281 research outputs found
Neutrino oscillation physics at an upgraded CNGS with large next generation liquid Argon TPC detectors
The determination of the missing element (magnitude and phase) of
the PMNS neutrino mixing matrix is possible via the detection of \numu\to\nue
oscillations at a baseline and energy given by the atmospheric
observations, corresponding to a mass squared difference . While the current optimization of the CNGS
beam provides limited sensitivity to this reaction, we discuss in this document
the physics potential of an intensity upgraded and energy re-optimized CNGS
neutrino beam coupled to an off-axis detector. We show that improvements in
sensitivity to compared to that of T2K and NoVA are possible with
a next generation large liquid Argon TPC detector located at an off-axis
position (position rather distant from LNGS, possibly at shallow depth). We
also address the possibility to discover CP-violation and disentangle the mass
hierarchy via matter effects. The considered intensity enhancement of the CERN
SPS has strong synergies with the upgrade/replacement of the elements of its
injector chain (Linac, PSB, PS) and the refurbishing of its own elements,
envisioned for an optimal and/or upgraded LHC luminosity programme.Comment: 37 pages, 20 figure
Effects of zinc on leaf decomposition by fungi in streams : studies in microcosms
The effect of zinc on leaf decomposition by aquatic fungi was studied in microcosms. Alder leaf disks were precolonized for 15 days at the source of the Este River, and exposed to different zinc concentrations during 25 days. Leaf mass loss, fungal biomass (based on ergosterol concentration), fungal production (rates of [1-14C]acetate incorporation into ergosterol), sporulation rates and species richness of aquatic hyphomycetes were determined. At the source of the Este River decomposition of alder leaves was fast and 50% of the initial mass was lost in 25 days. A total of 18 aquatic hyphomycete species were recorded during 42 days of leaf immersion. Articulospora tetracladia was the dominant species, followed by Lunulospora curvula and two unidentified species with sigmoid conidia. Cluster analysis suggested that zinc concentration and exposure time affected the structure of aquatic hyphomycete assemblages, even though richness had not been severely affected. Both zinc concentration and exposure time significantly affected leaf mass loss, fungal production and sporulation, but not fungal biomass. Zinc exposure reduced leaf mass loss, inhibited fungal production and affected fungal reproduction by either stimulating or inhibiting sporulation rates. The results of this work suggested zinc pollution might depress leaf decomposition in streams due to changes in the structure and activity of aquatic fungi.Fundação para a Ciência e a Tecnologia (FCT) – Programa Operacional “Ciência, Tecnologia, Inovação” (POCTI) - POCTI/34024/BSE/2000
An Experimental Area for Short Baseline Neutrino Physics on the CERN Neutrino Beam to Gran Sasso
A new neutrino beam line from the CERN SPS to the Gran Sasso laboratory in Italy is presently under study. The new neutrino beam will allow both long baseline and short baseline neutrino oscillation experiments to be performed. This report presents a conceptual design of the short baseline experimental area to be located at a distance of 1858 m from the neutrino target
Underground Neutrino Detectors for Particle and Astroparticle Science: the Giant Liquid Argon Charge Imaging ExpeRiment (GLACIER)
The current focus of the CERN program is the Large Hadron Collider (LHC),
however, CERN is engaged in long baseline neutrino physics with the CNGS
project and supports T2K as recognized CERN RE13, and for good reasons: a
number of observed phenomena in high-energy physics and cosmology lack their
resolution within the Standard Model of particle physics; these puzzles include
the origin of neutrino masses, CP-violation in the leptonic sector, and baryon
asymmetry of the Universe. They will only partially be addressed at LHC. A
positive measurement of would certainly give a
tremendous boost to neutrino physics by opening the possibility to study CP
violation in the lepton sector and the determination of the neutrino mass
hierarchy with upgraded conventional super-beams. These experiments (so called
``Phase II'') require, in addition to an upgraded beam power, next generation
very massive neutrino detectors with excellent energy resolution and high
detection efficiency in a wide neutrino energy range, to cover 1st and 2nd
oscillation maxima, and excellent particle identification and
background suppression. Two generations of large water Cherenkov
detectors at Kamioka (Kamiokande and Super-Kamiokande) have been extremely
successful. And there are good reasons to consider a third generation water
Cherenkov detector with an order of magnitude larger mass than Super-Kamiokande
for both non-accelerator (proton decay, supernovae, ...) and accelerator-based
physics. On the other hand, a very massive underground liquid Argon detector of
about 100 kton could represent a credible alternative for the precision
measurements of ``Phase II'' and aim at significantly new results in neutrino
astroparticle and non-accelerator-based particle physics (e.g. proton decay).Comment: 31 pages, 14 figure
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