31,183 research outputs found
Thermal entanglement witness for materials with variable local spin lengths
We show that the thermal entanglement in a spin system using only magnetic
susceptibility measurements is restricted to the insulator materials. We
develop a generalization of the thermal entanglement witness that allows us to
get information about the system entanglement with variable local spin lengths
that can be used experimentally in conductor or insulator materials. As an
application, we study thermal entanglement for the half-filled Hubbard model
for linear, square and cubic clusters. We note that it is the itinerancy of
electrons that favors the entanglement. Our results suggest a weak dependence
between entanglement and external spin freedom degrees.Comment: 4 pages, 3 figure
Analytical Multi-kinks in smooth potentials
In this work we present an approach which can be systematically used to
construct nonlinear systems possessing analytical multi-kink profile
configurations. In contrast with previous approaches to the problem, we are
able to do it by using field potentials which are considerably smoother than
the ones of Doubly Quadratic family of potentials. This is done without losing
the capacity of writing exact analytical solutions. The resulting field
configurations can be applied to the study of problems from condensed matter to
brane world scenarios
GLADE: A galaxy catalogue for multimessenger searches in the advanced gravitational-wave detector era
We introduce a value-added full-sky catalogue of galaxies, named as Galaxy List for the Advanced Detector Era, or GLADE. The purpose of this catalogue is to (i) help identifications of host candidates for gravitational-wave events, (ii) support target selections for electromagnetic follow-up observations of gravitational-wave candidates, (iii) provide input data on the matter distribution of the local Universe for astrophysical or cosmological simulations, and (iv) help identifications of host candidates for poorly localized electromagnetic transients, such as gamma-ray bursts observed with the InterPlanetary Network. Both being potential hosts of astrophysical sources of gravitational waves, GLADE includes inactive and active galaxies as well. GLADE was constructed by cross-matching and combining data from five separate (but not independent) astronomical catalogues: GWGC, 2MPZ, 2MASS XSC, HyperLEDA, and SDSS-DR12Q. GLADE is complete up to
dL=37+3−4Mpc in terms of the cumulative B-band luminosity of galaxies within luminosity distance dL, and contains all of the brightest galaxies giving half of the total B-band luminosity up to dL=91Mpc. As B-band luminosity is expected to be a tracer of binary neutron star mergers (currently the prime targets of joint GW+EM detections), our completeness measures can be used as estimations of completeness for containing all binary neutron star merger hosts in the local Universe
Crystallization, data collection and data processing of maltose-binding protein (MalE) from the phytopathogen Xanthomonas axonopodis pv. citri
Maltose-binding protein is the periplasmic component of the ABC transporter
responsible for the uptake of maltose/maltodextrins. The Xanthomonas axonopodis
pv. citri maltose-binding protein MalE has been crystallized at 293 Kusing
the hanging-drop vapour-diffusion method. The crystal belonged to the
primitive hexagonal space group P6_122, with unit-cell parameters a = 123.59,
b = 123.59, c = 304.20 Å, and contained two molecules in the asymetric unit. It
diffracted to 2.24 Å resolution
Efeito do ácido indolbutírico no enraizamento adventício em estacas de cupuaçuzeiro
A estaquia é um dos processos mais importantes de propagação vegetativa, sendo que sua aplicação na multiplicação vegetativa de fruteiras tropicais, tal como o cupuaçuzeiro (Theobroma grandiflorum), constitui uma ferramenta importante na redução de custos da produção de mudas e possibilitar a rápida multiplicação de material elite. Neste sentido, considerando a escassez de informações e a necessidade do desenvolvimento desta técnica para a produção de mudas clonais de T. grandiflorum, o presente trabalho teve como objetivo avaliar o efeito do ácido indolbutírico no enraizamento adventício de estacas de cupuaçuzeiro
de Broglie-Proca and Bopp-Podolsky massive photon gases in cosmology
We investigate the influence of massive photons on the evolution of the
expanding universe. Two particular models for generalized electrodynamics are
considered, namely de Broglie-Proca and Bopp-Podolsky electrodynamics. We
obtain the equation of state (EOS) for each case using
dispersion relations derived from both theories. The EOS are inputted into the
Friedmann equations of a homogeneous and isotropic space-time to determine the
cosmic scale factor . It is shown that the photon non-null mass does not
significantly alter the result valid for a massless photon
gas; this is true either in de Broglie-Proca's case (where the photon mass
is extremely small) or in Bopp-Podolsky theory (for which is extremely
large).Comment: 8 pages, 2 figures; v2 matches the published versio
Nuclear isotope thermometry
We discuss different aspects which could influence temperatures deduced from
experimental isotopic yields in the multifragmentation process. It is shown
that fluctuations due to the finite size of the system and distortions due to
the decay of hot primary fragments conspire to blur the temperature
determination in multifragmentation reactions. These facts suggest that caloric
curves obtained through isotope thermometers, which were taken as evidence for
a first-order phase transition in nuclear matter, should be investigated very
carefully.Comment: 9 pages, 7 figure
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