Search

The KM3NeT collaboration is building a km 3 -scale neutrino telescope in the Mediterranean Sea. The current phase of construction comprises the deep-sea and onshore infrastructures at two installation sites and the installation of the first detection units for the “ARCA” (Astroparticle Research with Cosmics in the Abyss) and “ORCA” (Oscillation Research with Cosmics in the Abyss) detector. At the KM3NeT-It site, 80 km offshore Capo Passero, Italy, the first 32 detection units for the ARCA detector are being installed and at the KM3Net-Fr site, 40 km offshore Toulon, France, 7 detection units for the ORCA detector will be deployed. The second phase of KM3NeT foresees the completion of ARCA for neutrino astronomy at energies above TeV and ORCA for neutrino mass hierarchy studies at energies in the GeV range. The basic element of the KM3NeT detector is the detection unit. In the ARCA geometry, the detection unit is a 700 m long vertical structure hosting 18 optical modules. Each optical module comprises 31 3 in photomultiplier tubes, instruments to monitor environmental parameters, and the electronic boards for the digitisation of the PMT signals and the management of data acquisition. In their final configuration, both ARCA and ORCA will be composed of about 200 detection units. The first detection unit was installed at the KM3NeT-It site in December 2015. It is active and taking data since its connection to the subsea network. The time of arrival and the duration of photon hits on each of the photomultipliers is measured with a time resolution of 1 ns and transferred onshore where the measurements are processed, triggered and stored on disk. A time calibration procedure, based on data recorded with flashing LED beacons during dedicated periods, allows for time synchronisation of the signals from the optical modules at the nanosecond level. In May 2016, an additional detection unit was installed at the KM3NeT-It site. The first results with two active detection units are presented. An update of the detector status and construction is given. [ABSTRACT FROM AUTHOR]

The IceCube Neutrino Observatory is a cubic-kilometer neutrino telescope located at the geographic South Pole. Buried deep under the Antarctic ice sheet, an array of 5160 Digital Optical Modules (DOMs) is used to capture the Cherenkov light emitted by relativistic particles generated from neutrino interactions. The main goal of IceCube is the detection of astrophysical neutrinos. In 2013 the IceCube neutrino telescope discovered a high-energy diffuse flux of neutrino events with energy ranging from tens of TeV up to few PeV of cosmic origin. Meanwhile, different analyses confirm the discovery and search for possible correlations with astrophysical sources. However, the source of these neutrinos remains a mystery, since no counterparts have been identified yet. In this contribution we give an overview of the detection principles of IceCube, the most recent results, and the plans for a next-generation neutrino detector, dubbed IceCube-Gen2. [ABSTRACT FROM AUTHOR]

The IceCube detector is unique. It uses the Antarctic glacial ice as an interaction and detection medium. An array of optical sensors observes Cherenkov light from secondary charged particles resulting from neutrino interactions. The high transparency of the ice enabled the realization of a 1 km 3 large detection volume in order to detect rarely interacting particles. Neutrinos are ideal probes of the deep universe because they rarely interact with matter and propagate in straight lines. Neutrinos are thought to be produced in hadronic processes at astronomical sources such as active galactic nuclei and gamma-ray bursts. IceCube aims to detect neutrinos from such astronomical sources. IceCube recently found 28 events in an energy range approximately from 50 TeV to 1 PeV. These events are not easily explained by background derived from atmospheric origin, and therefore represent the first evidence for high energy neutrinos from an extraterrestrial origin. IceCube can also perform elementary particle physics by searching for neutrinos from SUSY particles such as neutralinos and measuring atmospheric neutrino oscillations. An overview of the latest IceCube results is provided in this paper including the 28 candidate observations and the corresponding implications. [ABSTRACT FROM AUTHOR]

Abstract: The ANTARES telescope, with a duty cycle close to unity and a full hemisphere of the sky at all the times visible, is well suited to detect neutrinos produced in astrophysical transient sources. Assuming a known neutrino production period, the background and the sensitivity can be drastically improved by selecting a narrow time window around it. GRBs, μ-quasars and AGNs are particularly attractive potential neutrino point sources since neutrinos and gamma-rays may be produced in hadronic interactions with the surrounding medium as they are the most likely sources of the observed ultra high energy cosmic rays. A strong correlation between the gamma-ray and the neutrino fluxes is expected in this scenario. ANTARES data has been analyzed in various transient source analyses with the goal of detecting cosmic neutrinos from GRBs, μ-quasars and AGNs. The sensitivity of a standard time-integrated point source search can be improved by a factor 2–3 by looking for neutrinos only during the most probable emission time. This information can be provided by the different satellite telescope types on the X-rays and γ-rays wavelengths. The results of these different analyses will be presented. [Copyright &y& Elsevier]

Abstract: The ANTARES telescope observes a full hemisphere of the sky all the time with a duty cycle close to 100%. This makes it well suited for an extensive observation of neutrinos produced in astrophysical transient sources. In the surrounding medium of blazars, i.e. active galactic nuclei with their jets pointing almost directly toward the observer, neutrinos may be produced together with gamma-rays by hadronic interactions, so a strong correlation between neutrinos and gamma-rays emissions is expected. The time variability information of the studied source can be obtained by the gamma-ray light curves measured by the LAT instrument on-board the Fermi satellite. If the expected neutrino flux observation is reduced to a narrow window around the assumed neutrino production period, the point-source sensitivity can be drastically improved. The ANTARES data collected in 2008 has been analyzed looking for neutrinos detected in the high state period of 10 bright and variable Fermi sources assuming that the neutrino emission follows the gamma-ray light curves. First results show a sensitivity improvement by a factor 2–3 with respect to a standard time-integrated point source search. The analysis has been done with an unbinned method based on the minimization of a likelihood ratio applied to data corresponding to a live time of 60 days. The width of the flaring periods ranges from 1 to 20 days. Despite the fact that the most significant studied source is compatible with background fluctuations, recently detected flares promise interesting future analyze. [Copyright &y& Elsevier]

Abstract: We review the status and results of the high energy neutrino telescopes in the Northern Hemisphere, namely ANTARES and Baikal (NT200+). After a brief introduction to Neutrino Astronomy, we describe these telescopes in their past and present configurations and report briefly on the results obtained in several areas, such as the search for high energy cosmic neutrino diffuse fluxes and point sources, the indirect search for dark matter, the multimessenger studies and the search for exotic particles, such as monopoles and nuclearites. [Copyright &y& Elsevier]

Abstract: The construction of IceCube neutrino telescope and IceTop surface array was successfully completed at the South Pole during December, 2010. IceCube is the most sensitive telescope to date for observing high energy neutrino sources. The performance of the IceCube detector and a summary of results will be reported from earlier years as the detector increased in size from 40, 59 and 79 strings. New analysis methods developed for the study of the Southern Hemisphere as well as for the extended regions in the sky will be emphasized. The long term experience with AMANDA and IceCube has proven that the South Pole ice is an ideal site for astroparticle physics. New ideas and possible future projects beyond IceCube will also be presented. [Copyright &y& Elsevier]

Abstract: The operation of large underwater neutrino telescopes requires the precise knowledge of the water parameters governing light absorption and scattering, as well as a continuous monitoring of these parameters. For this purpose, a stationary underwater device, ASP-15, has been developed by the Baikal collaboration. We describe the basic assumptions and formulae behind ASP-15, the methods how absorption length, scattering length and phase functions are determined, the design of the device, and give some results obtained over many years of operation in conjuction with the Baikal telescope NT200. [Copyright &y& Elsevier]

Abstract: ANTARES is currently the largest operating neutrino telescope located in the Northern Hemisphere. The main goal of ANTARES is to detect high energy neutrinos that are expected from cosmic ray acceleration sites. The construction of ANTARES was completed in 2008. It consists of 12 lines deployed at 2475m depth offshore from Toulon. Data are continuously taken by 885 photo-multipliers that detect the Cherenkov light induced by relativistic charge particles reaching the detector. The status of the experiment will be discussed, together with the latest results including searches for a diffuse high-energy cosmic neutrino flux and for neutrinos from point-like sources. [Copyright &y& Elsevier]

Abstract: The KM3NeT consortium is studying the main technological options for the construction of a research infrastructure in the Mediterranean Sea, hosting a neutrino telescope with an instrumented volume of several km3 and an integrated platform for earth and deep sea sciences. The telescope location will allow the survey of a large part of the Galactic plane, including the Galactic Centre, thus complementing the sky coverage of the IceCube telescope located at the South Pole. A telescope deployed in deep sea water is expected to have a very good angular resolution (of the order of 0.1° for neutrinos with 100TeV energy), providing high sensitivity to point-like sources. The realization of this project will provide the scientific community with a powerful instrument to study and constrain the acceleration mechanisms of some astrophysical objects, including supernova remnants, active galactic nuclei, gamma-ray bursters. Neutrino telescopes can also investigate some of the most fundamental questions on HE physics beyond the standard model, including: the nature of dark matter through the indirect search for WIMPs, the study of subdominant effects on neutrino oscillations, including those possibly induced by the violation of the Lorentz invariance; the study of relic particles (magnetic monopoles, nuclearites) in cosmic radiation, the coincident neutrino emission with gravitational waves. This challenging project will require the installation of thousands of photon detectors with their related electronics and calibration systems several kilometers below sea level. This contribution presents an outline of the technological aspects of the project and a discussion of its main physics goals and expected performances, with a proposed preliminary timeline towards the completion of this instrument. [Copyright &y& Elsevier]

Abstract: The ANTARES Neutrino Telescope was completed in May 2008 and is the first operational Neutrino Telescope in the Mediterranean Sea. The main purpose of the detector is to perform neutrino astronomy and the apparatus also offers facilities for marine and Earth sciences. This paper describes the design, the construction and the installation of the telescope in the deep sea, offshore from Toulon in France. An illustration of the detector performance is given. [Copyright &y& Elsevier]

Abstract: KM3NeT will be a deep submarine research infrastructure in the Mediterranean Sea. It will host a multi-cubic-kilometre neutrino telescope and provide continuous connectivity for long-term deep-sea scientific measurements in the geo- and biological sciences. The KM3NeT neutrino telescope will complement the cubic-kilometre IceCube telescope, implanted in the South Polar ice cap, in its field of view and surpass it substantially in sensitivity. This document describes the major technical aspects of the proposed infrastructure and discusses the expected physics sensitivity of the neutrino telescope. Finally the expected time line towards construction is presented. [Copyright &y& Elsevier]

Abstract: With 59 strings deployed since early 2009, IceCube is more than half complete. The detector has been taking data in different configurations since construction began in 2006. Here we present a summary of recent results from several physical topics addressed by IceCube, like searches for high energy neutrinos from resolved and unresolved sources, searches for WIMP dark matter and searches for exotic physics. Plans for the low-energy extension of IceCube, DeepCore, are also mentioned. [Copyright &y& Elsevier]

Abstract: The Neutrino Telescope NT200 is operated since 1998 and was upgraded to the 10 Mton detector NT200+ in 2005. The preparation towards a km3-scale (Gigaton Volume) detector in Lake Baikal is currently a central activity. As an important milestone, a km3-prototype string, based on completely new technology, has been installed and was operating together with NT200+ since April 2008. Also selected astroparticle physics results from the long-term operation of NT200 are presented. [Copyright &y& Elsevier]

Abstract: The aim of the KM3NeT Project is to build a very large volume (more than 1km3) neutrino telescope in the Mediterranean Sea. The up to date status of the project is presented, and the main physics goals are reviewed. The possibility to search for super-massive exotic particles (magnetic monopoles, nuclearites, Q-balls) is addressed in the final part of the paper. [Copyright &y& Elsevier]

Abstract: Ground based observatories in high energy astro-particle physics are used to explore the non-thermal high energy Universe. These detectors provide data to advance our understanding of cosmic accelerators of cosmic rays, gamma rays and neutrinos up to energies of 1E15eV. The detection principle is in most cases based on shower detection, mostly using photodetectors. This report gives an overview of new techniques in ground based gamma astronomy, cosmic ray air shower arrays and large under water/ice neutrino observatories. [ABSTRACT FROM AUTHOR]

Abstract: In this article we describe the properties of a new 10-in. hemispherical photomultiplier manufactured by Hamamatsu. The prototype has a segmented photocathode and four independent amplification stages. The photomultiplier is one of the main components of a newly designed direction-sensitive optical module to be employed in large-scale underwater neutrino telescopes. The R&D activity has been co-funded by the INFN and the KM3NeT Consortium. The prototype performance fully meets with the design specifications. [Copyright &y& Elsevier]

Abstract: 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 is reviewed. Some physics studies indicating the sensitivity of the KM3NeT neutrino telescope are highlighted and selected major technical design options to be further pursued are described. Finally, the remaining steps towards construction of KM3NeT will be discussed. This document reflects the status of the KM3NeT Conceptual Design Report (CDR), which has been presented to the public for the first time at the VLVnT08 Workshop. [Copyright &y& Elsevier]

Abstract: The NESTOR collaboration is continuing its efforts towards deploying an underwater neutrino telescope. Further site studies (e.g. water light transmission measurements, sedimentation rates, etc.) are being carried out within the context of characterizing a site that may host the proposed KM3NeT infrastructure. In addition, following the successful deployment of a single floor of a NESTOR tower in 2003, five floors are now in the final stages of preparation. The use of these five floors in a form of a truncated tower together with four autonomous strings to be located some 300m away from the tower is being contemplated. This arrangement, named NuBE (for Neutrino Burst Experiment), that may allow the detection neutrinos in coincidence with Gamma Ray Bursts, will be described. [Copyright &y& Elsevier]

Abstract: We review the status of the Lake Baikal Neutrino Experiment. The Neutrino Telescope NT200 has been operating since 1998 and has been upgraded to the 10Mton detector in 2005. We present selected astroparticle physics results from long-term operation of NT200. Also discussed are activities towards acoustic detection of UHE-energy neutrinos, and results of associated science activities. Preparation towards a km3-scale (Gigaton volume) detector in Lake Baikal is currently a central activity. As an important milestone, a km3-prototype string, based on completely new technology, has been installed and is operating together with since April, 2008. [Copyright &y& Elsevier]

Abstract: We review the status of the Baikal Neutrino Experiment. The Neutrino Telescope NT200 is operating in Lake Baikal since 1998 and has been upgraded to the 10Mton detector in 2005. We present selected results concerning astroparticle physics as well as results of environmental studies. We describe the strategy of creating a Gigaton (km3) scale neutrino detector at Lake Baikal. First steps of activities towards a km3 Baikal neutrino telescope, including the development of acoustic high-energy neutrino detection methods are discussed. [Copyright &y& Elsevier]

Abstract: A Vertical Cavity Surface Emitting Laser (VCSEL)-based optical link has been developed for the transmission of nanosecond rise time signals. Uniquely the optical transmitter compensates for variations in the transmitted pulse area due to changes in the temperature of the VCSEL by automatically adjusting the bias current supplied to it. Our new design incorporates a higher performance VCSEL than was previously available, the ZL60052. The optical link exhibits good linearity (to within 12%) over a large dynamic range of 61dB with an acceptable amount of pulse-shape and harmonic distortion across the entire bandwidth of , which is itself limited by the response of the receiver. The transmitter alone exhibits a significantly larger bandwidth of . Future work is required to increase the bandwidth and dynamic range for use with the next generation of photo detectors and digitisation electronics. [Copyright &y& Elsevier]

Abstract: High energy neutrino astronomy is emerging as one of the most exciting options for studying astrophysical processes. To establish neutrino detectability from specific sources, neutrino telescopes of scale are needed. In order to complement the IceCube detector currently under construction in the South Pole, a corresponding Northern Hemisphere detector is needed. The three neutrino telescope projects in the Mediterranean, ANTARES, NEMO and NESTOR have joined forces in order to develop, prepare, construct and operate such a research facility, KM3NeT. To this end, the EU is funding a 3-year design study. In the present paper, the status of the design study is presented and options for the various technical problems are discussed. [Copyright &y& Elsevier]

Abstract: The Roma International Conference on Astroparticle Physics covered gamma-ray astronomy, air-shower experiments and neutrino astronomy on three successive days. I organize my brief summary comments into four topics that cut across these three techniques. They are detector calibration, galactic sources, extra-galactic sources and cosmology. [Copyright &y& Elsevier]

Abstract: We review the status of the Baikal neutrino telescope, which is operating in Lake Baikal since 1998 and has been upgraded to the 10Mton detector in 2005. We present selected physics results on searches for upward going neutrinos, relativistic magnetic monopoles and for very high-energy neutrinos. We describe the strategy of creating a detector on the Gigaton scale at Lake Baikal. First steps of activities towards a Baikal neutrino telescope are discussed. [Copyright &y& Elsevier]

Abstract: This article shows some of the first data from the ANTARES Neutrino Telescope. At the present time (summer 2007) five detector lines are in operation making ANTARES the largest Neutrino Telescope in the northern hemisphere. This report describes the ANTARES project, gives the present status as well as some of the early results obtained. [Copyright &y& Elsevier]

Abstract: The 10Mton scale Neutrino telescope is operating in Lake Baikal since April, 2005. It''s main physics goal is the detection of high energy neutrino cascades in the – energy range. The sensitivity to astrophysical diffuse neutrinos is four times that of it''s predecessor NT200 the telescope that has been operating since 1998, yielding a variety of physics results. A km-scale (Gigaton Volume) Neutrino telescope in Lake Baikal is planned, the R&D phase has started in 2006. We give the basic layout of this Baikal km3-detector, which will be made of building blocks similar to . [Copyright &y& Elsevier]

Abstract: The observation of high-energy extraterrestrial neutrinos is one of the most promising future options to increase our knowledge on non-thermal processes in the universe. Neutrinos are e.g. unavoidably produced in environments where high-energy hadrons collide; in particular, this almost certainly must be true in the astrophysical accelerators of cosmic rays, which thus could be identified unambiguously by sky observations in “neutrino light”. To establish neutrino astronomy beyond the detection of single events, neutrino telescopes of km3 scale are needed. In order to obtain full sky coverage, a corresponding detector in the Mediterranean Sea is required to complement the IceCube experiment currently under construction at the South Pole. The groups pursuing the current neutrino telescope projects in the Mediterranean Sea, ANTARES, NEMO and NESTOR, have joined to prepare this future installation in a 3-year, EU-funded design study named KM3NeT (in the following, this name will also denote the future detector). This report will highlight some of the physics issues to be addressed with KM3NeT and will outline the path towards its realisation, with a focus on the upcoming design study. [Copyright &y& Elsevier]

Abstract: The activities towards the realization of a km3 Cherenkov neutrino detector carried out by the NEMO Collaboration are described. Long-term exploration of a 3500m deep-sea site close to the Sicilian coast has shown that it is optimal for the installation of the detector. The realization of a Phase-1 project, which is under way, will validate the proposed technologies for the realization of the km3 detector on a Test Site at 2000m depth. The realization of a new infrastructure on the candidate site (Phase-2 project) will provide the possibility to test detector components at 3500m depth. [Copyright &y& Elsevier]

Abstract: The Baikal Neutrino Telescope has been operating in its NT200 configuration since April, 1998. The telescope has been upgraded in April, 2005 to the 10Mton scale detector NT200+. It''s main physics goal is the detection of signals from high energy neutrino cascades. NT200+ reaches a 3-year sensitivity of for an all-flavor diffuse cosmic neutrino flux for energies –. Design and sensitivity of NT200+ are described. NT200+ is forming the basic building block of a future km3-scale (gigaton-volume) Baikal Telescope. Research and development work on that next stage detector has started. [Copyright &y& Elsevier]

Abstract: The Baikal neutrino telescope NT200 takes data since April 1998. On April 9th, 2005, the 10-Mton scale detector NT200 was put into operation in Lake Baikal. Selected results obtained during 1998–2002 with the neutrino telescope NT200 are presented. [Copyright &y& Elsevier]

Abstract: This article reports on the status of the ANTARES Neutrino Telescope project as of November 2005. The highlights of the activities during 2005 are the deployment and operation of an instrumentation line which has been taking data since April 2005 and the deployment of a complete mechanical test line in the spring of 2005. The first data from the operation of the instrumentation line is presented. The status report gives the plans for the construction of the full ANTARES detector which is planned for completion in 2007. [Copyright &y& Elsevier]

The current status of neutrino physics is reviewed. With the recent establishment of non-zero neutrino masses and lepton flavour mixing a long-standing open issue has been resolved. However, fundamental questions still remain unanswered, among them the absolute neutrino mass scale, precise values for the mixing angles and CP-phase, and the questions whether the neutrino is its own antiparticle and whether sterile neutrinos do exist in nature. The article describes ideas and plans to tackle these issues in future experiments, and comments on the increasingly important role of neutrinos as messengers for the investigation of astrophysical processes. [Copyright &y& Elsevier]

The ANTARES collaboration is building a deep sea neutrino telescope in the Mediterranean Sea. This detector will cover a sensitive area of typically 0.1 km2 and will be equipped with about 1000 optical modules. Each of these optical modules consists of a large area photomultiplier and its associated electronics housed in a pressure resistant glass sphere. The design of the ANTARES optical module, which is a key element of the detector, has been finalized following extensive R&D studies and is reviewed here in detail. [Copyright &y& Elsevier]

Abstract: The NEMO collaboration team has undertaken a Phase-2 project, which aims at the realization and installation of a new infrastructure at the Capo Passero (Italy) deep-sea site at a depth of 3500m. With this objective in mind, a fully equipped tower with 8-storey hosting two optical modules at each end is under construction. Following a well established procedure, 32 optical modules have been assembled. The optical module consists of a large area photomultiplier tube enclosed in a pressure resistant glass sphere with a diameter of 13in. The photomultiplier is a R7081 type, produced by Hamamatsu, with a photocathode area with a diameter of 10in. and 10 dynodes. Mechanical and optical contacts between the front of the photomultiplier tube and the glass surface are ensured by an optical bi-component silicone gel. A mu-metal cage is used to shield the photomultiplier against the influence of the Earth's magnetic field. [Copyright &y& Elsevier]

Abstract: Deep-sea neutrino telescopes consist of an array of photomultipliers to detect Cherenkov light emitted by neutrino-induced muons and particle showers in the surrounding sea water, allowing for reconstruction of the neutrino direction from position and timing of the Cherenkov photons. Since the photomultipliers are in most cases mounted on flexible structures, e.g. lines, and move with the sea current, a positioning system is required to determine the precise location of each sensor. The positioning system of the ANTARES neutrino telescope is based on acoustic triangulation using hydrophones mounted along the lines in combination with tiltmeters and compasses and provides centimetre precision alignment. For the future KM3NeT detector an Optical Module with integrated Piezo sensors for position calibration is proposed as a cost-effective solution. The performance of this system is tested with several sensors of the AMADEUS project, which is integrated in ANTARES to study the background for acoustic detection of highest energy neutrinos. [ABSTRACT FROM AUTHOR]

Abstract: The construction of a scale underwater telescope for high energy neutrinos is a fundamental task for the development of the 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 high energy neutrino component of cosmic rays. In this framework the front-end and readout electronics is one 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. [Copyright &y& Elsevier]

The IceCube Neutrino Observatory is located at the geographic South Pole and consists of over 5000 optical sensors embedded in the Antarctic ice along with 81 cosmic ray detector stations on the surface. IceCube was designed to detect high energy neutrinos from extreme astrophysical environments which are potential cosmic ray acceleration sites, such as active galactic nuclei, gamma ray bursts and supernova remnants. The discovery of astrophysical neutrinos by IceCube in 2013 heralded the beginning of neutrino astronomy, and we continue to collect data and explore the properties and potential sources of these neutrinos. An expanded successor called IceCube-Gen2 is in development, with updated optical sensors and calibration devices, and an expanded surface veto. The IceCube-Gen2 detector will search for the sources of cosmic neutrinos and will also include an infill component which will investigate fundamental neutrino physics using atmospheric neutrinos. I will discuss the latest results from IceCube, and the status of IceCube-Gen2. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes the timing calibration system for the NEutrino Mediterranean Observatory (NEMO) underwater neutrino telescope. The NEMO Project aims at the construction of a km3 detector, equipped with a large number of photomultipliers, in the Mediterranean Sea. We foresee a redundant system to perform the time calibration of our apparatus: (1) A two-step procedure for measuring the offsets in the time measurements of the NEMO optical sensors, so as to measure separately the time delay for the synchronization signals to reach the offshore electronics and the response time of the photomultipliers to calibration signals delivered from a pulser through an optical fibre distribution system; (2) An all-optical procedure for measuring the differences in the time offsets of the different optical modules by means of common light sources. Such a system can be extended to work for a very large apparatus, even for complex arrangements of widely spaced sensors. The NEMO prototyping activities ongoing at a test site off the coast of Sicily will allow the system described in this work to be operated and tested in situ this year. [Copyright &y& Elsevier]

Abstract: In 2006–2010, several radio frequency (RF) detectors and calibration equipment were deployed as part of the IceCube array at depths between 5 and 1400m in preparation for a future large scale GZK neutrino detector. IceCube''s deep holes and well-established data handling system provide a unique opportunity for deep-ice RF detection studies at the South Pole. We will present verification and calibration results as well as a status-review of ongoing analyses such as ice-properties, RF noise and reconstruction algorithms. [Copyright &y& Elsevier]

Abstract: With completion expected in 2011, the IceCube Neutrino Observatory is approaching the scale required for high energy neutrino astronomy. Before completion, the data taken with the deployed strings of the IceCube detector allows the testing of different procedures of searching for high energy neutrinos of extraterrestrial origin. This work describes some of the approaches used by the IceCube collaboration to search for point-like and extended sources. Emphasis will be placed on the results obtained from the analysis of the Cygnus region using data from the combined detector configuration IceCube-22-strings and AMANDA. The method presented here uses a two-point analysis to detect, within an extended region, event patterns which might go undetected in conventional point-source analysis. [ABSTRACT FROM AUTHOR]

Abstract: KM3NeT is a future European research infrastructure, which will host a neutrino telescope with a volume of at least 1Km3 in the deep Mediterranean Sea. This challenging project will require the installation of thousands of photon detectors with their related electronics and calibration systems several kilometres below the sea level. The design builds on the extensive experience gained in the pioneering ANTARES, NEMO and NESTOR underwater neutrino telescope projects. However, independent of the technical and scientific challenges inherent to such a project, new solutions must be pursued in order to significantly increase the cost effectiveness. This contribution presents the first results of a finite element analysis (FEA) performed at CPPM, in association with the Schott glass R&D department, for an alternative low cost glass pressure housing for optical modules in the KM3NeT neutrino telescope. [ABSTRACT FROM AUTHOR]

Abstract: KM3NeT is a future research facility in the Mediterranean Sea which will include a cubic-kilometre-scale high-energy neutrino telescope. During the Design Study, detector optimisation studies have been pursued in conjunction with technical developments. The KM3NeT consortium is now in the phase of completing a Technical Design Report. We will review recent results obtained in optimising the geometrical layout of the detector, and describe the physics simulations performed as well as the methods employed for these optimisations. [ABSTRACT FROM AUTHOR]

Abstract: The KM3NeT research infrastructure in the deep Mediterranean Sea will host a multi-cubic-kilometre neutrino telescope and provide connectivity for continuous, long-term measurements of earth and sea sciences, such as geology, marine biology and oceanography. The KM3NeT neutrino telescope will complement the IceCube telescope currently being installed at the South Pole in its field of view and surpass its sensitivity by a substantial factor. In this document the major aspects of the KM3NeT technical design are described and the expected physics sensitivity is discussed. Finally, the expected time line towards construction is presented. [ABSTRACT FROM AUTHOR]

Abstract: The latest results and the activities towards the construction of a km3 Cherenkov neutrino detector carried out by the NEMO Collaboration are described. Long-term exploration of a 3500m deep-sea site close to the Sicilian coast has shown that it is optimal for the installation of the detector. The NEMO Phase-1 project has validated several technologies proposed for the construction of the km3 detector on a test site at 2000m depth. The new infrastructure on the candidate Capo Passero site set up as part of the Phase-2 project will provide the possibility to test detector components at 3500m depth. [ABSTRACT FROM AUTHOR]

Abstract: The IceCube observatory is the first cubic kilometre scale instrument in the field of high-energy neutrino astronomy and cosmic rays. In 2009, following five successful deployment seasons, IceCube consisted of 59 strings of optical modules in the South Pole ice, together with 118 air shower detectors in the IceTop surface array. The range of physics topics includes neutrino signals from astrophysical sources, dark matter, exotic particle physics, cosmic rays, and atmospheric neutrinos. The current IceCube status and selected results are described. Anticipated future developments are also discussed, in particular the Deep Core low energy subarray which was recently deployed. [ABSTRACT FROM AUTHOR]

Abstract: The evidence of the existing of UHE cosmic rays and its possible connection to UHE neutrino suggests the building of an acoustic telescope for neutrino, exploiting thermo-acoustic effect. We present software for neutrino acoustic signal detection and localization. The main points discussed here are the sea noise model, the determination of time differences of arrival (TDOA) between hydrophones signals, the source localization algorithm, and the telescope geometry effect. The effect of TDOAs errors and telescope geometry on the localization accuracy is also discussed. [Copyright &y& Elsevier]

Abstract: UHE neutrinos with are produced by ultra-high energy cosmic rays (UHECR) interacting with CMB photons (cosmogenic neutrinos) and by top-down sources, such as topological defects (TDs) and superheavy dark matter (SHDM). Cosmogenic neutrinos are reliably predicted and their fluxes can be numerically evaluated using the observed flux of UHECR. The lower limit for the flux is obtained for the case of pure proton composition of the observed UHECR. The rigorous upper limit for cosmogenic neutrino flux also exists. The maximum neutrino energy is determined by maximum energy of acceleration, which at least for the shock acceleration is expected not to exceed –. The top-down sources provide neutrino energies a few orders of magnitude higher, and this can be considered as a signature of these models. UHE neutrino fluxes are discussed for production by SHDM and TDs. [Copyright &y& Elsevier]

Abstract: We show that charm production gives significant enhancement to a flux of very high energy neutrinos from astrophysical sources with jets driven by central engines, such as gamma ray bursts or supernovae with jets. We demonstrate that neutrino flux from semi-leptonic decays of charmed mesons is subject to much less hadronic and radiative cooling than the conventional flux from pion and kaon decays. We discuss implications of our results for future ultrahigh energy neutrino experiments. [Copyright &y& Elsevier]

Abstract: South Pole ice is predicted to be the best medium for acoustic neutrino detection. Moreover, ice is the only medium in which all three dense-medium detection methods (optical, radio, and acoustic) can be used to monitor the same interaction volume. Events detected in coincidence between two methods allow significant background rejection confidence, which is necessary to study rare GZK neutrinos. In 2007 and 2008 the South Pole Acoustic Test Setup (SPATS) was installed as a research and development project associated with the IceCube experiment. The purpose of SPATS is to measure the acoustic ice properties at the South Pole in order to determine the feasibility of a future large hybrid array. The deployment and performance of SPATS are described, as are first results and work in progress on the sound speed, background noise, and attenuation. [Copyright &y& Elsevier]