Localization of short duration gravitational-wave transients with the early advanced LIGO and Virgo detectors

The Laser Interferometer Gravitational wave Observatory (LIGO) and Virgo, advanced ground-based gravitational-wave detectors, will begin collecting science data in 2015. With first detections expected to follow, it is important to quantify how well generic gravitational-wave transients can be localized on the sky. This is crucial for correctly identifying electromagnetic counterparts as well as understanding gravitational-wave physics and source populations. We present a study of sky localization capabilities for two search and parameter estimation algorithms: \emph{coherent WaveBurst}, a constrained likelihood algorithm operating in close to real-time, and \emph{LALInferenceBurst}, a Markov chain Monte Carlo parameter estimation algorithm developed to recover generic transient signals with latency of a few hours. Furthermore, we focus on the first few years of the advanced detector era, when we expect to only have two (2015) and later three (2016) operational detectors, all below design sensitivity. These detector configurations can produce significantly different sky localizations, which we quantify in detail. We observe a clear improvement in localization of the average detected signal when progressing from two-detector to three-detector networks, as expected. Although localization depends on the waveform morphology, approximately 50% of detected signals would be imaged after observing 100-200 deg$^2$ in 2015 and 60-110 deg$^2$ in 2016, although knowledge of the waveform can reduce this to as little as 22 deg$^2$. This is the first comprehensive study on sky localization capabilities for generic transients of the early network of advanced LIGO and Virgo detectors, including the early LIGO-only two-detector configuration.Comment: 18 pages, 8 figure

A Talenti-type comparison theorem for RCD(K,N)\mathrm{RCD}(K,N) spaces and applications

We prove pointwise and $L^{p}$-gradient comparison results for solutions to elliptic Dirichlet problems defined on open subsets of a (possibly non-smooth) space with positive Ricci curvature (more precisely of an $\mathrm{RCD}(K,N)$ metric measure space, with $K>0$ and $N\in (1,\infty)$). The obtained Talenti-type comparison is sharp, rigid and stable with respect to $L^{2}$/measured-Gromov-Hausdorff topology; moreover, several aspects seem new even for smooth Riemannian manifolds. As applications of such Talenti-type comparison, we prove a series of improved Sobolev-type inequalities, and an $\mathrm{RCD}$ version of the St.~Venant-P\'olya torsional rigidity comparison theorem (with associated rigidity and stability statements). Finally, we give a probabilistic interpretation (in the setting of smooth Riemannian manifolds) of the aforementioned comparison results, in terms of exit time from an open subset for the Brownian motion.Comment: 35 pages. Final version to appear in Calculus of Variations and Partial Differential Equation

Health Conditions And Factors Related To The Work Ability Of Teachers.

This is a cross-sectional study conducted with 258 teachers from nine state schools in two municipalities of São Paulo state with the purpose of assessing their work ability. A questionnaire with socio-demographic and health/work conditions data and the Work Ability Index (WAI) was performed. Most teachers were females, 41.9 yr old on average (SD 9.4), and with an undergraduate degree (95.7%). The work ability was considered good for 42.6% and moderate/low for 35.3%. In linear regressions models, which used the two domain model, the significant variables for a decrease in WAI were: individual perception of a worsening in the health situation (p<0001), having children (p=0.0003 / p=0.0001), difficulty in sleeping well at night (p=0.0009 / p=0.0014), history of physical pain in the previous six months (p<0.0001 / p<0.0001), being a teacher with a contract (p=0.0007) and working as a teacher for a longer time. (p=0.0183). Public investments on the work conditions of teachers are important to recover and to maintain their work ability.52121-

A dispersive wave pattern on Jupiter's fastest retrograde jet at 20∘20^\circS

A compact wave pattern has been identified on Jupiter's fastest retrograding jet at 20S (the SEBs) on the southern edge of the South Equatorial Belt. The wave has been identified in both reflected sunlight from amateur observations between 2010 and 2015, thermal infrared imaging from the Very Large Telescope and near infrared imaging from the Infrared Telescope Facility. The wave pattern is present when the SEB is relatively quiescent and lacking large-scale disturbances, and is particularly notable when the belt has undergone a fade (whitening). It is generally not present when the SEB exhibits its usual large-scale convective activity ('rifts'). Tracking of the wave pattern and associated white ovals on its southern edge over several epochs have permitted a measure of the dispersion relationship, showing a strong correlation between the phase speed (-43.2 to -21.2 m/s) and the longitudinal wavelength, which varied from 4.4-10.0 deg. longitude over the course of the observations. Infrared imaging sensing low pressures in the upper troposphere suggest that the wave is confined to near the cloud tops. The wave is moving westward at a phase speed slower (i.e., less negative) than the peak retrograde wind speed (-62 m/s), and is therefore moving east with respect to the SEBs jet peak. Unlike the retrograde NEBn jet near 17N, which is a location of strong vertical wind shear that sometimes hosts Rossby wave activity, the SEBs jet remains retrograde throughout the upper troposphere, suggesting the SEBs pattern cannot be interpreted as a classical Rossby wave. Cassini-derived windspeeds and temperatures reveal that the vorticity gradient is dominated by the baroclinic term and becomes negative (changes sign) in a region near the cloud-top level (400-700 mbar) associated with the SEBs, suggesting a baroclinic origin for this meandering wave pattern. [Abr]Comment: 19 pages, 11 figures, article accepted for publication in Icaru

Interference at the Single Photon Level Along Satellite-Ground Channels

Quantum interference arising from superposition of states is a striking evidence of the validity of Quantum Mechanics, confirmed in many experiments and also exploited in applications. However, as for any scientific theory, Quantum Mechanics is valid within the limits in which it has been experimentally verified. In order to extend such limits, it is necessary to observe quantum interference in unexplored conditions such as moving terminals at large distance in Space. Here we experimentally demonstrate single photon interference at a ground station due to the coherent superposition of two temporal modes reflected by a rapidly moving satellite thousand kilometers away. The relative speed of the satellite induces a varying modulation in the interference pattern. The measurement of the satellite distance in real time by laser ranging allowed us to precisely predict the instantaneous value of the interference phase. We then observed the interference patterns with visibility up to $67\%$ with three different satellites and with path length up to 5000 km. Our results attest the viability of photon temporal modes for fundamental tests of Physics and Quantum Communications in Space.Comment: Version accepted for publication in Phys. Rev. Let

RE-THINKING CRISIS AND CRITIQUE IN THE DISCOURSE ON “REFUGEE CRISIS” IN POSTCOLONIAL EUROPE

ABSTRACT Objective: this essay aims at re-thinking crisis and critique in the discourse on “refugee crisis” viewed through the context of migration and European borders, by investigating the role of critique and critical thought in this debate. Methodology: the methodology is based on a postcolonial approach of Europe, in which “post” does not simply deal with a temporary issue. Rather it refers to the way colonialism has shaped the European territory itself, leading to asymmetrical relationships between this continent and ex-colonies that still exist. The methodology used is hypothetical-deductive, by reviewing the literature contained in books, scientific articles and international treaties. Results: the paper, as results, show that is fundamental to re-think the discourse on "refugee crises". Contribution: re-think the discourse on “refugee crisis” viewed through the context of migration and European borders. Keywords: Refugees; Migration; Refugee Crisis RESUMO Objetivo: este artigo visa repensar a crise e a crítica no discurso sobre “crise de refugiados”, visto no contexto da migração e das fronteiras europeias, investigando o papel da crítica e do pensamento crítico neste debate. Metodologia: a metodologia é baseada em uma abordagem pós-colonial da Europa, na qual o “pós” não trata simplesmente de um problema temporário. Pelo contrário, refere-se à forma como o colonialismo moldou o próprio território europeu, levando a relações assimétricas entre este continente e ex-colônias que ainda existem. A metodologia utilizada é hipotético-dedutiva, mediante a revisão de literatura contida em obras, artigos científicos e em tratados internacionais. Resultados: o trabalho mostra que é fundamental repensar o discurso sobre "crise de refugiados". Contribuição: repensar o discurso sobre “crise de refugiados” visto através do contexto da migração e das fronteiras européias. Palavras-chave: refugiados; migração; crise de refugiado