4,609 research outputs found
KM3NeT: Towards a km3 Mediterranean Neutrino Telescope
The observation of high-energy extraterrestrial neutrinos is one of the most
promising future options to increase our knowledge on non-thermal processes in
the universe. Neutrinos are e.g. unavoidably produced in environments where
high-energy hadrons collide; in particular this almost certainly must be true
in the astrophysical accelerators of cosmic rays, which thus could be
identified unambiguously by sky observations in "neutrino light". To establish
neutrino astronomy beyond the detection of single events, neutrino telescopes
of km3 scale are needed. In order to obtain full sky coverage, a corresponding
detector in the Mediterranean Sea is required to complement the IceCube
experiment currently under construction at the South Pole. The groups pursuing
the current neutrino telescope projects in the Mediterranean Sea, ANTARES, NEMO
and NESTOR, have joined to prepare this future installation in a 3-year,
EU-funded Design Study named KM3NeT. This report will highlight some of the
physics issues to be addressed with the KM3NeT detector and will outline the
path towards its realisation, with a focus on the upcoming Design Study.Comment: Presented at VLVnT2 Workshop, Catania, Siciliy, Italy, 8-11 Nov 200
High-Energy Neutrino Astronomy: A Glimpse of the Promised Land
In 2012, physicists and astronomers celebrated the hundredth anniversary of
the detection of cosmic rays by Viktor Hess. One year later, in 2013, there was
first evidence for extraterrestrial high-energy neutrinos, i.e. for signal
which may contain key information on the origin of cosmic rays. That evidence
is provided by data taken with the IceCube neutrino telescope at the South
Pole. First concepts to build a detector of this kind have been discussed at
the 1973 International Cosmic Ray Conference. Nobody would have guessed at that
time that the march towards first discoveries would take forty years, the
biblical time of the march from Egypt to Palestine. But now, after all, the
year 2013 has provided us a first glimpse to the promised land of the neutrino
universe at highest energies. This article sketches the evolution towards
detectors with a realistic discovery potential, describes the recent relevant
results obtained with the IceCube and ANTARES neutrino telescopes and tries a
look into the future.Comment: 19 pages, 16 figures. Talk given at the session of the Russian
Academy of Science dedicated to Bruno Pontecorvo, Dubna, Sept. 201
Commercial Applications Multispectral Sensor System
NASA's Office of Commercial Programs is funding a multispectral sensor system to be used in the development of remote sensing applications. The Airborne Terrestrial Applications Sensor (ATLAS) is designed to provide versatility in acquiring spectral and spatial information. The ATLAS system will be a test bed for the development of specifications for airborne and spaceborne remote sensing instrumentation for dedicated applications. This objective requires spectral coverage from the visible through thermal infrared wavelengths, variable spatial resolution from 2-25 meters; high geometric and geo-location accuracy; on-board radiometric calibration; digital recording; and optimized performance for minimized cost, size, and weight. ATLAS is scheduled to be available in 3rd quarter 1992 for acquisition of data for applications such as environmental monitoring, facilities management, geographic information systems data base development, and mineral exploration
High-Energy Neutrino Astronomy: where do we stand, where do we go?
With the identification of a diffuse flux of astrophysical ("cosmic")
neutrinos in the TeV-PeV energy range, IceCube has opened a new window to the
Universe. However, the corresponding cosmic landscape is still uncharted: so
far, the observed flux does not show any clear association with known source
classes. In the present talk, I sketch the way from Baikal-NT200 to IceCube and
summarize IceCube's recent astrophysics results. Finally, I describe the
present projects to build even larger detectors: GVD in Lake Baikal, KM3NeT in
the Mediterranean Sea and IceCube-Gen2 at the South Pole. These detectors will
allow studying the high-energy neutrino sky in much more detail than the
present arrays permit.Comment: Talk given at the occasion of the 50th anniversary of the Baksan
Laborator
Planarization and fabrication of bridges across deep groves or holes in silicon using a dry film photoresist followed by an etch back
A technique is presented that provides planarization after a very deep etching step in silicon. This offers the possibility for not only resist spinning and layer patterning but also for realization of bridges and cantilevers across deep grooves or holes. The technique contains a standard dry film lamination step to cover a wafer with a 38 mu m thick foil. Next the foil is etched back to the desired thickness of a few micrometres. This thin film facilitates resist spinning and high-resolution patterning. The planarization method is demonstrated by the fabrication of aluminium bridges across a deep groove in silicon
Neutrino Telescopy in the Mediterranean Sea
The observation of high-energy extraterrestrial neutrinos is one of the most
promising future options to increase our knowledge on non-thermal processes in
the universe. Neutrinos are e.g. unavoidably produced in environments where
high-energy hadrons collide; in particular this almost certainly must be true
in the astrophysical accelerators of cosmic rays, which thus could be
identified unambiguously by sky observations in "neutrino light". On the one
hand, neutrinos are ideal messengers for astrophysical observations since they
are not deflected by electromagnetic fields and interact so weakly that they
are able to escape even from very dense production regions and traverse large
distances in the universe without attenuation. On the other hand, their weak
interaction poses a significant problem for detecting neutrinos. Huge target
masses up to gigatons must be employed, requiring to instrument natural
abundances of media such as sea water or antarctic ice. The first generation of
such neutrino telescopes is taking data or will do so in the near future, while
the second-generation projects with cubic-kilometre size is under construction
or being prepared. This report focuses on status and prospects of current
(ANTARES, NEMO, NESTOR) and future (KM3NeT) neutrino telescope projects in the
Mediterranean Sea.Comment: Presented at 27th Int. School on Nucl. Phys. (Neutrinos in Cosmology,
in Astro, Particle and Nuclear Physics), Erice/Italy, Sept. 2005; 8 pages, 7
figures. To appear in Prog. Part. Nucl. Phys. V2,V3: fixed incompatibilities
of postscript figures with the arXiv softwar
Membranes fabricated with a deep single corrugation for package stress reduction and residual stress relief
Thin square membranes including a deep circular corrugation are realized and tested for application in a strain-based pressure sensor. Package-induced stresses are reduced and relief of the residual stress is obtained, resulting in a large pressure sensitivity and a reduced temperature sensitivity. Finite element method simulations were carried out, showing that the pressure-deflection behaviour of the structure is close to that of a circular membrane with clamped edge but free radial motion
Diffractive production at small in future Electron - Ion Colliders
The future Electron - Ion () Collider is expected to probe the high
energy regime of the QCD dynamics, with the exclusive vector meson production
cross section being one of the most promising observables. In this paper we
complement previous studies of exclusive processes presenting a comprehensive
analysis of diffractive production at small . We compute the coherent
and incoherent cross sections taking into account non-linear QCD dynamical
effects and considering different models for the dipole - proton scattering
amplitude and for the vector meson wave function. The dependence of these cross
sections with the energy, photon virtuality, nuclear mass number and squared
momentum transfer is analysed in detail. Moreover, we compare the non-linear
predictions with those obtained in the linear regime. Finally, we also estimate
the exclusive photon, and production and compare with the
results obtained for production. Our results demonstrate that the
analysis of diffractive production in future electron - ion colliders
will be important to understand the non-linear QCD dynamics.Comment: 12 pages, 8 figures, 1 table. Enlarged and revised version to be
published in the Journal of Physics G. arXiv admin note: text overlap with
arXiv:1503.0064
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