115,385 research outputs found
Symmetry limit properties of a priori mixing amplitudes for non-leptonic and weak radiative decays of hyperons
We show that the so-called parity-conserving amplitudes predicted in the a
priori mixing scheme for non-leptonic and weak radiative decays of hyperons
vanish in the strong-flavor symmetry limit
Building ontologies from folksonomies and linked data: Data structures and Algorithms
We present the data structures and algorithms used in the approach for building domain ontologies from folksonomies and linked data. In this approach we extracts domain terms from folksonomies and enrich them with semantic information from the Linked Open Data cloud. As a result, we obtain a domain ontology that combines the emergent knowledge of social tagging systems with formal knowledge from Ontologies
Structure and electronic properties of molybdenum monoatomic wires encapsulated in carbon nanotubes
Monoatomic chains of molybdenum encapsulated in single walled carbon
nanotubes of different chiralities are investigated using density functional
theory. We determine the optimal size of the carbon nanotube for encapsulating
a single atomic wire, as well as the most stable atomic arrangement adopted by
the wire. We also study the transport properties in the ballistic regime by
computing the transmission coefficients and tracing them back to electronic
conduction channels of the wire and the host. We predict that carbon nanotubes
of appropriate radii encapsulating a Mo wire have metallic behavior, even if
both the nanotube and the wire are insulators. Therefore, encapsulating Mo
wires in CNT is a way to create conductive quasi one-dimensional hybrid
nanostructures.Comment: 8 pages, 10 figure
Improved predictions of the standard model and the detection of new physics in neutron beta decay
We improve the current predictions of the standard model for neutron beta
decay observables and compare them with the currently available ones. Next we
study their implications in the possible detection of new physics. We discuss
where the limitations are and where further efforts should be directed.Comment: 8 pages, 3 figures, to appear in Physics Letters
Destruction of Long-range Order by Quenching the Hopping Range in One Dimension
We study the dynamics in a one dimensional hard-core Bose gas with power-law
hopping after an abrupt reduction of the hopping range using the time-dependent
density-matrix renormalization group (t-DMRG) and bosonization techniques. In
particular, we focus on the destruction of the Bose-Einstein condensate (BEC),
which is present in the initial state in the thermodynamic limit. We argue that
this type of quench is akin to a sudden reduction in the effective
dimensionality of the system (from to ). We identify two
regimes in the evolution of the BEC fraction. For short times the decay of the
BEC fraction is Gaussian while for intermediate to long times, it is well
described by a stretched exponential with an exponent that depends on the
initial effective dimensionality of the system. These results are potentially
relevant for cold trapped-ion experiments which can simulate an equivalent of
hard-core bosons, i.e. spins, with tunable long-range interactions.Comment: 8 pages, 7 figures, accepted for publication in Phys. Rev.
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