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.

P. Amaudruz 13a M. Arneodo 14 A. Arvidson 15 B. Badelek I7~++ G. Baum ~ J. Beaufays 9b,** I.G. Bird 4c,* M. Botje 13 C. Broggini 8d w. Bruckner 4* A. Brüll 3*, W.J. Burger 13e J~Ciborowski 9~**, R. van Dantzig 9,**, H. Döbbeling 4g,*, J. Domingo 13h J~Drinkard 12 H. Engelien 3,*, M.I. Ferrero 14 L. Fluri 8 P. Grafstrom 15i D. von Harrach ~ M. van der Heijden 9,**, C. Heusch 12 Q~Ingram 13 K. Janson 15 M. de Jong 9,** E.M. Kabuss 41.*, R. Kaiser 3*, T.J. Ketel 9,**, F. Klein 6,* B. Korzen ‘~“~‘, U. Krüner 18,* S. Kullander ~ U. Landgraf 3*, F. Lettenström 12 T. Lindqvist ‘~ G.K. Mallot 6,* C. Mariotti 14 G. van Middelkoop 2,9,** A. Milsztajn ~, Y. Mizuno 4k,* J~Nassalski 16,9,-4-,** D. Nowotny 4.*, N. Pavel 18(,~ c~Peroni 14 H. Peschel 18m,* B. Povh ~,5,* R. Rieger 6,* K. Rith 4,*, K. Röhrich bn,* E. Rondio 17,++ L. Ropelewski 17.±+ A. Sandacz ~ C. Scholz ~,*, R. Schumacher 13o U. Sennhauser ~ F. Sever 1q,~ T.-A. Shibata 5,*, M. Siebler “i’, A. Simon 4,*, A. Staiano 14 G. Taylor br M. Treichel 4s,*, M. Virchaux ~ J.L. Vuilleumier 8 T. Walcher ~ R. Windmolders ~ and F. Zetsche ~,*

The final oscillation analysis of the complete set of data collected by CHORUS in the years 1994-1997 is presented. Reconstruction algorithms of data extracted by electronic detectors were improved and the data recorded in the emulsion target were analysed by new automated scanning systems, allowing the use of a new method for event reconstruction in emulsion. CHORUS has applied these new techniques to the sample of 1996-1997 events for which no muons were observed in the electronic detectors. Combining the new sample with the data analysed in previous papers, the overall sensitivity of the experiment to the nu(tau) appearance is thus improved. In a two-neutrino mixing scheme, a 90% C.L. upper limit of sin(2)2 theta(mu tau) < 4.4 x 10(-4) is set for large Delta m(2), improving by a factor 1.5 the previously published CHORUS result. (C) 2007 Elsevier B.V. All rights reserved.

The proton and deuteron structure functions F p 2 and F d 2 were measured in the kinematic range 0.006 < x < 0.6 and 0.5 < Q < 75 GeV, by inclusive deep inelastic muon scattering at 90, 120, 200 and 280 GeV. The measurements are in good agreement with earlier high precision results. The present and earlier results together have been parametrised to give descriptions of the proton and deuteron structure functions F2 and their uncertainties over the range 0.006 < x < 0.9.

We present a leading order QCD analysis of a sample of neutrino induced charged-current events with two muons in the final state originating in the lead-scintillating fibre calorimeter of the CHORUS detector. The results are based on a sample of 8910 neutrino and 430 antineutrino induced opposite-sign dimuon events collected during the exposure of the detector to the CERN Wide Band Neutrino Beam between 1995 and 1998. The analysis yields a value of the charm quark mass of m(c) = (1.26 +/- 0.16 +/- 0.09) GeV/c(2) and a value of the ratio of the strange to non-strange sea in the nucleon Of K = 0.33 +/- 0.05 +/- 0.05, improving the results obtained in similar analyses by previous experiments. (c) 2008 Elsevier B.V. All rights reserved.

In this paper a search for associated charm production both in neutral and charged current $\nu$-nucleus interactions is presented. The improvement of automatic scanning systems in the {CHORUS} experiment allows an efficient search to be performed in emulsion for short-lived particles. Hence a search for rare processes, like the associated charm production, becomes possible through the observation of the double charm-decay topology with a very low background. About 130,000 $\nu$ interactions located in the emulsion target have been analysed. Three events with two charm decays have been observed in the neutral-current sample with an estimated background of 0.18$\pm$0.05. The relative rate of the associated charm cross-section in deep inelastic $\nu$ interactions, $\sigma(c\bar{c}\nu)/\sigma_\mathrm{NC}^\mathrm{DIS}= (3.62^{+2.95}_{-2.42}({stat})\pm 0.54({syst}))\times 10^{-3}$ has been measured. One event with two charm decays has been observed in charged-current $\nu_\mu$ interactions with an estimated background of 0.18$\pm$0.06 and the upper limit on associated charm production in charged-current interactions at 90% C.L. has been found to be $\sigma (c\bar{c} \mu^-)/\sigma_\mathrm{CC} < 9.69 \times 10^{-4}$.

ANTARES is a neutrino telescope being deployed in the Mediterranean Sea. It consists of a three dimensional array of photomultiplier tubes that can detect the Cherenkov light induced by charged particles produced in the interactions of neutrinos with the surrounding medium. High angular resolution can be achieved, in particular when a muon is produced, provided that the Cherenkov photons are detected with sufficient timing precision. Considerations of the intrinsic time uncertainties stemming from the transit time spread in the photomultiplier tubes and the mechanism of transmission of light in sea water lead to the conclusion that a relative time accuracy of the order of 0.5 ns is desirable. Accordingly, different time calibration systems have been developed for the ANTARES telescope. In this article, a system based on Optical Beacons, a set of external and well-controlled pulsed light sources located throughout the detector, is described. This calibration system takes into account the optical properties of sea water, which is used as the detection volume of the ANTARES telescope. The design, tests, construction and first results of the two types of beacons, LED and laser-based, are presented.

A full-scale mechanical prototype line was deployed to a depth of 2500m to test the leak tightness of the electronics containers and the pressure-resistant properties of an electromechanical cable under evaluation for use in the ANTARES deep-sea neutrino telescope. During a month-long immersion study, line parameter data were taken using miniature autonomous data loggers and shore-based optical time domain reflectometry. Details of the mechanical prototype line, the electromechanical cable and data acquisition are presented. Data taken during the immersion study revealed deficiencies in the pressure resistance of the electromechanical cable terminations at the entry points to the electronics containers. The improvements to the termination, which have been integrated into subsequent detection lines, are discussed. The line also allowed deep-sea acoustic measurements with a prototype hydrophone system. The technical setup of this system is described, and the first results of the data analysis are presented.

The CHORUS experiment, designed to search for νμ→ντ oscillations, consists of a nuclear emulsion target and electronic detectors. In this paper, results on the production of charged particles in a small sample of charged-current neutrino– and anti-neutrino–nucleus interactions at high energy are presented. For each event, the emission angle and the ionization features of the charged particles produced in the interaction are recorded, while the standard kinematic variables are reconstructed using the electronic detectors. The average multiplicities for charged tracks, the pseudo-rapidity distributions, the dispersion in the multiplicity of charged particles and the KNO scaling are studied in different kinematical regions. A study of quasi-elastic topologies performed for the first time in nuclear emulsions is also reported. The results are presented in a form suitable for use in the validation of Monte Carlo generators of neutrino–nucleus interactions.

In 2005, the ANTARES Collaboration deployed and operated at a depth of 2500 m a so-called Mini Instrumentation Line equipped with Optical Modules (MILOM) at the ANTARES site. The various data acquired during the continuous operation from April to December 2005 of the MILOM confirm the satisfactory performance of the Optical Modules, their front-end electronics and readout system. as well as the calibration devices of the detector. The in situ measurement of the Optical Module time response yields a resolution better than 0.5 ns. The performance of the acoustic positioning system, which enables the spatial reconstruction of the ANTARES detector with a precision of about 10 cm, is verified. These results demonstrate that with the full ANTARES neutrino telescope the design angular resolution of better than 0.3 degrees can be realistically achieved. Crown Copyright (c) 2006 Published by Elsevier B.V. All rights reserved.

After completion of the data taking for the v(mu) -> v(tau) oscillation search, the CHORUS lead-scintillator calorimeter was used in the 1998 run as an active target. High-statistics samples of charged-current interactions were collected in the CERN SPS west area neutrino beam. This beam contained predominantly muon (anti-)neutrinos from sign-selected pious and kaons. We measure the flux and energy spectrum of the incident neutrinos and compare them with beam simulations. The neutrino-nucleon and anti-neutrino-nucleon differential cross-sections are measured in the range 0.01 < x < 0.7, 0.05 < y < 0.95, 10 < E-v < 200 GeV. We extract the neutrino-nucleon structure functions F-2(x, Q(2)), xF(3) (x, Q(2)), and R(x, Q2) and compare these with results from other experiments. (c) 2005 Elsevier B.V. All rights reserved.

A systematic search for superfragments (charmed nuclei) has been performed in 22 200 neutrinoemulsion interactions obtained with the CHORUS experiment making use of automatic off-line image analysis. The absence of candidates provides an upper limit for the superfragment production rate of 1.9 x 10(-4) (90% C.L.) relative to neutrino charged-current interactions at an average neutrino energy of 27 GeV. In the same analysis 28 hyperfragment decays were found. For the first time, a production rate of hyperfragments in neutrino-emulsion interactions was obtained. The value of the hyperfragment production rate relative to the neutrino charged-current cross-section was found to be (2.0 +/- 0.4(stat) +/- 0.3 (syst)) x 10(-3). (c) 2005 Elsevier B.V. All rights reserved.

During the years 1994-1997, the emulsion target of the CHORUS detector was exposed to the wide-band neutrino beam of the CERN SPS of 27 GeV average neutrino energy. In total about 100 000 charged-current neutrino interactions were located in the nuclear emulsion target and fully reconstructed. From this sample of events which was based on the data acquired by new automatic scanning systems, 1048 charged-current interactions with a Do in the final state were selected by a pattern recognition program and confirmed as neutral-particle decays through visual inspection. The ratio of decay branching fractions of the Do into four charged particles to two charged particles was measured to be B(D-0 -> V4)/B(D-0 -> V2) = 0.207 +/- 0.016 +/- 0.004. The inclusive measurement of the observed production rate of the Do with a decay into four charged prongs in combination with external measurements of this topological branching ratio was used to determine the total Do production rate by neutrinos without additional assumption on the branching fractions. The value of this rate relative to the charged-current cross-section was found to be sigma (D-0) / sigma (CC) = 0.0269 +/- 0.0018 +/- 0.0013. In addition, the same normalization method was used to deduce the inclusive topological decay rate into final states with neutral particles only. A value of 0.218 +/- 0.049 +/- 0.036 was found for this branching fraction. From an observed number of three charged six-prong events the branching ratio into six charged particles was determined to be (1.2(-0.9)(+1.3) +/- 0.2) x 10(-3). A measurement of the energy dependence of the D-0 production by neutrinos relative to the total charged-current cross-section is also reported. This measurement was used to deduce for m(c), the effective charm-quark mass, a value of (1.42 +/- 0.08) GeV/c(2). (c) 2005 Elsevier B.V. All rights reserved.

The ANTARES neutrino telescope is a large photomultiplier array designed to detect neutrino-induced upward-going muons by their Cherenkov radiation. Understanding the absorption and scattering of light in the deep Mediterranean is fundamental to optimising the design and performance of the detector. This paper presents measurements of blue and UV light transmission at the ANTARES site taken between 1997 and 2000. The derived values for the scattering length and the angular distribution of particulate scattering were found to be highly correlated, and results are therefore presented in terms of an absorption length lambda_abs and an effective scattering length lambda_sct^eff. The values for blue (UV) light are found to be lambda_abs ~ 60(26) m, lambda_sct^eff ~ 265(122) m, with significant (15%) time variability. Finally, the results of ANTARES simulations showing the effect of these water properties on the anticipated performance of the detector are presented.

In this paper we discuss the mapping of the physical problem of 2D crystallization with spherical boundary conditions onto a Simulated Annealing model, and the mapping of this model onto a parallel computer. We discuss some aspects of the finetuning of the simulation code and the overall behaviour, stability and scalability, of our parallel implementation.

S. Adrián-Martíneza, I. Al Samaraib, A. Albertc, M. Andréd, M. Anghinolfie, G. Antonf, L. Antonf, S. Anvarg, M. Ardida, T. Astraatmadjah,1, J.-J. Aubertb, B. Bareti, S. Basaj, V. Bertinb, S. Biagik,l, C. Bigongiarim, C. Bogazzih, M. Bou-Caboa, B. Bouhoui, M.C. Bouwhuish, J. Brunnerb, J. Bustob, A. Caponen,o, C. Cârloganup, J. Carrb, S. Cecchinik, Z. Charifb, Ph. Charvisq, T. Chiarusik, M. Circellar, R. Conigliones, L. Coreb, H. Costantinib, P. Coyleb, A. Creusoti, C. Curtilb, G. De Bonisn,o, M.P. Decowskih, I. Dekeysert, A. Deschampsq, C. Distefanos, C. Donzaudi,u, D. Dornicm,b, Q. Dorostiv, D. Drouhinc, T. Eberlf, U. Emanuelem, A. Enzenhöferf, J.-P. Ernenweinb, S. Escoffierb, K. Fehnf, P. Fermanin,o, M. Ferria, S. Ferryw, V. Flaminiox,y, F. Folgerf, U. Fritschf, J.-L. Fudat, S. Galatàb, P. Gayp, K. Geyerf, G. Giacomellik,l, V. Giordanos, J.P. Gómez-Gonzálezm, K. Graff, G. Guillardp, G. Hallewellb, M. Hamalz, H. van Harenaa, A.J. Heijboerh, Y. Helloq, J.J. Hernández-Reym, B. Heroldf, J. Hößlf, C.C. Hsuh, M. de Jongh,1, M. Kadlerab, O. Kalekinf, A. Kappesf,2, U. Katzf, O. Kavatsyukv, P. Kooijmanh,ac,ad, C. Kopperh,f, A. Kouchneri, I. Kreykenbohmab, V. Kulikovskiyae,al, R. Lahmannf, G. Lambardm, G. Larosaa, D. Lattuadas, D. Lefèvret, G. Limh,ad, D. Lo Prestiaf,ag, H. Loehnerv, S. Loucatosw, F. Louisg, S. Manganom, M. Marcelinj, A. Margiottak,l, J.A. Martínez-Moraa, S. Martinit, A. Melif, T. Montarulir,ah, M. Morgantix,3, L. Moscosoi,w,4, H. Motzf, M. Nefff, E. Nezrij, D. Palioselitish, G.E. Păvălaşai, K. Payetw, J. Petrovich, P. Piattellis, V. Popaai, T. Pradieraj, E. Presanih, C. Raccac, C. Reedh, G. Riccobenes, C. Richardtf, R. Richterf, C. Rivièreb, A. Robertt, K. Roenschf, A. Rostovtsevak, J. Ruiz-Rivasm, M. Rujoiuai, G.V. Russoaf,ag, D.F.E. Samtlebenh, P. Sapienzas, J. Schmidf, J. Schnabelf, F. Schöckf, J.-P. Schullerw, F. Schüsslerw, T. Seitzf, R. Shanidzef, F. Simeonen,o, A. Spiesf, M. Spuriok,l, J.J.M. Steijgerh, Th. Stolarczykw, A. Sánchez-Losam, M. Taiutie,al, C. Tamburinit, A. Trovatoaf, B. Vallagew, C. Valléeb, V. Van Elewycki, M. Vecchib, P. Verninw, E. Visserh, S. Wagnerf, G. Wijnkerh, J. Wilmsab, E. de Wolfh,ad, H. Yepesm, D. Zaborovak, J.D. Zornozam and J. Zúñigam

From 1994 to 1997, the emulsion target of the CHORUS detector was exposed to the wideband neutrino beam of the CERN SPS. In total about 100 000 charged-current neutrino interactions were located in the nuclear emulsion target and fully reconstructed. From this sample of events based on the data acquired by new automatic scanning systems; 2013 charm-decay events were selected by a pattern recognition program. They were confirmed as decays through visual inspection. Based on these events, the effective branching ratio of charmed particles into muons was determined to be (B) over bar (mu) = [7.3 +/- 0.8(stat) +/- 0.2(syst)] x 10(-2). In addition, the muonic branching ratios are presented for dominating charm-decay topologies. Normalization of the muonic decays to charged-current interactions provides sigma(mu)-(mu)+/sigma(cc) = [3.16 +/- 0.34(stat) 0.09(syst)] x 10(-3). Selecting only events with visible energy greater than 30 GeV gives a value of (B) over bar (mu) that is less affected by the charm production threshold and quasi-elastic Delta(+)(c) production. Combining this value with the current average of B 12 of vertical bar V-cd vertical bar(LO) = 0. 236 +/- 0.016. (c) 2005 Elsevier B.V. All rights reserved.

The ANTARES neutrino telescope, to be immersed depth in the Mediterranean Sea, will consist of a three-dimensional matrix of 900 large area photomultiplier tubes housed in pressure-resistant glass spheres. The selection of the optimal photomultiplier was a critical step for the project and required an intensive phase of tests and developments carried out in close collaboration with the main manufacturers worldwide. This paper provides an overview of the tests performed by the collaboration and describes in detail the features of the photomultiplier tube chosen for ANTARES.

During the years 1994-1997, the emulsion target of the CHORUS detector was exposed to the wide-band neutrino beam of the CERN SPS of 27 GeV average neutrino energy. In total about 100 000 charged-current neutrino interactions were located in the nuclear emulsion target and fully reconstructed. A high-statistics sample of neutrino interactions with a Do in the final state was collected. Using the decay mode D*(+) -> D-0 pi(+) a production cross-section measurement of the D*+ in neutrinonucleon charged-current interactions was performed. The low Q-value of the decay was used to isolate a sample of candidate events containing a positive hadron with a small PT with respect to the DO direction. A signal of 22.1 +/- 5.5 D*+ events was obtained. The D*(+) production cross-section relative to the D-0 production cross-section, sigma(D*(+))/sigma (D-0), was estimated to be 0.38 +/- 0.09(stat) +/- 0.05(syst). From this result, the fraction of Do's produced via the decay of a D* was deduced to be 0.63 +/- 0.17. The D*(+) production cross-section relative to the nu(mu) charged-current interaction, sigma(D*(+))/sigma(CC), was estimated to be [1.02 +/- 0.25(stat) +/- 0.15(syst)]%. (c) 2005 Elsevier B.V. All rights reserved.