12,374 research outputs found
Scene-based nonuniformity correction with video sequences and registration
We describe a new, to our knowledge, scene-based nonuniformity correction algorithm for array detectors. The algorithm relies on the ability to register a sequence of observed frames in the presence of the fixed-pattern noise caused by pixel-to-pixel nonuniformity. In low-to-moderate levels of nonuniformity, sufficiently accurate registration may be possible with standard scene-based registration techniques. If the registration is accurate, and motion exists between the frames, then groups of independent detectors can be identified that observe the same irradiance (or true scene value). These detector outputs are averaged to generate estimates of the true scene values. With these scene estimates, and the corresponding observed values through a given detector, a curve-fitting procedure is used to estimate the individual detector response parameters. These can then be used to correct for detector nonuniformity. The strength of the algorithm lies in its simplicity and low computational complexity. Experimental results, to illustrate the performance of the algorithm, include the use of visible-range imagery with simulated nonuniformity and infrared imagery with real nonuniformity
Spontaneous alloying in binary metal microclusters - A molecular dynamics study -
Microcanonical molecular dynamics study of the spontaneous alloying(SA),
which is a manifestation of fast atomic diffusion in a nano-sized metal
cluster, is done in terms of a simple two dimensional binary Morse model.
Important features observed by Yasuda and Mori are well reproduced in our
simulation. The temperature dependence and size dependence of the SA phenomena
are extensively explored by examining long time dynamics. The dominant role of
negative heat of solution in completing the SA is also discussed. We point out
that a presence of melting surface induces the diffusion of core atoms even if
they are solid-like. In other words, the {\it surface melting} at substantially
low temperature plays a key role in attaining the SA.Comment: 15 pages, 12 fgures, Submitted to Phys.Rev.
Neutrino Scattering on Glass: NuSOnG
These proceedings describe the physics goals and initial design for a new
experiment: NuSOnG -- Neutrino Scattering On Glass. The design will yield about
two orders of magnitude higher statistics than previous high energy neutrino
experiments, observed in a detector optimized for low hadronic energy and
electromagnetic events. As a result, the purely weak processes and (inverse muon decay)
can be measured with high accuracy for the first time. This allows important
precision electroweak tests and well as direct searches for new physics. The
high statistics also will yield the world's largest sample of Deep Inelastic
(DIS) events for precision parton distribution studies.Comment: Proceedings of NuFact0
MANX: A 6D Ionization-Cooling Experiment
Six-dimensional ionization cooling of muons is essential for muon colliders
and possibly beneficial for neutrino factories. An experiment to demonstrate
six-dimensional ionization cooling using practical apparatus is presented. It
exploits recent innovative ideas that may lead to six-dimensional muon-cooling
channels with emittance reduction approaching that needed for high-luminosity
muon colliders.Comment: 3 pages, 4 figures, to appear in Proceedings of the 9th International
Workshop on Neutrino Factories, Superbeams, and Betabeams (NuFact07), August
6-11, 2007, Okayama University, Japa
Nuclear effects in Neutrino Nuclear Cross-sections
Nuclear effects in the quasielastic and inelastic scattering of
neutrinos(antineutrinos) from nuclear targets have been studied. The
calculations are done in the local density approximation which take into
account the effect of nucleon motion as well as renormalisation of weak
transition strengths in the nuclear medium. The inelastic reaction leading to
production of pions is calculated in a dominance model taking into
account the renormalization of properties in the nuclear medium.Comment: 4 pages,3 figures, Ninth International Workshop on Neutrino
Factories, Superbeams and Betabeams (NuFact07), August 6-11, 2007, Okayama
University, Okayama, Japa
Chiral Symmetry and Neutrino Pion Production off the Nucleon
The neutrino pion production off the nucleon is traditionally described in
the literature by means of the weak excitation of the Delta(1232) resonance and
its subsequent decay into N pi. Here, we present results from a model that
includes also some background terms required by chiral symmetry. We show that
the contribution of these terms is sizeable and leads to significant effects in
total and partially integrated pion production cross sections at intermediate
energies of interest for neutrino oscillation experiments. Finally, we discuss
parity-violating contributions to the pion angular differential cross section
induced by the interference of these non-resonant terms with the Delta piece.Comment: To appear in the proceedings of 9th International Workshop On
Neutrino Factories, Superbeams and Betabeams (NuFact07) August 6-11, 2007,
Okayama University, Japa
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