Multi-filter transit observations of WASP-39b and WASP-43b with three San Pedro M\'artir telescopes

Three optical telescopes located at the San Pedro M\'artir National Observatory were used for the first time to obtain multi-filter defocused photometry of the transiting extrasolar planets WASP-39b and WASP-43b. We observed WASP-39b with the 2.12m telescope in the U filter for the first time, and additional observations were carried out in the R and I filters using the 0.84m telescope. WASP-43b was observed in VRI with the same instrument, and in the i filter with the robotic 1.50m telescope. We reduced the data using different pipelines and performed aperture photometry with the help of custom routines, in order to obtain the light curves. The fit of the light curves (1.5--2.5mmag rms), and of the period analysis, allowed a revision of the orbital and physical parameters, revealing for WASP-39b a period ($4.0552947 \pm 9.65 \times 10^{-7}$ days) which is $3.084 \pm 0.774$ seconds larger than previously reported. Moreover, we find for WASP-43b a planet/star radius ($0.1738 \pm 0.0033$) which is $0.01637 \pm 0.00371$ larger in the i filter with respect to previous works, and that should be confirmed with additional observations. Finally, we confirm no evidence of constant period variations in WASP-43b.Comment: 13 pages, 7 figures, accepted in PASP, scheduled for the February 1, 2015 issu

Plan de negocio para una empresa dedicada al acopio y comercializaci?n de botellas de pl?stico PET en Lima Metropolitana

Reciclo tiene como propuesta de negocio incentivar la recolecci?n y comercializaci?n de botellas de pl?stico PET de forma din?mica ofreciendo un beneficio por acopiar botellas. El presente plan de negocio nace de un problema recurrente en el pa?s con el volumen de desechos que encontramos en las diferentes calles, r?os y mares, donde los residuos s?lidos est?n en constante circulaci?n y permanecen a?os antes de degradarse. Nos parece importante resaltar que algunos distritos dentro de Lima metropolitana ya cuentan con un plan de reciclaje con sus vecinos tales son el ejemplo de los distritos de Santiago de Surco y San Borja, donde el proceso de recojo de su basura sea preseleccionado por los mismos habitantes, en ello existe un trabajo compartido donde las municipales ofrecen bolsas de diferentes colores a sus habitantes para la diferenciaci?n del mismo. La cual es una excelente oportunidad para que las personas perciban un beneficio por acopiar las botellas que ya viene compartiendo con las municipalidades. Buscamos una conexi?n directa con nuestros usuarios, poniendo a disposici?n nuestro servicio en los principales supermercados y centros comerciales, con ello no solo daremos una oportunidad diferente de reciclar, sino que tambi?n se podr? obtener descuentos en cines

VizieR Online Data Catalog: WASP-39b and WASP-43b light curves (Ricci+, 2015)

The instrument comes with a set of standard UBVRI Johnson filters among others. We present observations carried out using the VRI filters. Light curves of WASP-39b were obtained with the 0.84m telescope in R and I bands and with the 2.12m telescope in the U band. Light curves of WASP-43b were obtained with the 0.84m telescope in VRI bands and with the 1.50m telescope in the Gunn-i band. (2 data files

The Evolution of Central Group Galaxies in Hydrodynamical Simulations

We trace the evolution of central galaxies in three ~10^13 M_sun galaxy groups simulated at high resolution in cosmological hydrodynamical simulations. The evolution in the group potential leads, at z=0, to central galaxies that are massive, gas-poor early-type systems supported by stellar velocity dispersion resembling either elliptical or S0 galaxies. Their z~2-2.5 main progenitors are massive M* ~ 3-10 x 10^10 M_sun, star forming (20-60 M_sun/yr) galaxies which host substantial reservoirs of cold gas (~5 x 10^9 M_sun) in extended gas disks. Our simulations thus show that star forming galaxies observed at z~2 are likely the main progenitors of central galaxies in galaxy groups at z=0. Their central stellar densities stay approximately constant from z~1.5 down to z=0. Instead, the galaxies grow inside-out, by acquiring a stellar envelope outside the innermost ~2 kpc. Consequently the density within the effective radius decreases by up to two orders of magnitude. Both major and minor mergers contribute to most of the mass accreted outside the effective radius and thus drive the evolution of the half-mass radii. In one of the three simulated groups the short central cooling time leads to a dramatic rejuvenation of the central group galaxy at z<1, affecting its morphology, kinematics and colors. This episode is eventually terminated by a group-group merger. Our simulations demonstrate that, in galaxy groups, the interplay between halo mass assembly, galaxy merging and gas accretion has a substantial influence on the star formation histories and z=0 morphologies of central galaxies.[Abridged]Comment: 28 pages, 23 figures, 9 tables, accepted to APJ (revised to match accepted version

Two-dimensional kinematics of SLACS lenses: III. Mass structure and dynamics of early-type lens galaxies beyond z ~ 0.1

We combine in a self-consistent way the constraints from both gravitational lensing and stellar kinematics to perform a detailed investigation of the internal mass distribution, amount of dark matter, and dynamical structure of the 16 early-type lens galaxies from the SLACS Survey, at z = 0.08 - 0.33, for which both HST/ACS and NICMOS high-resolution imaging and VLT VIMOS IFU spectroscopy are available. Based on this data set, we analyze the inner regions of the galaxies, i.e. typically within one (3D) effective radius r_e, under the assumption of axial symmetry and by constructing dynamical models supported by two-integral stellar DFs. For all systems, the total mass density distribution is found to be well approximated by a simple power-law: this profile is on average slightly super-isothermal, with a logarithmic slope = 2.074^{+0.043}_{-0.041} (68% CL) and an intrinsic scatter 0.144^{+0.055}_{-0.014}, and is fairly round, with an average axial ratio = 0.77+/-0.04. The lower limit for the dark matter fraction (fDM) inside r_e ranges, in individual systems, from nearly zero to almost a half, with a median value of 12%. By including stellar masses derived from SPS models with a Salpeter IMF, we obtain an average fDM = 31%. The fDM rises to 61% if, instead, a Chabrier IMF is assumed. For both IMFs, the dark matter fraction increases with the total mass of the galaxy (3-sigma correlation). Based on the intrinsic angular momentum parameter calculated from our models, we find that the galaxies can be divided into two dynamically distinct groups, which are shown to correspond to the usual classes of the slow and fast rotators. Overall, the SLACS systems are structurally and dynamically very similar to their nearby counterparts, indicating that the inner regions of early-type galaxies have undergone little, if any, evolution since redshift z ~ 0.35. (Abridged)Comment: 27 pages, 34 figures. MNRAS, in pres

Scalar-field Pressure in Induced Gravity with Higgs Potential and Dark Matter

A model of induced gravity with a Higgs potential is investigated in detail in view of the pressure components related to the scalar-field excitations. The physical consequences emerging as an artifact due to the presence of these pressure terms are analysed in terms of the constraints parting from energy density, solar-relativistic effects and galactic dynamics along with the dark matter halos.Comment: 26 pages, 3 figures, Minor revision, Published in JHE

STREGA: STRucture and Evolution of the GAlaxy - I : Survey overview and first results

STREGA (STRucture and Evolution of the GAlaxy) is a guaranteed time survey being performed at the VST (the ESO Very Large Telescope Survey Telescope) to map about 150 square degrees in the Galactic halo, in order to constrain the mechanisms of galactic formation and evolution. The survey is built as a 5 yr project, organized in two parts: a core programme to explore the surrounding regions of selected stellar systems and a second complementary part to map the southern portion of the Fornax orbit and extend the observations of the core programme. The adopted stellar tracers are mainly variable stars (RR Lyraes and long-period variables) and main-sequence turn-off stars for which observations in the g, r, i bands are obtained. We present an overview of the survey and some preliminary results for three observing runs that have been completed. For the region centred on ω Cen (37 deg^2), covering about three tidal radii, we also discuss the detected stellar density radial profile and angular distribution, leading to the identification of extratidal cluster stars. We also conclude that the cluster tidal radius is about 1.2 deg, in agreement with values in the literature based on the Wilson model.Peer reviewedFinal Accepted Versio

Highlights from the Pierre Auger Observatory

The Pierre Auger Observatory is the world's largest cosmic ray observatory. Our current exposure reaches nearly 40,000 km$^2$ str and provides us with an unprecedented quality data set. The performance and stability of the detectors and their enhancements are described. Data analyses have led to a number of major breakthroughs. Among these we discuss the energy spectrum and the searches for large-scale anisotropies. We present analyses of our X$_{max}$ data and show how it can be interpreted in terms of mass composition. We also describe some new analyses that extract mass sensitive parameters from the 100% duty cycle SD data. A coherent interpretation of all these recent results opens new directions. The consequences regarding the cosmic ray composition and the properties of UHECR sources are briefly discussed.Comment: 9 pages, 12 figures, talk given at the 33rd International Cosmic Ray Conference, Rio de Janeiro 201