Acciones de respuesta ante el Covid-19 en Brasil y Colombia: ¿Ayuda para quién?

This article analyses the economic measures that have been implemented as a response to the COVID-19 crisis. Latin America and the Caribbean have been hit particularly hard, with an expected contraction of 9.3 percent this year—its largest recession on record. The policy response in the region has been different in every country, however, the monetary and fiscal measures are a priority. In this scenario, this document explores the measures implemented by Colombia and Brazil, in order to identify Which actors/sector have been the most benefited?Este trabajo de investigación se centra en el análisis de las medidas económicas implementadas ante la actual crisis ocasionada por la pandemia por la enfermedad de la COVID-19. Concretamente en los casos de Colombia y Brasil quienes han sido los países latinoamericanos que más medidas económicas implementaron en el primer semestre del 2020.  En este artículo se explorarán las diferencias, semejanzas y los resultados que han tenido estas medidas, con el objetivo de analizar y discutir la orientación de las medidas económicas y de identificar ¿Qué actores/sectores se han visto beneficiados en mayor medida con la implementación de las acciones económicas?. Si bien la posición de los gobiernos de Brasil y Colombia difiere frente a la forma de afrontar la pandemia por la enfermedad de la Covid-19, en ambos casos se ha identificado que las ayudas o han estado dirigidas a los grandes gremios o sistemáticamente están dirigidas al beneficio de un grupo minoritario, priorizando el empresariado tradicional y evidenciando que aún en esta coyuntura, las prácticas de corrupción y el aumento de la desigualdad siguen manifestándose

Search for antiproton decay at the Fermilab Antiproton Accumulator

A search for antiproton decay has been made at the Fermilab Antiproton Accumulator. Limits are placed on thirteen antiproton decay modes. The results include the first explicit experimental limits on the muonic decay modes of the antiproton, and the first limits on the decay modes e- gamma gamma, and e- omega. The most stringent limit is for the decay mode pbar-> e- gamma. At 90% C.L. we find that tau/B(pbar-> e- gamma) > 7 x 10^5 yr. The most stringent limit for decay modes with a muon in the final state is for the decay pbar-> mu- gamma. At 90% C.L. we find that tau/B(pbar-> mu- gamma) > 5 x 10^4 yr.Comment: 20 pages, 8 figures. Submitted to Phys. Rev. D. Final results on 13 channels (was 15) are presente

BEAMS: separating the wheat from the chaff in supernova analysis

We introduce Bayesian Estimation Applied to Multiple Species (BEAMS), an algorithm designed to deal with parameter estimation when using contaminated data. We present the algorithm and demonstrate how it works with the help of a Gaussian simulation. We then apply it to supernova data from the Sloan Digital Sky Survey (SDSS), showing how the resulting confidence contours of the cosmological parameters shrink significantly.Comment: 23 pages, 9 figures. Chapter 4 in "Astrostatistical Challenges for the New Astronomy" (Joseph M. Hilbe, ed., Springer, New York, forthcoming in 2012), the inaugural volume for the Springer Series in Astrostatistic

Search for muonic decays of the antiproton at the Fermilab Antiproton Accumulator

A search for antiproton decay has been made at the Fermilab Antiproton Accumulator. Limits are placed on six antiproton decay modes which contain a final-state muon. At the 90% C.L. we find that tau/B(mu gamma) > 5.0 x 10^4 yr, tau/B(mu pi0) > 4.8 x 10^4 yr, tau/B(mu eta) > 7.9 x 10^3 yr, tau/B(mu gamma gamma) > 2.3 x 10^4 yr, tau/B(mu K0S > 4.3 x 10^3 yr, and tau/B(mu K0L) > 6.5 x 10^3 yr.Comment: 8 pages + 3 Postscript figure

Supernova Simulations and Strategies For the Dark Energy Survey

We present an analysis of supernova light curves simulated for the upcoming Dark Energy Survey (DES) supernova search. The simulations employ a code suite that generates and fits realistic light curves in order to obtain distance modulus/redshift pairs that are passed to a cosmology fitter. We investigated several different survey strategies including field selection, supernova selection biases, and photometric redshift measurements. Using the results of this study, we chose a 30 square degree search area in the griz filter set. We forecast 1) that this survey will provide a homogeneous sample of up to 4000 Type Ia supernovae in the redshift range 0.05<z<1.2, and 2) that the increased red efficiency of the DES camera will significantly improve high-redshift color measurements. The redshift of each supernova with an identified host galaxy will be obtained from spectroscopic observations of the host. A supernova spectrum will be obtained for a subset of the sample, which will be utilized for control studies. In addition, we have investigated the use of combined photometric redshifts taking into account data from both the host and supernova. We have investigated and estimated the likely contamination from core-collapse supernovae based on photometric identification, and have found that a Type Ia supernova sample purity of up to 98% is obtainable given specific assumptions. Furthermore, we present systematic uncertainties due to sample purity, photometric calibration, dust extinction priors, filter-centroid shifts, and inter-calibration. We conclude by estimating the uncertainty on the cosmological parameters that will be measured from the DES supernova data.Comment: 46 pages, 30 figures, resubmitted to ApJ as Revision 2 (final author revision), which has subtle editorial differences compared to the published paper (ApJ, 753, 152). Note that this posting includes PDF only due to a bug in either the latex macros or the arXiv submission system. The source files are available in the DES document database: http://des-docdb.fnal.gov/cgi-bin/ShowDocument?docid=624

A search for antiproton decay at the Fermilab Antiproton Accumulator

We report on the search for anti-proton decay at the Fermilab Antiproton Accumulator Ring. Experiment 868 (APEX) was designed to search for two-body p̄ decay modes containing an electron in the final state (→e+X)(p̄→e+X) and to conduct an exploratory search for decays with a muon in the final state (→μ+X).(p̄→μ+X). Data were taken for three months in the Spring of 1995. Preliminary results yield lower limits on /BRτp̄/BR in the range of 105–106105–106 years for selected channels having an electron in the final state, improving on previous results by approximately 3 orders of magnitude. Additionally, we report the first preliminary results for the →μγp̄→μγ and →μπ0p̄→μπ0 decay channels. © 1997 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87906/2/419_1.pd

Properties of Type Ia supernovae inside rich galaxy clusters

We used the Gaussian Mixture Brightest Cluster Galaxy catalogue and Sloan Digital Sky Survey-II supernovae data with redshifts measured by the Baryon Oscillation Spectroscopic Survey to identify 48 Type Ia supernovae (SNe Ia) residing in rich galaxy clusters and compare their properties with 1015 SNe Ia in the field. Their light curves were parametrized by the SALT2 model and the significance of the observed differences was assessed by a resampling technique. To test our samples and methods, we first looked for known differences between SNe Ia residing in active and passive galaxies. We confirm that passive galaxies host SNe Ia with smaller stretch, weaker colour–luminosity relation [β of 2.54(22) against 3.35(14)], and that are ∼0.1 mag more luminous after stretch and colour corrections. We show that only 0.02 per cent of random samples drawn from our set of SNe Ia in active galaxies can reach these values. Reported differences in the Hubble residuals scatter could not be detected, possibly due to the exclusion of outliers. We then show that, while most field and cluster SNe Ia properties are compatible at the current level, their stretch distributions are different (∼3σ): besides having a higher concentration of passive galaxies than the field, the cluster’s passive galaxies host SNe Ia with an average stretch even smaller than those in field passive galaxies (at 95 per cent confidence).We argue that the older age of passive galaxies in clusters is responsible for this effect since, as we show, old passive galaxies host SNe Ia with smaller stretch than young passive galaxies (∼4σ).Web of Scienc