4,734 research outputs found
Anomalous transport: a deterministic approach
We introduce a cycle-expansion (fully deterministic) technique to compute the
asymptotic behavior of arbitrary order transport moments. The theory is applied
to different kinds of one-dimensional intermittent maps, and Lorentz gas with
infinite horizon, confirming the typical appearance of phase transitions in the
transport spectrum.Comment: 4 pages, 4 figure
Effects of atomic interactions on Quantum Accelerator Modes
We consider the influence of the inclusion of interatomic interactions on the
delta-kicked accelerator model. Our analysis concerns in particular quantum
accelerator modes, namely quantum ballistic transport near quantal resonances.
The atomic interaction is modelled by a Gross-Pitaevskii cubic nonlinearity,
and we address both attractive (focusing) and repulsive (defocusing) cases. The
most remarkable effect is enhancement or damping of the accelerator modes,
depending on the sign of the nonlinear parameter. We provide arguments showing
that the effect persists beyond mean-field description, and lies within the
experimentally accessible parameter range.Comment: 4 pages, 6 figure
Singular continuous spectra in a pseudo-integrable billiard
The pseudo-integrable barrier billiard invented by Hannay and McCraw [J.
Phys. A 23, 887 (1990)] -- rectangular billiard with line-segment barrier
placed on a symmetry axis -- is generalized. It is proven that the flow on
invariant surfaces of genus two exhibits a singular continuous spectral
component.Comment: 4 pages, 2 figure
The triangle map: a model of quantum chaos
We study an area preserving parabolic map which emerges from the Poincar\' e
map of a billiard particle inside an elongated triangle. We provide numerical
evidence that the motion is ergodic and mixing. Moreover, when considered on
the cylinder, the motion appear to follow a gaussian diffusive process.Comment: 4 pages in RevTeX with 4 figures (in 6 eps-files
Dynamical and transport properties in a family of intermittent area-preserving maps
none3We introduce a family of area-preserving maps representing a (non-trivial) two-dimensional extension of the Pomeau-Manneville family in one dimension. We analyze the long-time behavior of recurrence time distributions and correlations, providing analytical and numerical estimates. We study the transport properties of a suitable lift and use a probabilistic argument to derive the full spectrum of transport moments. Finally the dynamical effects of a stochastic perturbation are considered.noneR. Artuso; L. Cavallasca; G. CristadoroR. Artuso; L. Cavallasca; G. Cristador
The Cleo Rich Detector
We describe the design, construction and performance of a Ring Imaging
Cherenkov Detector (RICH) constructed to identify charged particles in the CLEO
experiment. Cherenkov radiation occurs in LiF crystals, both planar and ones
with a novel ``sawtooth''-shaped exit surface. Photons in the wavelength
interval 135--165 nm are detected using multi-wire chambers filled with a
mixture of methane gas and triethylamine vapor. Excellent pion/kaon separation
is demonstrated.Comment: 75 pages, 57 figures, (updated July 26, 2005 to reflect reviewers
comments), to be published in NIM
The Cleo III Ring Imaging Cherenkov Detector
The CLEO detector has been upgraded to include a state of the art particle
identification system, based on the Ring Imaging Cherenkov Detector (RICH)
technology, in order to take data at the upgraded CESR electron positron
collider. The expected performance is reviewed, as well as the preliminary
results from an engineering run during the first few months of operation of the
CLEO III detector.Comment: 5 pages, 2 Figures Talk given by M. Artuso at 8th Pisa Meeting on
Advanced Detectors, May 200
A Monolithic Time Stretcher for Precision Time Recording
Identifying light mesons which contain only up/down quarks (pions) from those
containing a strange quark (kaons) over the typical meter length scales of a
particle physics detector requires instrumentation capable of measuring flight
times with a resolution on the order of 20ps. In the last few years a large
number of inexpensive, multi-channel Time-to-Digital Converter (TDC) chips have
become available. These devices typically have timing resolution performance in
the hundreds of ps regime. A technique is presented that is a monolithic
version of ``time stretcher'' solution adopted for the Belle Time-Of-Flight
system to address this gap between resolution need and intrinsic multi-hit TDC
performance.Comment: 9 pages, 15 figures, minor corrections made, to appear as JINST_008
Anomalous diffusion and dynamical localization in a parabolic map
We study numerically classical and quantum dynamics of a piecewise parabolic
area preserving map on a cylinder which emerges from the bounce map of
elongated triangular billiards. The classical map exhibits anomalous diffusion.
Quantization of the same map results in a system with dynamical localization
and pure point spectrum.Comment: 4 pages in RevTeX (4 ps-figures included
Bifractality of the Devil's staircase appearing in the Burgers equation with Brownian initial velocity
It is shown that the inverse Lagrangian map for the solution of the Burgers
equation (in the inviscid limit) with Brownian initial velocity presents a
bifractality (phase transition) similar to that of the Devil's staircase for
the standard triadic Cantor set. Both heuristic and rigorous derivations are
given. It is explained why artifacts can easily mask this phenomenon in
numerical simulations.Comment: 12 pages, LaTe
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