181 research outputs found
Political Elites in Federalized Countries: The Case of Spain (1980-2005). CES Working Paper, no. 146, 2008
This paper explores the social profile of the regional elite that has emerged in Spain since the de-mocratization and federalization of the country. For the first time, researchers present data about crucial variables like gender, place of birth, age, education, and profession. They make inter-regional comparisons, put their data on an international perspective, and try to explain some un-expected findings, such as the behavior of political elites in Catalonia and Castile-La Mancha. The authors compare also the social profile of MPs of the two largest parties and show that the gap between society and political elite has been reduced over the years. The paper offers a research agenda
Precise determination of the structure factor and contact in a unitary Fermi gas
We present a high-precision determination of the universal contact parameter
in a strongly interacting Fermi gas. In a trapped gas at unitarity we find the
contact to be at a temperature of 0.08 of the Fermi temperature
in a harmonic trap. The contact governs the high-momentum (short-range)
properties of these systems and this low temperature measurement provides a new
benchmark for the zero temperature homogeneous contact. The experimental
measurement utilises Bragg spectroscopy to obtain the dynamic and static
structure factors of ultracold Fermi gases at high momentum in the unitarity
and molecular Bose-Einstein condensate (BEC) regimes. We have also performed
quantum Monte Carlo calculations of the static properties, extending from the
weakly coupled Bardeen-Cooper-Schrieffer (BCS) regime to the strongly coupled
BEC case, which show agreement with experiment at the level of a few percent.Comment: Replaced with accepted versio
Weak Lensing of the CMB by Large-Scale Structure
Several recent papers have studied lensing of the CMB by large-scale
structures, which probes the projected matter distribution from to
. This interest is motivated in part by upcoming high resolution,
high sensitivity CMB experiments, such as APEX/SZ, ACT, SPT or Planck, which
should be sensitive to lensing. In this paper we examine the reconstruction of
the large-scale dark matter distribution from lensed CMB temperature
anisotropies. We go beyond previous work in using numerical simulations to
include higher order, non-Gaussian effects and study how well the quadratic
estimator of \cite{Hu01a} is able to recover the input field. We also study
contamination by kinetic Sunyaev-Zel'dovich signals, which is spectrally
indistinguishable from lensed CMB anisotropies. We finish by estimating the
sensitivity of the previously cited experiments.Comment: 26 pages, 13 figures, replaced to match the minor revisions of the
accepted versio
Potential sources of contamination to weak lensing measurements: constraints from N-body simulations
We investigate the expected correlation between the weak gravitational shear
of distant galaxies and the orientation of foreground galaxies, through the use
of numerical simulations. This shear-ellipticity correlation can mimic a
cosmological weak lensing signal, and is potentially the limiting physical
systematic effect for cosmology with future high-precision weak lensing
surveys. We find that, if uncorrected, the shear-ellipticity correlation could
contribute up to 10% of the weak lensing signal on scales up to 20 arcminutes,
for lensing surveys with a median depth z=1. The most massive foreground
galaxies are expected to cause the largest correlations, a result also seen in
the Sloan Digital Sky Survey. We find that the redshift dependence of the
effect is proportional to the lensing efficiency of the foreground, and this
offers prospects for removal to high precision, although with some model
dependence. The contamination is characterised by a weakly negative B-mode,
which can be used as a diagnostic of systematic errors. We also provide more
accurate predictions for a second potential source of error, the intrinsic
alignment of nearby galaxies. This source of contamination is less important,
however, as it can be easily removed with distance information.Comment: 12 pages, 10 figures. Version accepted by MNRA
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