6,265 research outputs found
Accuracy Improvement of Real-Time Load-Pull Measurements
This paper describes a new procedure aimed to improve the effectiveness of real-time load-pull calibration. Loadpull measurement accuracy is strongly affected by calibration residual uncertainty. The novel methodology reduces this uncertainty contribution by means of error terms optimization. The proposed method has been tested with simulations and applied to actual measurement data. Considerable improvements have been achieve
On the algebraic structure of rotationally invariant two-dimensional Hamiltonians on the noncommutative phase space
We study two-dimensional Hamiltonians in phase space with noncommutativity
both in coordinates and momenta. We consider the generator of rotations on the
noncommutative plane and the Lie algebra generated by Hermitian rotationally
invariant quadratic forms of noncommutative dynamical variables. We show that
two quantum phases are possible, characterized by the Lie algebras
or according to the relation between the
noncommutativity parameters, with the rotation generator related with the
Casimir operator. From this algebraic perspective, we analyze the spectrum of
some simple models with nonrelativistic rotationally invariant Hamiltonians in
this noncommutative phase space, as the isotropic harmonic oscillator, the
Landau problem and the cylindrical well potential.
PACS: 03.65.-w; 03.65.Fd
MSC: 81R05; 20C35; 22E70Comment: 49 pages. No figures. Version to appear in JP
The bias of cosmic voids in the presence of massive neutrinos
Cosmic voids offer an extraordinary opportunity to study the effects of
massive neutrinos on cosmological scales. Because they are freely streaming,
neutrinos can penetrate the interior of voids more easily than cold dark matter
or baryons, which makes their relative contribution to the mass budget in voids
much higher than elsewhere in the Universe. In simulations it has recently been
shown how various characteristics of voids in the matter distribution are
affected by neutrinos, such as their abundance, density profiles, dynamics, and
clustering properties. However, the tracers used to identify voids in
observations (e.g., galaxies or halos) are affected by neutrinos as well, and
isolating the unique neutrino signatures inherent to voids becomes more
difficult. In this paper we make use of the DEMNUni suite of simulations to
investigate the clustering bias of voids in Fourier space as a function of
their core density and compensation. We find a clear dependence on the sum of
neutrino masses that remains significant even for void statistics extracted
from halos. In particular, we observe that the amplitude of the linear void
bias increases with neutrino mass for voids defined in dark matter, whereas
this trend gets reversed and slightly attenuated when measuring the relative
void-halo bias using voids identified in the halo distribution. Finally, we
argue how the original behaviour can be restored when considering observations
of the total matter distribution (e.g. via weak lensing), and comment on
scale-dependent effects in the void bias that may provide additional
information on neutrinos in the future.Comment: 23 pages, 18 figure
Co-constructing a new framework for evaluating social innovation in marginalized rural areas
The EU funded H2020 project \u2018Social Innovation in Marginalised Rural Areas\u2019 (SIMRA; www.simra-h2020.eu) has the overall objective of advancing the state-of-the-art in social innovation. This paper outlines the process for co- developing an evaluation framework with stakeholders, drawn from across Europe and the Mediterranean area, in the fields of agriculture, forestry and rural development. Preliminary results show the importance of integrating process and outcome-oriented evaluations, and implementing participatory approaches in evaluation practice. They also raise critical issues related to the comparability of primary data in diverse regional contexts and highlight the need for mixed methods approaches in evaluation
The Effect of Promazine Hydrochloride on Anxiety as Measured by the Taylor Manifest Anxiety Scale
Pairing fluctuation effects on the single-particle spectra for the superconducting state
Single-particle spectra are calculated in the superconducting state for a
fermionic system with an attractive interaction, as functions of temperature
and coupling strength from weak to strong. The fermionic system is described by
a single-particle self-energy that includes pairing-fluctuation effects in the
superconducting state. The theory reduces to the ordinary BCS approximation in
weak coupling and to the Bogoliubov approximation for the composite bosons in
strong coupling. Several features of the single-particle spectral function are
shown to compare favorably with experimental data for cuprate superconductors.Comment: 4 pages, 4 figure
GRB 081024B and GRB 140402A: two additional short GRBs from binary neutron star mergers
Theoretical and observational evidences have been recently gained for a
two-fold classification of short bursts: 1) short gamma-ray flashes (S-GRFs),
with isotropic energy ~erg and no BH formation, and 2) the
authentic short gamma-ray bursts (S-GRBs), with isotropic energy
~erg evidencing a BH formation in the binary neutron star
merging process. The signature for the BH formation consists in the on-set of
the high energy (--~GeV) emission, coeval to the prompt emission, in
all S-GRBs. No GeV emission is expected nor observed in the S-GRFs. In this
paper we present two additional S-GRBs, GRB 081024B and GRB 140402A, following
the already identified S-GRBs, i.e., GRB 090227B, GRB 090510 and GRB 140619B.
We also return on the absence of the GeV emission of the S-GRB 090227B, at an
angle of from the \textit{Fermi}-LAT boresight. All the correctly
identified S-GRBs correlate to the high energy emission, implying no
significant presence of beaming in the GeV emission. The existence of a common
power-law behavior in the GeV luminosities, following the BH formation, when
measured in the source rest-frame, points to a commonality in the mass and spin
of the newly-formed BH in all S-GRBs.Comment: 16 pages, submitted to ApJ, second version addressing the comments by
the refere
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