32,515 research outputs found
Chaotic behavior of the Compound Nucleus, open Quantum Dots and other nanostructures
It is well established that physical systems exhibit both ordered and chaotic
behavior. The chaotic behavior of nanostructure such as open quantum dots has
been confirmed experimentally and discussed exhaustively theoretically. This is
manifested through random fluctuations in the electronic conductance. What
useful information can be extracted from this noise in the conductance? In this
contribution we shall address this question. In particular, we will show that
the average maxima density in the conductance is directly related to the
correlation function whose characteristic width is a measure of energy- or
applied magnetic field- correlation length. The idea behind the above has been
originally discovered in the context of the atomic nucleus, a mesoscopic
system. Our findings are directly applicable to graphene.Comment: 10 pages, 5 figures. Contribution to: "4th International Workshop on
Compound-Nuclear Reactions and Related Topics (CNR*13)", October 7-11, 2013,
Maresias, Brazil. To appear in the proceeding
Mid-Infrared Observations of Planetary Nebulae detected in the GLIMPSE 3D Survey
We present mapping, profiles and photometry for 24 planetary nebulae (PNe)
detected in the GLIMPSE 3D mid-infrared (MIR) survey of the Galactic plane. The
PNe show many of the properties observed in previous studies of these sources,
including evidence for longer wave emission from outside of the ionised zones,
a likely consequence of emission from polycyclic aromatic hydrocarbons (PAHs)
within the nebular photo-dissociation regimes (PDRs). We also note variations
in 5.8/4.5 and 8.0/4.5 microns flux ratios with distance from the nuclei;
present evidence for enhanced MIR emission in the halos of the sources; and
note evidence for variations in colour with nebular evolution.Comment: 35 pages, 28 figures, Accepted for publication in Revista Mexicana de
Astronomia y Astrofisica (RevMexAA). 61 pages in arXi
Hamming distance and mobility behavior in generalized rock-paper-scissors models
This work reports on two related investigations of stochastic simulations
which are widely used to study biodiversity and other related issues. We first
deal with the behavior of the Hamming distance under the increase of the number
of species and the size of the lattice, and then investigate how the mobility
of the species contributes to jeopardize biodiversity. The investigations are
based on the standard rules of reproduction, mobility and predation or
competition, which are described by specific rules, guided by generalization of
the rock-paper-scissors game, valid in the case of three species. The results
on the Hamming distance indicate that it engenders universal behavior,
independently of the number of species and the size of the square lattice. The
results on the mobility confirm the prediction that it may destroy diversity,
if it is increased to higher and higher values.Comment: 7 pages, 9 figures. To appear in EP
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