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We present Atacama Compact Array and Atacama Pathfinder Experiment observations of the [N  ii ] 205 μm fine-structure line in 40 sub-millimetre galaxies lying at redshifts z  = 3–6, drawn from the 2500 deg2 South Pole Telescope survey. This represents the largest uniformly selected sample of high-redshift [N  ii ] 205 μm measurements to date. 29 sources also have [C  ii ] 158 μm line observations allowing a characterization of the distribution of the [C  ii ] to [N  ii ] luminosity ratio for the first time at high redshift. The sample exhibits a median L |$_{{\rm{[C\,{\small II}]}}}$| / L |$_{{\rm{[N\,{\small II}]}}}$| ≈ 11.0 and interquartile range of 5.0 –24.7. These ratios are similar to those observed in local (Ultra)luminous infrared galaxies (LIRGs), possibly indicating similarities in their interstellar medium. At the extremes, we find individual sub-millimetre galaxies with L |$_{{\rm{[C\,{\small II}]}}}$| / L |$_{{\rm{[N\,{\small II}]}}}$| low enough to suggest a smaller contribution from neutral gas than ionized gas to the [C  ii ] flux and high enough to suggest strongly photon or X-ray region dominated flux. These results highlight a large range in this line luminosity ratio for sub-millimetre galaxies, which may be caused by variations in gas density, the relative abundances of carbon and nitrogen, ionization parameter, metallicity, and a variation in the fractional abundance of ionized and neutral interstellar medium. [ABSTRACT FROM AUTHOR]

The ANTARES collaboration is constructing a neutrino telescope in the Mediterranean Sea at a depth of 2400 metres, about 40 kilometres off the French coast near Toulon. The detector will consist of 12 vertical strings anchored at the sea bottom, each supporting 25 triplets of optical modules equipped with photomultipliers, yielding sensitivity to neutrinos with energies above some 10 GeV. The effective detector area is roughly 0.1 km2 for neutrino energies exceeding 10 TeV. The measurement of the Čerenkov light emitted by muons produced in muon-neutrino charged-current interactions in water and under-sea rock will permit the reconstruction of the neutrino direction with an accuracy of better than 0.3∘ at high energies. ANTARES will complement the field of view of neutrino telescopes at the South Pole in the low-background searches for point-sources of high-energy cosmic neutrinos and will also be sensitive to neutrinos produced by WIMP annihilation in the Sun or the Galactic centre. PACS: 95.55.Vj Neutrino, muon, pion, and other elementary particle detectors; cosmic ray detectors – 95.35.+d Dark matter (stellar, interstellar, galactic, and cosmological) – 95.30.-k Fundamental aspects of astrophysics [ABSTRACT FROM AUTHOR]

Abstract: The Milagro detector has identified several TeV gamma-ray sources with fluxes consistent with typical cosmic-ray generating supernova remnants interacting with the interstellar medium. In this contribution we show that IceCube, a kilometer-scale neutrino detector under construction at the South Pole, can provide incontrovertible evidence of cosmic-ray acceleration in these sources by detecting neutrinos. The sensitivity is maximal if only events with energies above about 40TeV are considered where the atmospheric neutrino background is largely reduced. [Copyright &y& Elsevier]