48 research outputs found

    GRID-Launcher v.1.0

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    GRID-launcher-1.0 was built within the VO-Tech framework, as a software interface between the UK-ASTROGRID and a generic GRID infrastructures in order to allow any ASTROGRID user to launch on the GRID computing intensive tasks from the ASTROGRID Workbench or Desktop. Even though of general application, so far the Grid-Launcher has been tested on a few selected softwares (VONeural-MLP, VONeural-SVM, Sextractor and SWARP) and on the SCOPE-GRID

    Demonstration and Comparison of Operation of Photomultiplier Tubes at Liquid Argon Temperature

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    Liquified noble gases are widely used as a target in direct Dark Matter searches. Signals from scintillation in the liquid, following energy deposition from the recoil nuclei scattered by Dark Matter particles (e.g. WIMPs), should be recorded down to very low energies by photosensors suitably designed to operate at cryogenic temperatures. Liquid Argon based detectors for Dark Matter searches currently implement photo multiplier tubes for signal read-out. In the last few years PMTs with photocathodes operating down to liquid Argon temperatures (87 K) have been specially developed with increasing Quantum Efficiency characteristics. The most recent of these, Hamamatsu Photonics Mod. R11065 with peak QE up to about 35%, has been extensively tested within the R&D program of the WArP Collaboration. During these testes the Hamamatsu PMTs showed superb performance and allowed obtaining a light yield around 7 phel/keVee in a Liquid Argon detector with a photocathodic coverage in the 12% range, sufficient for detection of events down to few keVee of energy deposition. This shows that this new type of PMT is suited for experimental applications, in particular for new direct Dark Matter searches with LAr-based experiments

    The DAME/VO-Neural Infrastructure: an Integrated Data Mining System Support for the Science Community

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    Astronomical data are gathered through a very large number of heterogeneous techniques and stored in very diversified and often incompatible data repositories. Moreover in the e-science environment, it is needed to integrate services across distributed, heterogeneous, dynamic "virtual organizations" formed by different resources within a single enterprise and/or external resource sharing and service provider relationships. The DAME/VONeural project, run jointly by the University Federico II, INAF (National Institute of Astrophysics) Astronomical Observatories of Napoli and the California Institute of Technology, aims at creating a single, sustainable, distributed e-infrastructure for data mining and exploration in massive data sets, to be offered to the astronomical (but not only) community as a web application. The framework makes use of distributed computing environments (e.g. S.Co.P.E.) and matches the international IVOA standards and requirements. The integration process is technically challenging due to the need of achieving a specific quality of service when running on top of different native platforms. In these terms, the result of the DAME/VO-Neural project effort will be a service-oriented architecture, obtained by using appropriate standards and incorporating Grid paradigms and restful Web services frameworks where needed, that will have as main target the integration of interdisciplinary distributed systems within and across organizational domains.Comment: 10 pages, Proceedings of the Final Workshop of the Grid Projects of the Italian National Operational Programme 2000-2006 Call 1575; Edited by Cometa Consortium, 2009, ISBN: 978-88-95892-02-

    A web application for photometric redshift estimation

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    In the era of massive astronomical datasets, efficient identification of candidate quasars and the reconstruction of their three dimensional distribution in the Universe is a key requirement for constraining some of the main issues regarding the formation and evolution of QSOs. A method for the determination of photometric redshifts of QSOs based on multiwavelength photometry and on a combination of data mining techniques will be discussed. This procedure, specifically suited for accompanying the candidate selection method discussed in (D’Abrusco et al. 2008), makes use of specific tools developed under the EuroVO and NVO frameworks for data gathering, pre-processing and mining, while relying on the scaling capabilities of the computing grid. This method allowed us to obtain photometric redshifts with an increased accuracy (up to 30%) with respect to the literature

    Measurement of the atmospheric muon depth intensity relation with the NEMO Phase-2 tower

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    The results of the analysis of the data collected with the NEMO Phase-2 tower, deployed at 3500 m depth about 80 km off-shore Capo Passero (Italy), are presented. Cherenkov photons detected with the photomultipliers tubes were used to reconstruct the tracks of atmospheric muons. Their zenith-angle distribution was measured and the results compared with Monte Carlo simulations. An evaluation of the systematic effects due to uncertainties on environmental and detector parameters is also included. The associated depth intensity relation was evaluated and compared with previous measurements and theoretical predictions. With the present analysis, the muon depth intensity relation has been measured up to 13 km of water equivalent.Comment: submitted to Astroparticle Physic

    Deep sea tests of a prototype of the KM3NeT digital optical module

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    The first prototype of a photo-detection unit of the future KM3NeT neutrino telescope has been deployed in the deepwaters of the Mediterranean Sea. This digital optical module has a novel design with a very large photocathode area segmented by the use of 31 three inch photomultiplier tubes. It has been integrated in the ANTARES detector for in-situ testing and validation. This paper reports on the first months of data taking and rate measurements. The analysis results highlight the capabilities of the new module design in terms of background suppression and signal recognition. The directionality of the optical module enables the recognition of multiple Cherenkov photons from the same (40)Kdecay and the localisation of bioluminescent activity in the neighbourhood. The single unit can cleanly identify atmospheric muons and provide sensitivity to the muon arrival directions

    Long term monitoring of the optical background in the Capo Passero deep-sea site with the NEMO tower prototype

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    The NEMO Phase-2 tower is the first detector which was operated underwater for more than 1 year at the "record" depth of 3500 m. It was designed and built within the framework of the NEMO (NEutrino Mediterranean Observatory) project. The 380 m high tower was successfully installed in March 2013 80 km offshore Capo Passero (Italy). This is the first prototype operated on the site where the Italian node of the KM3NeT neutrino telescope will be built. The installation and operation of the NEMO Phase-2 tower has proven the functionality of the infrastructure and the operability at 3500 m depth. A more than 1 year long monitoring of the deep water characteristics of the site has been also provided. In this paper the infrastructure and the tower structure and instrumentation are described. The results of long term optical background measurements are presented. The rates show stable and low baseline values, compatible with the contribution of K-40 light emission, with a small percentage of light bursts due to bioluminescence. All these features confirm the stability and good optical properties of the site.Funded by SCOAP3Adrián Martínez, S.; Aiello, S.; Ameli, F.; Anghinolfi, M.; Ardid Ramírez, M.; Barbarino, G.; Barbarito, E.... (2016). Long term monitoring of the optical background in the Capo Passero deep-sea site with the NEMO tower prototype. European Physical Journal C: Particles and Fields. 76(68):1-11. https://doi.org/10.1140/epjc/s10052-016-3908-0S1117668M. Ageron et al., ANTARES: the first undersea neutrino telescope. Nucl. Instr. Methods A 656, 11 (2011)V. Aynutdnov for the Baikal Coll., The BAIKAL neutrino project: results and perspective. Nucl. Instr. Methods. A 628, 115 (2011)A. Achterberg et al., First year performance of the IceCube neutrino telescope. Astropart. Phys. 26, 155 (2006)M.G. Aartsen et al., Evidence for high-energy extraterrestrial neutrinos at the IceCube detector. Science 342, 1242856 (2013)M.G. Aartsen et al., Observation of high-energy astrophysical neutrinos in three years of IceCube data. Phys. Rev. Lett. 113, 101101 (2014)M.G. Aartsen et al., Evidence for astrophysical muon neutrinos from the northern sky with IceCube. Phys. Rev. Lett. 115, 081102 (2015)E. Migneco et al., Status of NEMO. Nucl. Instr. Methods A 567, 444 (2006)E. Migneco et al., Recent achievements of the NEMO project. Nucl. Instr. Methods A 588, 111 (2008)A. Capone et al., Recent results and perspectives od the NEMO project. Nucl. Instr. Methods A 602, 47 (2009)M. Taiuti et al., The NEMO project: a status report. Nucl. Instr. Methods A 626, S25 (2011)S. Aiello et al., Measurement of the atmospheric muon flux of the NEMO Phase-1 detector. Astropart. Phys. 33, 263 (2010)A. Capone et al., Measurements of light transmission in deep sea with the AC9 transmissometer. Nucl. Instr. Methods A 487, 423 (2002)G. Riccobene et al., Deep seawater inherent optical properties in the Southern Ionian Sea. Astropart. Phys. 27, 1 (2007)A. Rubino et al., Abyssal undular vortices in the Eastern Mediterranean basin. Nat. Commun. 3, 834 (2012)KM3NeT web site. www.km3net.orgM. Sedita for the NEMO collaboration, Electro-optical cable and power feeding system for the NEMO Phase-2 project. Nucl. Instr. Methods A 567, 531 (2006)R. Cocimano for the NEMO collaboration, A comparison of AC and DC power feeding systems based on the NEMO experiences. Nucl. Instr. Methods A 602, 171 (2009)A. Orlando for the NEMO collaboration, On line monitoring of the power control and engineering parameters systems of the NEMO Phase-2 tower. Nucl. Instr. Methods. A 602, 180 (2009)M. Musumeci for the NEMO collaboration, Construction and deployment issues for a km {3} 3 underwater detector. Nucl. Instr. Methods. A 567, 545 (2006)S. Aiello et al., The optical modules of the phase-2 of the NEMO project. JINST 8, P07001 (2013)E. Leonora, S. Aiello, Design and assembly of the optical modules for phase-2 of the NEMO project. Nucl. Instr. Methods A 725, 234 (2013)S. Aiello et al., Procedures and results of the measurements on large area photomultipliers for the NEMO project. Nucl. Instr. Methods A 614, 206 (2010)C.A. Nicolau for the NEMO collaboration, An FPGA-based readout electronics for neutrino telescopes. Nucl. Instr. Methods A 567, 552 (2006)M. Cordelli et al., PORFIDO: oceanographic data for neutrino telescopes. Nucl. Instr. Methods A 626–627, S109 (2011)F. Ameli, The data acquisition and transport design for NEMO Phase-1. IEEE Trans. Nucl. Sci. 55(1), 233 (2008)A. D’Amico for the NEMO collaboration, Design of the optical Raman amplifier for the shore station of NEMO Phase-2. Nucl. Instr. Methods A 626–627, S173 (2011)T. Chiarusi for the NEMO collaboration, Scalable TriDAS for the NEMO project. Nucl. Instr. Methods A 630, 107 (2011)S. Viola et al., NEMO-SMO acoustic array: a deep-sea test of a novel acoustic positioning system for a km 3^3 3 -scale underwater neutrino telescope. Nucl. Instr. Methods A 725, 207 (2013)S. Viola et al., in Underwater acoustic positioning system for the SMO and KM3NeT-Italia projects. AIP Conference Proceedings 1630, 134 (2014)M. Circella for the NEMO collaboration, Time calibration of the NEutrino Mediterranean Observatory (NEMO). Nucl. Instr. Methods A 602, 187 (2009)S. Aiello et al., Measurement of the atmospheric muon depth intensity relation with the NEMO phase-2 tower. Astropart. Phys. 66, 1 (2015)C. Hugon for the ANTARES and KM3NeT collaborations, Step by step simulation of phototubes for the KM3NeT and ANTARES optical modules. Nucl. Instr. Methods A 787, 189 (2015)Ch. Tamburini et al., Deep-sea bioluminescence blooms after dense water formation at the ocean surface. PLOS One 8, e67523 (2013
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