using copper twisted pairs for the short runs and fiber optics for long distance to the Shore Station. VDSL2, developed for 'video to the home', provides > 100 Mbit/s bandwidth over a single twisted copper pair in the vertical string to transport all the data from an Optical Module to the Master Module. The same twisted pair is also used to transport power and timing to the Optical Module. All data communication, timing and timing calibration between the Shore Station and the Optical Modules as well as the distribution of power in the vertical string, is done via a single Master Module in the vertical string. A single channel of the long distance fiber optical DWDM system provides the data communication of a Master Module to the Shore Station. Reliability is a design issue of common infrastructure. A large part of the DWDM and the power system uses a common infrastructure. Each vertical line has two separate paths to the Shore Station via separate Junction Boxes. Destructive single point failures in the common infrastructure divide the system in two parts, but each part is independent fully functional. Speaker: Peter Jansweijer, P.P.M. (NIKHEF) • 11:00 A proposal design for data transmission system on copper backbone 20m The experience gained in previous experiments suggests to explore new ways of realizing the data transmission at the level of the detection unit (i.e. the string or the tower). The implementation of a copper connection with simple tracts of cable between contiguous storeys could provide an easier scalability of the structure, simple maintenance of the backbone, lower costs because of cheaper connectors, safer integration and transportation. This work is aimed at the presentation of an electronic board prototype designed to test the feasibility of the project. Speaker: Dr Fabrizio Ameli (INFN Roma La Sapienza) • 11:20 Wet mateable optical connector advancements 20m Over the past few years fibre optic connector technology has made significant advancements especially within the underwater matable field. This presentation list some of the enhancements and experiences gained. Speaker: Mr Steven Thumbeck (SEACON Advance products LLC) • 11:40 The electro-optical cabling system for the NEMO Phase-2 tower 15m The cable system layout for the NEMO Phase-2 project has been studied starting from the experience obtained after NEMO Phase-1 deployment. The aim has been to improve the reliability and simplify the integration procedures of the system. This has been attained by reducing the number of optical fibers in the backbone and by an improved layout of the optical links in the cabling. Moreover an optimization in order to reduce the cost, in view of a large scale industrial production, has been performed. The design characteristics of the cabling system proposed for the detector line are presented. Speaker: Dr Antonio D'Amico (INFN-LNS) • 11:55 KM3NET deep sea wet mateable connector: report of performed tasks and results 10m main talk chapters: - short description of the wet mateable connectors concept and main features - report about the activity of design, prototyping and tests made by INFN Genoa mechanical design department and internal shop - Description of first prototype tests (currently ongoing) - First preliminary test results - Performed tasks - Future activity - possible industry collaborations Speaker: Dr Diego Torazza (I.N.F.N. Genova) • 12:05 The sector of the Antares line to be deployed in the NEMO site 10m The NEWASTR project consists in the realization and deployment of an Antares mini string in the NEMO’s Capo Passero site together with the NEMO tower. This project has been proposed to make an on-site comparison between the two different layouts and to check how the bioluminescence phenomena can be affected by the detector geometry. In addition it will give a direct measurement of the bioluminescence activity immediately comparable to the Antares site data, since the detector is substantially the same. In this talk I will present the technical specification of the NEWASTR string and the main differences between the infrastructures used in the two sites. After that we will show the technical problems we encountered and the solutions we will use to make this project successfully work. Speaker: Dr Davide Piombo (Istituto NAzionale di Fisica Nucleare sez. Genova) • 12:15 A comparison of AC and DC power feeding systems based on the NEMO experiences 15m The NEMO Collaboration is involved in an intense activity to develop, apply and test technical solutions for an underwater laboratory with two prototypes called NEMO Phase 1 and NEMO Phase 2. In this framework both options of AC and DC power feeding systems have been explored. The design, realization, test and operation of NEMO Phase 1 AC electrical power and control system were carried out and concluded. The operational experience with this system will be reported. Presently the design and realization of the DC power system of NEMO Phase 2 is under way. Both these systems are described and compared, with a special focus on the results of NEMO Phase 1, on the tower power subsystem, and on the long term high pressure tests that have been carried out on the electric and electronics devices. Speaker: Rosanna Cocimano (INFN - LNS) • 12:30 lunch break 1h 25m • 14:00 Positioning System of the ANTARES Neutrino Telescope 15m The ANTARES neutrino telescope consists of 12 string lines containing the optical detectors. Sea water currents results on drifts for these strings of several meters from the vertical. However, muon track reconstruction is based on precise arrival of Cherenkov photons to the optical modules (~1 ns) and knowledge of the optical module position with respect to a fixed reference system with the corresponding resolution (~20 cm). The relative positioning of the detector is monitored combining two systems: an acoustic system giving the 3D-position of five hydrophones along the line and a set of tiltmeter-compasses giving the local tilt and orientation of each OM storey. With this information, a global fit of the string shape leads to the 3D-positioning of all OMs within the requirements. In this paper, the positioning system is described, and the performance and results for the first years of operation in ANTARES are shown. Speaker: Dr Miguel Ardid (IGIC- Universitat Politècnica de València) • 14:15 Acoustic tomography applied to the Baikal Neutrino Telescope 15m An acoustic echo-location system was applied for distant localization of the Baikal Neutrino Telescope string positions. The echo-location system was situated on the ice surface, while the telescope stayed in its standard arrangement between 1100 and 1200 m depth. "Large" reflectors, such as the end buoys located above the strings, served as reference marks. Acoustic localization of these marks was conducted by means of antenna comprising four acoustic projectors spaced with 50 meters from each other and placed under the ice on the depth of 9.5 m. Acoustic pulses occupied the frequency band between 10 and 22 kHz and had the length of 51.2 s. In result of tomographying, all three large objects (two double buoys and the central electronics module) were localized and visualized as evident (contrast) spots. Localization accuracy represented the value of app. 0.2 m (range lengthwise) and app. 1.0 m (range crosswise), which was fully acceptable for current purposes. There also have been made estimations for signal forms and parameters necessary for improved acoustic tomography measurements of the telescope. Speaker: O Kebkal (Evologics GmbH, Berlin, Germany) • 14:30 The acoustic positioning system for NEMO Phase 2 15m The acoustic positioning system is one of the key subsystems of an underwater neutrino telescope. Both in Antares and in NEMO-phase 1 the acoustic positioning system was based on “off-the-shelf” commercial technology. This technology is typically based on the use of acoustic beacons, displaced to form a Long Baseline (LBL) on the sea bed, and acoustic receivers (hydrophones) mounted on the structure, to monitor the movements of photomultipliers (PMTs) in water. The hydrophone signals are processed independently from the rest of the detector signals and used only for acoustic positioning. Thanks to the syncronous and phased data transmission/acquisition protocols developed by the NEMO Collaboration, already tested in the NEMO Phase 1 experiment, an innovative DAQ system for acoustic signals is now under realization for the NEMO Phase 2 experiment. On the NEMO Phase 2 tower, we will install 34 hydrophones (two per each floor plus two in the tower base). All hydrophone signals will be sampled underwater at 192 kHz and 24 bit resolution, and continuolsy sent to shore. Acoustic data samples will be tagged with the absolute GPS clock information of the detector, used to tag the PMT data, that has a precision of about 1 ns. On shore, acoustic data will be distributed to the PC farm for acoustic positioning analysis and to PC farm for the acoustic background monitoring. The latter will permit the first studies for acoustic neutrino detection and interdisciplinary studies. Speaker: Dr Francesco Simeone (Physics Department University "Sapienza" and INFN,Roma) • 14:45 NURC expertise for Neutrino Telescope 15m NURC, the NATO Research Centre in La Spezia (ITALY) has been working for almost 50 years in the domain of underwater technology. This paper will describe NURC capability in the underwater acoustics technology and how this can be applied to the Neutrino telescope in Mediterranean Sea. Expertise will be described in deep water hydrophones design, acoustic and oceanographic calibration for deep water sensors, data acquisition and telemetry, acoustic positioning system, data tracking as well as importantly huge experience in systems design. In addition, NURC will present examples of some experimentations that were carried at sea by the Centre since 50 years and that take benefit of the full year availability of their two own ships ALLIANCE and LEONARDO. Eventually, NURC will present the work that it is currently doing with the Italian company SMID on the delivery of fully calibrated deep water hydrophones especially designed and built for the monitoring of neutrinos within the NEMO project for the Istituto Nationale di Fisica Nucleare (INFN) in Catania Italy. Speaker: Dr Alain Maguer (NURC - Nato Undersea Research Centre) • 15:00 On line monitoring of the power control and engineering parameters systems of the NEMO Phase-2 tower. 15m The NEMO Collaboration is presently carrying out an intense activity on “NEMO Phase-2” project for the realization of a 16 floor tower. In this paper the design of the electrical power control system and of a system for the monitoring of some engineering parameters, like depth, floor orientation and attitude and acceleration, are presented. The proposed architecture is strongly modular and flexible. The entire architecture is described with a special focus on the electrical parameters display and protection system and on the sensors fusion algorithm implemented to obtain the attitude through MEMS accelerometers and magnetometers sensors. Speaker: Dr Angelo Orlando (INFN - LNS) • 15:15 Time calibration and positioning for KM3NeT 15m In this contribution we review the concepts put forward for the time calibration and positioning systems of the future KM3NeT neutrino telescope in the Mediterranean Sea. Even though the final layout of the detector, its mechanical structures and the light detection technologies to be used are not yet defined, much progress has been made in clarifying the possible technologies available for calibration and positioning. Concerning time calibration, we review the different concepts proposed, namely Optical Beacons (LED and Laser), fibres or copper cables, K40, and an internal clock signal. For positioning, in order to deal with longer distances and keep the cost under control the use of acoustic signals with lower frequency components in combination with cheaper hydrophones is being investigated. The need and use of compasses and tiltmeters is strongly correlated to the mechanical structure chosen. For absolute positioning, three methods are being considered: acoustics from navigation, a sea surface array for shower coincidences and the shadowing of the moon. We will summarize the advantages and drawbacks of each proposed solution and their suitability depending on the different detector schemes. Speaker: Dr Simona Toscano (IFIC - Valencia) • 15:30 Time Calibration of the NEMO apparatus 15m This presentation will describe the time calibration system proposed for the NEMO (NEutrino Mediterranean Observatory) underwater neutrino telescope. The time calibration is a very critical task to perform in such a large apparatus, as its track reconstruction capabilities strongly depend on the accuracy of the time alignment of the measurements made by the different sensors. In the prototype apparatus of NEMO Phase 1, which was deployed at a test site off the coast of Sicily, at 2000 m depth, in December 2006, a system based on an optical fibre network which distributed calibration signals from fast optical pulsers to groups of photomultipliers was used. A similar approach, but now based on a network of copper cables, is under development for the NEMO Phase 2 test apparatus, which is planned to be installed at 3500 m depth. Both calibration systems are controlled from an onshore console, which also delivers GPS-syncronized clock signals to the whole apparatus. We will illustrate the performance of the time calibration system of NEMO Phase 1, comparing the results from the laboratory tests before deployment to the measurements made in situ, and we will then illustrate the new system under implementation for NEMO Phase 2. The possible implications toward the design of a km3 apparatus will be also discussed. Speaker: Dr Marco Circella (INFN Bari) • 15:45 Calibration from ten to hundreds of meters in an underwater neutrino telescope 15m A critical review of the available calibration techniques will be given. We will discuss the effect of the optical properties of water on different candidate light sources and the difficulties from an engineering and electronics point of view. The merits of candidate light sources will be compared Speaker: Mr Spyridon Koutsoukos (NOA / Nestor) • 08:30 16:00 Parallel session on Physics Salle Raimu-A ### Salle Raimu-A #### Palais Neptune Conference Center, Toulon Palais des Congrès Neptune Place de Besagne Centre Commercial Mayol • 08:30 Results from the NEMO Phase1 experiment 20m The NEMO collaboration, in order to validate the technologies for the future km3-scale underwater neutrino detector, realized a technological demonstrator, called “NEMO Phase-1”. In December 2006 it was deployed at the NEMO Test-Site (2000 m depth, 25 km offshore Catania). The demonstrator includes prototypes of the critical elements of the proposed km3-scale detector: a small-scale tower called mini-Tower and a Junction Box. Results from the NEMO mini-Tower are presented. Positions of the optical sensors in the mini-Tower are reconstructed through the acoustic position system and compared with the environmental sensors data. First atmospheric muon tracks have been reconstructed and compared with Montecarlo simulations. Speaker: Dr Isabella Amore (INFN-LNS) • 08:50 ANTARES time calibration 20m The ANTARES collaboration has almost completed the construction of an underwater neutrino telescope located at 2500 km depth, 40 km away from the Toulon coast in France. The final detector will consist of 900 photomultipliers (PMTs) distributed in 12 lines. At present, the deployed detector is the largest neutrino telescope in the northern hemisphere. The aim of ANTARES is the detection of cosmic neutrinos. A good angular resolution, which relies on a good time resolution and positioning, is required to identify the neutrino sources. In this contribution, we review the ANTARES time calibration systems, namely: 1) the on-shore dark room calibration, which allows the measurement of the relative time offsets between PMTs, 2) the echo-based clock system, which enables the measurement of the time delay of the signal from the clock board located on each storey to the shore station, 3) the optical beacons which send light pulses that allow the relative time calibration of PMTs, and 4) the K40 calibration which together with the OBs allow a determination of time differences between PMTs of the same storey. These systems have shown that the required time resolution is achieved. Moreover, they ensure that the relative time offsets between PMTs are properly computed, and therefore enable an optimized track reconstruction. The experience gained with ANTARES in the issue of time calibration is of great value in the design of the corresponding system for a VLVNT in the Mediterranean Sea. Speaker: Mr Francisco Salesa (IFIC-Valencia) • 09:10 Atmospheric muons in the ANTARES detector 20m The Antares detector was operated in a configuration with 5 lines for a period of 10 months from Feb 2007 until Nov 2007. The duty cycle was better than 80%. During this period almost 2 10^7 atmospheric muon triggers were collected. This large sample was used to test Monte Carlo simulation programs and to evaluate possible systematic effects due to uncertainties on environmental parameters and detector description. First results are presented and discussed. Speaker: Annarita Margiotta (Sezione INFN and Universita' Bologna) • 09:30 Monte Carlo simulation studies of the timing calibration accuracy required by the NEMO underwater neutrino telescope 20m The results of Monte Carlo simulation studies of the timing calibration accuracy required by the NEMO underwater neutrino telescope are presented. The NEMO Collaboration is conducting a long term R&D activity toward the installation of a km3 apparatus in the Mediterranean Sea. An optimal site has been found and characterized at 3500 m depth off the Sicilian coast. Monte Carlo simulation shows that the angular resolution of the telescope remains approximately unchanged if the offset errors of timing calibration are less than 1 ns. This value is tolerable because the apparatus performance is not significantly changed when such inaccuracies are added to the other sources of error (e.g., the accuracy position of optical modules). We also discuss about the optical background rate effect on the angular resolution of the apparatus. Speaker: Dr Rosario Megna (INFN Bari) • 09:50 Reconstruction of hadronic cascades in large-scale neutrino telescopes 20m In order to achieve optimal angular resolution in searchers for neutrino point sources, neutrino telescopes are optimised for the detection and reconstruction of muon tracks, thus concentrating on muon-(anti)neutrino charged-current reactions. However, the efficiency for detecting neutrinos can be improved significantly by investigating also reaction channels containing a hadronic and/or electromagnetic particle cascade ("shower") in their final states, but no muon; these channels in particular comprise electron (anti)neutrino charged-current reactions and neutral-current reactions of all neutrino flavours. Although the angular resolution for shower events cannot compete with that of muon events, an optimal reconstruction of showers will contribute valuable information, especially when it comes to measuring the neutrino energy. A strategy that allows for the reconstruction of direction and energy of hadronic cascades will be presented, as well as preliminary results from simulation studies of the ANTARES twelve-string detector. The analysis techniques are of very generic nature and can thus easily be applied for large-scale neutrino telescopes, such as KM3NeT. Speaker: R Auer (Erlangen Centre for Astroparticle Physics) • 10:10 Study of the calibration potential of HELYCON detectors with ANTARES 20m The "HEllenic LYceum Cosmic Observatories Network" (HELYCON) collaboration is constructing a network of detector stations dedicated to the study of Extensive Air Showers. The use of HELYCON detectors is also envisaged for the calibration of a cubic kilometer scale Mediterranean neutrino telescope by means of an array of these detectors at the sea surface. The ANTARES framework is well-suited to perform a first test of the principle: a feasibility study is on-going and a test in real conditions is foreseen. In this talk the requirements for evaluating the calibration potential of a surface array in the ANTARES context are discussed. Speaker: Dr Jean-Pierre Ernenwein (Université de Haute Alsace) • 10:30 coffee break 20m • 10:50 Application of Kalman filter methods to event filtering and reconstruction for Neutrino Telescopy 20m Event reconstruction in underwater neutrino telescopes suffers from a high background noise due to theK^{40}\$ decays. Adaptive algorithms are able to suppress automatically such a noise and therefore are considered as good candidates for track fitting at the KM3NeT environment. Adaptive algorithms, based on Kalman Filter methods, are extensively used in accelerator particle physics experiments, for event filtering, track reconstruction and vertex definition. In this note we describe an iterative event filtering and track reconstruction technique, employing Kalman Filter methods and we present results from a detailed simulation study concerning the KM3NeT detector. We evaluate the accuracy of this technique and we compare its efficiency with other standard track reconstruction methods.
Speaker: Dr Apostolos Tsirigotis (Hellenic Open University)
• 11:10
Atmospheric MUons from PArametric formulas: a fast GEnerator for neutrino telescopes (MUPAGE) 20m
Atmospheric muons play an important role in underwater/ice neutrino detectors, because they provide the most abundant source of events for calibration and test. On the other side, they represent the major background source. A fast Monte Carlo generator (called MUPAGE) of bundles of atmospheric muons for underwater/ice neutrino telescopes is presented. It produces the event kinematics on the surface of a user-defined virtual cylinder, surrounding the detector. MUPAGE is based on parametric formulas obtained from a full Monte Carlo simulation of cosmic ray showers generating muons in bundle, which are propagated down to 5 km w.e. The multiplicity of the muons in the bundle, the muon spatial distribution and energy spectrum are simulated according to a specific model of primary cosmic ray flux, with constraints from measurements of the muon flux with underground experiments. As an example of the application, the result of the generation of events on a cylindrical surface of 3 km^2 at a depth of 2450 m of water is presented.
Speaker: Prof. Maurizio Spurio (University of Bologna)
• 11:30
KM3NeT: optimization studies for a km3 neutrino detector 20m
The KM3NeT collaboration is approaching the phase of definition of a technical project for a high energy neutrino telescope to be installed in the Mediterranean sea. In this phase MonteCarlo simulations can give constraints on some important parameters for a technical design of the detector. In this contribution the performance of a detector made of tree-dimensional structures hosting the optical modules will be compared aiming at the optimization of some parameters of the detector layout. The ANTARES software modified for a km3 detector is used. In particular, in case of structures based on bars the optimization of the bar length, and the performance of detectors equipped with optical modules with different characteristics (quantum efficiency, directionality….) will be shown.
Speaker: Dr Rosa Coniglione (INFN-Laboratori Nazionali del Sud)
• 11:50
Study of the angular acceptance of a km3 telescope in the Mediterranean Sea 20m
The KM3NeT collaboration aims to realize in the Mediterranean Sea a high energy neutrino telescope that will be optimized for muon neutrinos in the energy range between 1 TeV and 1 PeV. From 1 TeV to several tens of TeV only up-going neutrinos can be unambiguously identified due to the overwhelming presence of the atmospheric muons. However, at energies larger than 100 TeV, neutrinos are absorbed by the Earth, while the atmospheric flux vanishes, therefore the most energetic neutrinos can be detected only above the horizon. Moreover, the reconstruction accuracy for atmospheric muons affects the rejection capability, thus minimizing the percentage of muons mis-reconstructed as up-going, but also the detection of the moon shadow that represents an important reference for the absolute pointing of the telescope. In this frame, the PMT orientation represent a crucial issue. In this contribution, the influence of the PMT orientation, for a km3 detector made of 10” PMTs, is investigated.
Speaker: Piera Sapienza (INFN-LNS)
• 12:10
MC studies of the KM3NeT physics performance 20m
KM3NeT neutrino telescope configurations with different detector components and geometry have been simulated and studied with modified ANTARES software. The physics performance of KM3NeT will be characterised by two parameters: neutrino effective area and angular resolution of the reconstructed muons. These two benchmark parameters are determined and compared for the different simulated KM3NeT options. The advantages and disadvantages of various neutrino telescope configurations will be discussed, together with the latest studies of sensitivity of these configurations to the cosmic neutrino fluxes.
Speaker: Dr Rezo Shanidze (ECAP/University of Erlangen)
• 12:30
Software frameworks for KM3NeT 20m
Large-scale experiments like KM3NeT require an immense amount of collaborative work to create and maintain their analysis software. The complete chain of reconstruction tools has to be modular and adhere to a pre-defined data flow. Additionally, the source code must be modular to ease its development and maintenance. A software set-up implementing these points does not only allow a large group of experts to cooperate in creating a functional piece of software but also helps the individual user to scrutinise the results obtained with it. Such program modularisation and the definition of a corresponding data flow are the essential elements provided by a "software framework". The presentation will introduce the basic concepts of software frameworks and in particular present "IceTray", the framework currently used by the IceCube collaboration. It is especially suitable for KM3NeT, as it was written with applicability for a neutrino detector in mind. IceTray has been evaluated and adapted for the ANTARES environment to demonstrate its suitability for KM3NeT. The customisations that were made during this process are presented, and an overview of new modules created during the evaluation phase is given.
Speaker: Mr Claudio Kopper (Erlangen Centre of Astroparticle Physics (ECAP), University of Erlangen, Germany)
• 12:50
First ideas for KM3Net on-shore data storage and distribution 20m
The KM3Net experiment data arrive on shore where they are processed in real time at a Data Filter Farm and are subsequently stored and backed up at a central computing centre located on site. From there we propose a system whereby the data are distributed to participating institutes equipped with large computing centres for further processing, duplication and distribution to smaller centres. The data taking site hosts the central data management services, including the database servers, bookkeeping systems and file catalogue services, the data access and file transfer systems, data quality monitoring systems and transaction monitoring daemons and is equipped with fast network connection to all large computing sites. Data and service challenges in the course of the preparatory phase must be anticipated in order to test the hardware and software components in terms of robustness and performance, scalability as well as modularity and replaceability, given the rapid evolution of the market both in terms of CPU performance and storage capacity. The role of the GRID would also have to be evaluated and the appropriate implementation selected in time for an eventual test in the context of a data challenge before the start of data taking.
Speaker: Maya Stavrianakou (NOA/NESTOR)
• 13:10
lunch break 1h 10m
• 14:20
Predictions of the Diffuse Galactic Neutrino Flux in Light of New Milagro Data 20m
Following the Milagro detection of multi-TeV gamma-rays from both the Cygnus and central Galactic regions, we investigate the consequences of a hadronic origin for this large scale diffuse emission. We demonstrate that such observations are highly relevant to the predictions of detectable fluxes by upcoming km3 neutrino-detectors. The possibility for a verification of a hadronic origin model through upcoming TeV and multi-TeV gamma-ray detectors are discussed.
Speaker: Dr Andrew Taylor (MPIK)
• 14:40
Prospects for Identifying the Sources of the Galactic Cosmic Rays with IceCube 20m
We quantitatively address whether IceCube, a kilometer-scale neutrino detector under construction at the South Pole, can observe neutrinos pointing back at the accelerators of the Galactic cosmic rays. The photon flux from candidate sources identified by the Milagro detector in a survey of the TeV sky is consistent with the flux expected from a typical cosmic-ray generating supernova remnant interacting with the interstellar medium. We show here that IceCube can provide incontrovertible evidence of cosmic-ray acceleration in these sources by detecting neutrinos. We find that the signal is optimally identified by specializing to events with energy above 40 TeV where the atmospheric neutrino background is low. We conclude that evidence for a correlation between the Milagro and IceCube sky maps should be conclusive after several years.
• 15:00
KM3NeT sensitivity to neutrino bursts from galactic supernovae 20m
A very large volume Mediterranean neutrino telescope (KM3NeT), designed and optimised for detection of Cherenkov light from interactions of neutrinos with energies above about 100 GeV, could be sensitive to an intense neutrino burst from the core collapse of a massive star in our Galaxy. In a short time interval during the burst (~10 s) the total amount of Cherenkov photons produced by low-energy (~10 MeV) neutrino interactions in the sea water rises well above the usual background level. The main source of these photons are positrons from interactions of electron anti-neutrinos with the free protons in water. The KM3NeT detector could be considered as a possible member for the SuperNova Early Warning System (SNEWS), an international network of neutrino experiments with the goal of providing an early warning of a galactic supernova. The possibilities for the detection of supernova signal with KM3NeT will be discussed in this talk.
Speaker: Dr Rezo Shanidze (ECAP/University of Erlangen)
• 15:20
Individual GRB sensitivity of the cubic-kilometre deep-sea neutrino telescope KM3NeT 20m
Gamma-ray bursts (GRB) are powerful and highly variable sources of gamma rays that indicate the existence of cosmic particle accelerators. Under the assumption of hadronic acceleration in the jet, the expected neutrino energy spectrum is derived according to the intrinsic fireball model parameters and to the observed electromagnetic data of GRBs measured with ground-based and satellite observations. Using the performance characteristics of a cubic-kilometre scale neutrino detector placed in the Mediterranean Sea, the number of events is calculated individually for all the GRBs having a known redshift visible in the southern hemisphere. The good angular resolution of this detector and the narrow time windows around the GRB detection time allow suppression of almost all the atmospheric neutrino background. From the SWIFT GRB catalogue, we have derived the mean characteristics of a burst in order to be detected as an individual point source by a cubic-kilometre detector.
Speaker: Damien Dornic (CPPM)
• 09:00 16:20
Parallel session on Photodetection Salle Raimu-B

### Salle Raimu-B

#### Palais Neptune Conference Center, Toulon

Palais des Congrès Neptune Place de Besagne Centre Commercial Mayol
• 09:00
Photomultipliers from ET Enterprises Ltd (formerly Electron Tubes Ltd) 30m
ET Enterprises Limited is a new UK company which has taken over manufacture and supply of the Electron Tubes brand photomultipliers and associated hardware to meet the needs of detector users in industry and research around the world. Although a new company, its history goes back to the 1930s when, as part of EMI, it first became involved with light detection technologies and the development and manufacture of photomultipliers which started in the late 1940s. We were one of the first companies to produce a hemi-spherical photomultiplier, which was a 5 inch pmt for the SNO project. This was followed by the first major order for 8 inch hemi-spherical pmts for the BOREXINO project. Then came our biggest order ever for pmts, which was for the BaBar DIRC detector. Our development efforts have also been directed towards rugged pmts for space applications, such as the GRO, SOHO, HIPPARCOS, and INTEGRAL projects. In parallel with this we developed and introduced a range of extremely rugged, high temperature pmts for oil exploration applications. In the Astro-Physics sector we were the first company to develop and introduce a small hemi-spherical photomultiplier for the high-resolution camera of the MAGIC cosmic shower telescope. We have also developed a range of ultra-low background pmts for Dark Matter experiments, including pmts for operation at liquid argon temperatures. Current projects are DAMA, WARP and ICARUS.
Speaker: Mr Ronald Stubberfield (ET Enterprises)
• 09:30
Recent Progress in Hamamatsu Large Format PMTs 30m
Recent activities for large format PMTs in Hamamatsu are shown. First topic is the development of 12 inch PMT. Hamamatsu decided to develop 12 inch PMT for the use of neutrino experiments. As you know, several large-scale neutrino experiments are being considered right now. We would like to offer 12 inch PMT as one of options. Second topic is High QE photocathode. Hamamatsu succeeded to make High QE bialkali photocathode. Available products are still limited, but we are trying to apply this technology to large format PMTs. The latest result is shown. A 13 inch HPD, Hybrid Photo Detector, is being developed right now. This photo detector is made by the combination with solid-state devices and vacuum tube technology. This detector could be also one of options for future neutrino experiments.
Speaker: Mr Yuji Yoshizawa (Hamamatsu Photonics)
• 10:00
Title: The X-HPD -- A modern Implementation of a SMART Concept 30m
The concept of hybrid photodetectors which combine a large area photocathode with a crystal scintillator anode in the centre of a hemispherical vacuum tube was demonstrated first with the Philips SMART tubes and, more recently, with the QUASAR tubes of the Lake Baikal experiment. Photoelectrons from the cathode are accelerated by a potential difference of 20-30 kV and deposit their kinetic energy in the scintillator / Phosphor. The generated scintillation light is detected by a small and low cost photodetector, e.g. a conventional PMT. The X-HPD study is a variation of this concept aiming at improved performance and maximum simplicity. The glass envelope is essentially spherical and a spatial scintillator crystal is mounted in its centre. The spherical symmetry leads to a uniform collection efficiency and very small intrinsic time spread over the full viewing angle of 120˚ (3 pi solid angle). The amplification mechanism by means of the scintillator leads to a distinct single electron response and limited photon counting capability. A welcome side effect is the double-cathode phenomenon. Light traversing the photocathode without conversion has a second chance to be detected on the opposite side, resulting in almost double quantum efficiency. We report about test results of a first X-HPD of 208 mm diameter with a cylindrical LYSO crystal. A second tube with improved electrostatical properties is in prepration at CERN and will be tested in the coming weeks.
Speaker: Dr Christian Joram (CERN / PH Department)
• 10:30
coffe break 30m
• 11:00
Crystal-based hybrid single photon detector development for the KM3NeT cubic kilometre neutrino telescope 30m
Scintillating crystal-based hybrid photon detectors have been demonstrated as viable single photon detectors since 1996 in the Lake Baikal neutrino telescope. Prior to this, the Philips XP2600 'SMART' X-HPD had been developed under the DUMAND program, while more recently, developments at CERN have demonstrated the advantages of a true concentric geometry with a scintillator at the geometric centre of a spherical photocathode, giving almost 100% electrostatic collection efficiency over a ~ 3*pi solid angle coverage. Under a collaboration within the Groupement d'Intêret Scientifique cooperation signed between Photonis S.A. and the IN2P3 (Institut National de Physique Nucléaire et de Physique des Particules) division of the CNRS, a series of quasi-spherical X-HPDs will be developed with sizes ranging between 8" and the maximum that can be constructed for fitting in a standard 17" optical pressure sphere for use in a deep sea neutrino telescope. The thrust of this R&D will be to investigate the industrialisation of the X-HPD to the point where it represents a significant cost reduction per cubic kilometre of instrumented volume compared to conventional PMTs, thereby allowing for extremely large telescope target volumes. Such gains will arise from industrialisation of an all-glass envelope construction, the internal deposition of enhanced efficiency bi-alkali photocathodes, and either from cost reductions in the central scintillating crystal or the use of a deposited phosphor.
Speaker: G Hallewell (Centre de Physique des Particules de Marseille)
• 11:30
Hybrid Phototubes in Neutrino Telescope: Experience and Perspectives 30m
The advent of the first generation of neutrino telescopes gave impetus to the development of hybrid phototubes with luminescent screens. The phototubes have been used in the two pioneering neutrino telescope projects - Deep Underwater Muon and Neutrino Detector (DUMAND) in the Pacific Ocean and the Lake Baikal neutrino experiment. In this paper we summarize a wealth of experience accumulated in a time of the development of the phototubes and operation of arrays using the phototubes as basic detecting elements. Extensive experimental data on the phototubes (sensitivity, time and amplitude resolutions, dark current, stability etc) are presented. Some technological problems encountered, solved and still existing, are discussed. It is shown that even with existing technologies the phototubes are the most adequate photodetectors for large scale deep underwater neutrino telescopes. Some issues concerned with future developments of the phototubes (technological improvements, optimization and improvement of the phototube performance etc) based on our present day knowledge are discussed too.
Speaker: Dr Bayarto Lubsandorzhiev (Institute for Nuclear Research of RAS)
• 12:00
A hybrid photodetector using the TIMEPIX pixel semiconductor for photoelectron detection 30m
A new concept of a hybrid photodetector is presented. It consists of a standard photocathode combined with the TIMEPIX semiconductor detector. The photoelectron is accelerated in a field of 10 to 20 keV to the silicon sensor of the TIMEPIX. The photoelectron generates electron-hole pairs in the silicon which are directed to the pixel electronics of the TIMEPIX ASIC. This charge signal is compared to a threshold and accordingly starts the counting of clock pulses until the end of a frame time. The TIMEPIX contains 65000 parallel working pixels of 55 microns pixel pitch. This hybrid photodetector enables the time measurements of each single photoelectron and gives a direct digital output of this information.
Speaker: Prof. Gisela Anton (Erlangen Centre for Astroparticle Physics)
• 12:30
lunch break 1h 30m
• 14:00
Sensitivity of a multi-photomultiplier optical module for KM3NeT 30m
For the KM3NeT neutrino telescope an optical module with a number of small phototubes (multi-PMT optical module) will be advantageous for various reasons, e.g. reduced background rate, a larger number of coincidence hits and ultra-high neutrinos can be detected. The properties of such a design have been investigated by measurements and simulations. Several types of 3” PMT were exposed to LED light pulses with intensities down to the single-photon level. A small transit time spread was found for the 10-stage XP53B2 tube which is therefore proposed for the KM3NeT setup. At the same time an excellent peak-to-valley ratio of 3.9 was observed. The simulation tool Sirène for a photo-sensor based neutrino telescope has been applied to allow a comparison with the ANTARES detector. With a coverage of almost 4*pi sr, all muon directions can be observed with an improved identification and rejection of atmospheric muons. Although the symmetric angular coverage results in a smaller fraction of the photocathode area detecting up-going neutrinos, the superior quantum efficiency available for 3" PMT compensates for this effect. Cherenkov photons produced by muons as well as photons from electromagnetic showers arrive close in time and are well suited for track reconstruction. For up-going neutrinos and down-going muons the multi-PMT arrangement shows a better performance in both the photo-electron response and in the number-of-hits response as compared to the present ANTARES design.
Speaker: Prof. Herbert Loehner (KVI, University of Groningen)
• 14:30
Instrumentation of A New Direction Sensitive Segmented Optical Module. 15m
An efficiency increase in the intermediate energy region for an underwater neutrino telescope could be an important development to gain a better sensitivity in the study of the physical processes concerning the deep universe and to have a useful tool for better detector calibration with atmospheric neutrinos. A new, direction sensitive, segmented optical module is under development in Genova: according to preliminary simulations, this kind of device can, together with a dedicated reconstruction strategy, improve by a significant factor the telescope sensitivity at low and intermediate energies. This optical module will feature a newly developed 10" Hamamatsu 4-anodic PMT coupled to a dedicated electronic to be integrated in the NEMO readout chain: the first directional OMs will be installed in the NEMO test site during the preliminary phase of the experiment.
Speaker: Dr Andrea Bersani (INFN Genova)
• 14:45
Characterization of a prototype of a new multianodic large area photomultiplier 15m
A prototype of a new large area (10”) 4-anodic photomultiplier, manufactured by Hamamatsu for the NEMO collaboration, will be used for the first time for the construction of a Km3 scale neutrino underwater telescope, in the KM3NeT framework. Using testing facility realized in our laboratory, we have performed tests on prototype performances at room temperature, atmospheric pressure and different light conditions. The response of the phototube has been measured for each anode separately. We report the dark count rate measures and the time and the charge characteristics of the photomultiplier when the whole photocatode surface is fully illuminated, as Transit Time Spread, Peak To Valley ratio, charge resolution, linearity and gain. We measured also the fraction of spurious pulses, as PrePulse, DelayPulse an AfterPulse of type 1 and 2, according to Hamamatsu definitions. Photomultiplier characteristics have been studied also by scanning the photocatode area with a single-photon pulsed beam with 5 mm diameter on PMT surface.
Speaker: Dr Emanuele Leonora (INFN CATANIA)
• 15:00
LED based powerful nanosecond light sources for calibration systems of deep underwater neutrino telescopes 20m
Powerful nanosecond light sources based on LEDs have been developed for use in calibration systems of deep underwater neutrino experiments. The designs of such sources are described. The light sources use either matrixes of ultra bright blue InGaN LEDs or a new generation of high power blue LEDs. The drivers of such LEDs may be implemented of avalanche transistors or a complementary pair of fast RF transistors. The most powerful and fast light sources utilize two or three consecutive avalanche transistors. It is shown that such light sources have light yields of up to 10**11-10**12 photons per pulse with a few nanosecond width of light pulses. The results of extensive studies of light emission kinetics of currently existing ultra bright LEDs are presented. It is shown that the light sources are very stable, reliable and robust. They are easily constructed and operated and very useful not only in calibration system but in laboratory test measurements of photodetctors.
Speaker: Bayarto Lubsandorzhiev ((Institute for Nuclear Research of RAS))
• 15:20
Distribution of bioluminescence in the Mediterranean Sea and predicted effects on a neutrino telescope 30m
The density of bioluminescent organisms was measured in the eastern and western Mediterranean, from the subsurface layer to the seafloor; in the Ligurian, Tyrrhenian, Ionian, Adriatic Seas and the Straits of Sicily, including neutrino telescopes sites at ANTARES and NESTOR. Bioluminescence decreased with depth at different rates at the different sites. At depths 500-1500m, the Adriatic was found to have the highest mean density (2.5 m-3), and the eastern Ionian Sea (NESTOR) to have the lowest (0.3 m-3), while the Strait of Sicily, the Tyrrhenian, the western Ionian and the Ligurian (ANTARES) Seas showed very similar values of 1.38, 1.53,1.53 and 1.65 m-3 respectively. Deeper within the water column (1500-2500m), the strait of Sicily and the Ligurian Sea were found to have the highest densities (0.74 and 0.62 m-3), and the Ionian sites to have the lowest; 0.21 m-3 in the western and 0.06 in the eastern sectors. Modelling encounter of bioluminescent organisms carried in deep sea currents impinging on a telescope photodetector predicts bioluminescent flashes, 16.59 h-1 at ANTARES and at NESTOR 1.84 h-1 at 1500-2500m depth, 1.16 h-1 at 2500-3500m and 0.49 h-1 at >3500m.
Speaker: Ms Jessica Craig (Oceanlab , University of Aberdeen)
• 15:50
coffee break 10m
• 16:30 19:00
Visit to ANTARES infrastructures 2h 30m

Transfer by boat from Toulon harbour, leaving at 16:30!

• Thursday, 24 April
• 09:00 17:30
Plenary Session II Salle Colbert

### Salle Colbert

#### Palais Neptune Conference Center, Toulon

Palais des Congrès Neptune Place de Besagne Centre Commercial Mayol

Chairs: Gerard van der Steenhoven (NIKHEF): Morning session, John Carr (CPPM): Afternoon session

• 09:00
Commissioning the IceCube neutrino telescope at the South Pole 30m
Following up on the success of the AMANDA detector, the IceCube experiment is building the first of the next generation, cubic kilometer neutrino telescopes at the South Pole. This effort is now half way towards completion. This talk will focus on the technical aspects of the project: namely, the construction, the commissioning, and the technical data analysis work that has been and is underway to built the detector. Moveover, technical results will be presented which demonstrate that the detector has been collecting high quality, physics ready data for the last two years.
Speaker: Brendan FOX (Pennsylvania State University)
• 09:30
The prototype string for the km3 scale Baikal neutrino telescope 20m
A full-scale prototype string for the future km3-scale neutrino telescope has been deployed in April, 2008 and is fully intergrated into the NT200+ telescope. All basic string elements - optical modules, 200MHz FADC readout and calibration system - have been redesigned following experience with NT200+. First results of in-situ operation of this prototype string are presented.
• 09:50
Perspectives for High Energy Neutrino Astronomy 30m
In this talk I'll present theoretical predictions of the diffuse neutrino fluxes constrained by the cosmic ray and gamma-ray data. Also I'll review possible classes of the point-like high energy neutrino sources and discuss perspectives of their detection.
Speaker: Dmitri SEMIKOZ (APC Paris)
• 10:20
The European Research Fleets 30m
Installation and maintenance of Subsea observatories and very large telescopes require access to workhorse marine vessels and underwater systems. The cost of possession of such infrastructures is highly dependent to their rate of usage. Such rate of usage could be optimised by the multipurpose use of the infrastructure, or by full rate of usage. Other possibilities are Bartering, chartering schemes or sharing of the investments and running costs between several partners and users. Its also possible to use opportunities within industrial fleets, through tenders processes. However, availability of the systems, specificities and complexities of the tasks required high level of services and access to trained and experimented teams. In the presentation we will set-up the situation of the European research fleets within green, blue books, OFEG, Marine Board, Eurofleet and ESFRI contexts. A survey of existing systems (ships and underwater systems), and access in an optimal way would be addressed. The presentation will emphasis new views toward common strategy and enhanced uses of European Ocean research Fleets. The description of the existing fleets and their management, and the evolution over the next decades would be addressed, and the inventory of large exchangeable instruments will open a discussion on the possible exploitation schemes for future maintenance and installation of underwater observatories.
Speaker: Vincent RIGAUD (IFREMER, Centre de Brest, France)
• 10:50
Coffee break 20m
• 11:10
Experience in ESONET NoE and Standardisation issues for undersea observatories 30m
ESONET is a Multidisciplinary European Network of Excellence (NoE) associating 50 partners from 14 countries and more than 300 scientists and engineers and dedicated to the lasting integration of research and development in deep sea observatories in Europe. Amongst other actions, it works at establishing seafloor infrastructure that will provide platforms for instrumentation deployed throughout the water column and the geosphere below in a standard manner. Those platforms will provide power for instruments and real-time two-way data communications. This preparatory phase of observatories implementation is intending to select the most suitable standards in order to develop observatories interoperable between themselves and that would be able to benefit of the common sharing facilities. After the Esonet Best Practices workshop held in Bremen at the end of January 2008, the state of art has been made and some groups working on key standardization topics have been constituted to manage standardization plans. Amongst those plans the data management plan and the sharing facilities plan will be presented. Those plans will be implemented and tested in the four so called Esonet Demonstration Missions. Then technical aspects regarding sensors connexion and junction boxes will be briefly discussed.
Speaker: Ingrid PUILLAT (IFREMER Centre de Brest, France)
• 11:40
Communications and Power for undersea Neutrino Telescopes 20m
Speaker: Ronan MICHEL (Alcatel-Lucent Submarine Networks)
• 12:00
Underwater matable electro-optical connectors: the feedback from Antares 20m
ABSTRACT: In the Antares detector the link between the Junction Box and each of the line anchors is made by a cable (2 electrical conductors + 4 monomode optical fibers) equipped at both ends by a pair of underwater matable connector. The connection is performed by a ROV. I will summarize the experience gained in Antares with this key equipment.
Speaker: Pascal VERNIN (CEA Saclay, Paris)
• 12:20
lunch break 1h 40m
• 14:00
Deep Sea Acoustic Neutrino Detection and the AMADEUS System as a multi-purpose acoustic array 20m
The use of conventional neutrino telescope methods and technology for detecting neutrinos with ultra-high energies from astrophysical sources would be prohibitively expensive and may turn out to be technically not feasable. Acoustic detection is a promising option for future deep-sea neutrino telescopes operating in this energy regime. It utilises the effect that a cascade evolving from a neutrino interaction in water generates a coherently emitted sound wave with frequency components in the range between 1 and 50 kHz. The AMADEUS (Antares Modules for Acoustic DEtection Under the Sea) project is integrated into the ANTARES neutrino telescope and aims at the investigation of techniques for acoustic particle detection in sea water. The acoustic sensors of AMADEUS are using piezo elements and are recording a broad-band signal with frequencies ranging up to 125 kHz. After an introduction into acoustic neutrino detection it will be shown how an acoustic array similar to AMADEUS could be used for positioning as well as marine research and acoustic particle detection. Experience from AMADEUS and possibilities for a future large scale neutrino telescope in the Mediterranean Sea will be discussed.
Speaker: Robert LAHMANN (University of Erlangen)
• 14:20
Biological Sonar and Noise Pollution 30m
Noise pollution in the marine environment is an emerging but serious concern. Its implications are less well understood than other global threats and largely undetectable to everyone but the specialist. In addition, the assessment of the acoustic impact of artificial sounds in the sea is not a trivial task, certainly because there is a lack of information on how the marine organisms process and analyze sounds and how relevant these sounds are for the balance and development of the populations. Further, this possible acoustic impact not only concerns the hearing systems but may also affect other sensory or systemic levels and result equally lethal for the animal concerned. If we add that the negative consequences of a short or long term exposure to artificial sounds may not be immediately observed one can understood how challenging it is to obtain objective data allowing an efficient control of the introduction of anthropogenic sound in the sea. To answer some of these questions, the choice to investigate cetaceans and their adaptation to an aquatic environment is not fortuitous. Cetaceans, because of their optimum use of sound as an ad-hoc source of energy and their almost exclusive dependence on acoustic information, represent not only the best bio-indicator of the effects of noise pollution in the marine environment, but also a source of data to improve and develop human underwater acoustic technology. Here, we present how the characteristics and performance of the sperm wh
Speaker: Michel ANDRE (Laboratori d'Aplicacions Bioacústiques (LAB), Universitat Politècnica de Catalunya (UPC))
• 14:50
Coincidences between Gravitational Wave Interferometers and High Energy Neutrino Telescopes 30m
Both gravitational waves (GW) sources and high energy (HE) neutrino emitters involve compact objects and matter moving at relativistic speeds. Moreover, GW emission requires departure from spherical symmetry, which is the case if clumps of matter are accreted around black holes, and blobs of plasma are ejected in astrophysical jets, where HE neutrinos are believed to be produced. Both messengers do not interact with surrounding matter, hence pointing directly to the heart of the engines that power those emissions. Time coincidences between GW interferometers and HE neutrino telescopes would then give a unique insight on the physics of the most powerful objects in the Universe. Those coincidences in time require GW bursts (signals localized in time), and would give the possibility for GW antennae to confirm a burst detection, and for neutrino telescopes to sign the non-atmospheric origin of an upward-going muon. Some informations related to Quantum Gravity models could also be extracted. This talk will try to demonstrate that such coincidences are: - possible : sources of both GW and HE neutrinos, able to emit signals coincident in time, exist in our Galaxy; - observable : the visibility sky maps of e.g. Virgo and Antares are not orthogonal; - detectable : the resulting coincidence probability for a fixed accidental coincidence rate in a given time window (e.g. 1/yr and dt = 1s), constraining the authorized background level for each individual detector, is not negligible.
• 15:20
Alert systems for Gamma Ray Bursts 30m
GRBs are the most energetic events in the Universe, associated with the death of massive stars (core-collapse supernovae), or the merging of neutron stars or black holes. Discovered in the late 1960s, their cosmological origin was demonstrated only in 1997 when the first distance (redshift) of a GRB was measured. Theoretical models predict that the very energetic processes at work in GRBs accelerate charged particles to such energies that they could contribute to the observed high energy cosmic rays. These processes will be discussed and the observational consequences, in particular for a next generation neutrino telescopes operational in the next decade, presented.
Speaker: Stephane BASA (LAM Marseille)
• 15:50
Coffee break 20m
• 16:10
Development of Telescopes for Extremely Energetic Neutrinos 30m
Dedicated high energy neutrino telescopes based on optical Cherenkov techniques have been scanning the cosmos for about a decade. At TeV scales, limits on the diffuse flux have improved by several orders of magnitude, eliminating the most optimistic models that tend to be normalized to the extragalactic x-ray and gamma-ray backgrounds. At higher energies, neutrino telescopes have provided the first flux limits from point sources and diffusely distributed sources such as cosmogenic neutrinos generated by the GZK process. Moreover, the diffuse flux limits can be used to constrain the flux from extragalactic point sources. To substantially improve the experimental capabilities at the very highest energies, new techniques are required. I will briefly discuss several radio and acoustic-based detectors that promise to increase the sensitivity to neutrinos with energies in excess of 10^17 eV. These telescopes have already ruled out some of the more exotic predictions for neutrino intensity. In addition to flux measurements, these devices can probe for non-standard particle physics by investigating the neutrino cross-section.
Speaker: Prof. Steve BARWICK (UC Irvine)
• 16:40
Conference Summary 30m
Speaker: Emilio MIGNECO (INFN-LNS Catania)
• 17:10