The Antarctic Muon And Neutrino Detector Array (Amanda) is a high-energy neutrino telescope. It is a lattice of optical modules (OM) installed in the clear ice below the South Pole Station. Each OM contains a photomultiplier tube (PMT) that detects photons of Cherenkov light generated in the ice by muons and electrons. IceCube is a cubic-kilometer-sized expansion of Amanda currently being built at the South Pole. In IceCube the PMT signals are digitized already in the optical modules and transmitted to the surface. A prototype string of 41 OMs equipped with this new all-digital technology was deployed in the Amanda array in the year 2000. In this paper we describe the technology and demonstrate that this string serves as a proof of concept for the IceCube array. Our investigations show that the OM timing accuracy is 5ns. Atmospheric muons are detected in excellent agreement with expectations with respect to both angular distribution and absolute rate.

LAERTIS, designed to collect environmental data from the deep-sea, is operated since 1999 and has been deployed several time at 4000m depth at the NESTOR site. Power and data were transferred through a 30-km electro-optical cable to the Shore Station. In this report, we describe briefly the LAERTIS instrumentation and present typical data that were collected successfully during those deployment demonstrating the importance of a deep-sea station permanently connected to shore.

The A ntarctic M uon A nd N eutrino D etector A rray (A MANDA ) is a high-energy neutrino telescope. It is a lattice of optical modules (OM) installed in the clear ice below the South Pole Station. Each OM contains a photomultiplier tube (PMT) that detects photons of Cherenkov light generated in the ice by muons and electrons. I CE C UBE is a cubic-kilometer-sized expansion of A MANDA currently being built at the South Pole. In I CE C UBE the PMT signals are digitized already in the optical modules and transmitted to the surface. A prototype string of 41 OMs equipped with this new all-digital technology was deployed in the A MANDA array in the year 2000. In this paper we describe the technology and demonstrate that this string serves as a proof of concept for the I CE C UBE array. Our investigations show that the OM timing accuracy is 5 ns. Atmospheric muons are detected in excellent agreement with expectations with respect to both angular distribution and absolute rate.

The AntarcticMuon And NeutrinoDetectorArray (AMANDA ) is a high-energy neutrino telescope. It is a lattice of optical modules (OM) installed in the clear ice below the South Pole Station. Each OM contains a photomultiplier tube (PMT) that detects photons of Cherenkov light generated in the ice by muons and electron s. ICECUBE is a cubickilometer-sized expansion of A MANDA currently being built at the South Pole. In I CECUBE the PMT signals are digitized already in the optical modules and transmitted to the surface. A prototype string of 41 OMs equipped with this new a ll-digital technology was deployed in the AMANDA array in the year 2000. In this paper we describe the technolo gy and demonstrate that this string serves as a proof of concept for the ICECUBE array. Our investigations show that the OM timing accuracy is 5 ns. Atmo spheric muons are detected in excellent agreement with expectations with respect to bo th angular distribution and absolute rate.

The key component of NESTOR, the deep-sea Cherenkov neutrino telescope, built in the Mediterranean, NW of Greece, is the optical module. The NESTOR Optical Module employs a PhotoMultiplier Tube (PMT) in a transparent glass pressure housing. The Hamamatsu PMT R8055-01, 13in. photomultiplier was selected for NESTOR to replace the old 15′′ Hamamatsu PMTs (R2018-03). Extensive tests have been made on the sensitivity, uniformity, time resolution and noise rates of 162 R8055-01 13in. PMTs

A module of the NESTOR underwater neutrino telescope, was deployed, in March 2003, at a depth of 3800m in order to test the overall detector performance and particularly that of the data acquisition systems. A prolonged period of running under stable operating conditions made it possible to measure the cosmic ray muon flux, I0cosa(θ).

NESTOR is a deep-sea neutrino telescope that is under construction in the Ionian Sea off the coast of Greece at a depth of about 4000m. This paper briefly reviews the detector structure and deployment techniques before describing in detail the calibration and engineering run of a test detector carried out in 2003. The detector was operated for more than 1 month and data was continuously transmitted to shore via an electro-optical cable laid on the sea floor. The performance of the detector is discussed and analysis of the data obtained shows that the measured cosmic ray muon flux is in good agreement with previous measurements and with phenomenological cosmic ray models.

NESTOR is a deep-sea neutrino telescope that is currently under construction in the Ionian Sea, off the coast of Pylos, Southwestern Greece, at a depth of approximately 4000 m. We outline briefly the layout of the telescope and summarize the present status of the project. The results of a one month continuous operation of a test unit using our standard detector modules is discussed. Data of the cosmic ray muon flux acquired with the help of an electro-optical cable during this period is presented. The data are in good agreement with earlier experiments at comparable, depth. In addition we discuss our results of bioluminescence measurements and other site and technical aspects.

A module of the NESTOR underwater neutrino telescope was deployed at a depth of 3800 m in order to test the overall detector performance and particularly that of the data acquisition systems. A prolonged period of running under stable operating conditions made it possible to measure the cosmic ray muon flux, I-0 (.) cos(alpha)(theta), as a function of the zenith angle theta. Measured values of index alpha and the vertical intensity I-0(Graphics)are in good agreement with previous measurements and phenomenological predictions. (c) 2005 Elsevier B.V. All rights reserved.

A module of the NESTOR underwater neutrino telescope was deployed at a depth of 3800 m in order to test the overall detector performance and particularly that of the data acquisition systems. A prolonged period of running under stable operating conditions made it possible to measure the cosmic ray muon flux, I0 cosðhÞ, as a function of the zenith angle h. Measured values of index a and the vertical intensity I0 0927-6505/$ see front matter 2005 Elsevier B.V. All rights reserved. doi:10.1016/j.astropartphys.2005.02.001 * Corresponding author. Tel./fax: +30 210 7276948. E-mail address: eanason@cc.uoa.gr (E.G. Anassontzis). ðsystÞ cm 2 s 1 sr 1 378 G. Aggouras et al. / Astroparticle Physics 23 (2005) 377–392 a 1⁄4 4:7 0:5ðstatÞ 0:2ðsystÞ I0 1⁄4 9:0 10 9 0:7 10 ðstatÞ 0:4 10 are in good agreement with previous measurements and phenomenological predictions. 2005 Elsevier B.V. All rights reserved. PACS: 95.55.Vj; 29.40.Ka; 13.15.+g

NESTOR is a submarine high-energy muon and neutrino telescope, now under construction for deployment in the Mediterranean close to Greek shores. The first floor of NESTOR with 12 optical modules was deployed successfully in March 2003 together with the electronics system. All systems and the associated environmental monitoring units are operating properly and data are being recorded. The status of the NESTOR project is presented. We outline briefly the construction of the deepwater neutrino telescope, properties of the NESTOR site, infrastructure of the project, the deployment of the first floor, and its current operation. The first data are presented and plans for the next steps are summarized.

NESTOR is a submarine high-energy muon and neutrino telescope, now under construction for deployment in the Mediterranean close to Greek shores. The first floor of the NESTOR with 12 optical modules had been deployed successfully in March 2003 together with electronics system. All systems and the associated environmental monitoring units are operating properly and data are being recorded. The status of the NESTOR project is presented. We outline briefly the construction of deepwater neutrino telescope, properties of the NESTOR site, infrastructure of the project, the deployment of the first floor and its current operation. First data are presented and plans for next steps are summarized.

The first so-called floor with 12 detector modules of the NESTOR deep sea high energy muon and neutrino telescope had been deployed successfully this March (2003) together with its electronics system. Since that data the system and the associated environmental monitoring units are operating properly and data pp. 1377–1380 c ©2003 by Universal Academy Press, Inc.

Recently, a reduction in the incidence of pristane-induced plasmacytomas in BALB/cAnPt (BALB/c) mice that were kept in viral specific pathogen-free (SPF) conditions has been reported. Environmentally, these BALB/c mice differed from conventionally-housed (CON) mice only in viral exposure and diet (i.e. sterilization of mouse chow), since microbial colonization of the intestinal tract was seen to be equivalent. This report assessed the ability of SPF- and CON-BALB/c mice to respond to immunologic challenge with soluble antigen, i.e. hen egg white lyzosyme (HEL), as a means of evaluating differences in T and B cell function and, indirectly, evaluating the possible effects these differences might have on plasmacytoma development. When cultured in vitro for 5 days with HEL, HEL-primed lymph node cells (LNC) from BALB/c mice proliferated to a significantly lesser extent than HEL-primed CON-BALB/c LNC. Moreover, HEL-induced production of IFN-γ and IL-5 was significantly lower in SPF LNC. Serum IgG1 levels were 10-fold lower in -BALB/c mice with, or without prior immunization with HEL and were not reconstituted by repeated injections of HEL in adjuvant. Serum IgM levels of SPF- and CON-BALB/c mice were equivalent. This reduction in immune responses could not be attributed to a lack of colonization of secondary lymphoid organs, since flow cytometric analysis of LNC revealed no difference in the number of recoverable cells and the proportion of lymphocyte subsets (CD4+, CD8+ and CD45− cells) obtained from SPF- and CON-BALB/c mice. However, only CON LNC were induced to increase surface expression of CD44 after antigenic or mitogenic stimulation in vitro. Antibody responsiveness to HEL, as evidenced by serum anti-HEL binding or splenic hybridoma studies, demonstrated higher levels of IgG1 antibodies in CON-BALB/c mice than in SPF mice. However, a greater proportion of the SPF IgG1 antibodies present were specifically directed against HEL, so that specific activity was greater in SPF-BALB/c mice. Therefore, while SPF-BALB/c mice have a more restricted response to HEL than CON-BALB/c mice, those antibodies that are produced are more specifically directed against HEL with very little apparent bystander/polyclonal activation of multireactive cells. Resistance to plasmacytomas in SPF-BALB/c mice, therefore, may stem from a reduced number of circulating memory T and B cells, which are capable of reacting and/or crossreacting with a chronic inflammatory stimulus.