The Universe in 3D, a brief presentation, will open the exhibition in Tegueste next Saturday, 19 January, at 19:30 in the Prebend Pacheco Hall

Stellar-mass black holes (BHs) are mostly found in X-ray transients, a subclass of X-ray binaries that exhibit violent outbursts. None of the ~50 galactic BHs known show eclipses, which is surprising for a random distribution of inclinations. Swift J1357.2−093313 is a very faint X-ray transient detected in 2011 by the Swift telescope. Our spectroscopic evidences show that it contains a BH in a 2.8h orbital period. High-time resolution optical light curves display profound dips of up to 0.8 mag (50% of the optical flux) in 2min without X-ray counterparts. The observed properties are best

Despite its importance for understanding the nature of early stellar generations and for constraining Galactic bulge formation models, at present little is known about the metal-poor stellar content of the central Milky Way. This is a consequence of the great distances involved and intervening dust obscuration, which challenge optical studies. However, the Apache Point Observatory Galactic Evolution Experiment (APOGEE), a wide-area, multifiber, high-resolution spectroscopic survey within Sloan Digital Sky Survey III (SDSS-III), is exploring the chemistry of all Galactic stellar populations

We present the first application of Bayesian model comparison techniques for solar atmospheric seismology. The detection of multiple mode harmonic kink oscillations in coronal loops enables to obtain information on coronal density stratification and magnetic field expansion using seismology inversion techniques. The inference is based on the measurement of the period ratio between the fundamental mode and the first overtone and theoretical results for the period ratio under the hypotheses of coronal density stratification and magnetic field expansion of the wave guide. We present a Bayesian

Rotation plays a key role in the life cycles of stars with masses above 8 Msun. Hence, accurate knowledge of the rotation rates of such massive stars is critical for understanding their properties and for constraining models of their evolution.This paper investigates the reliability of current methods used to derive projected rotation speeds v sin i from line-broadening signatures in the photospheric spectra of massive stars, focusing on stars that are not rapidly rotating.We use slowly rotating magnetic O-stars with well-determined rotation periods to test the Fourier transform (FT) and

Using the OSIRIS tunable narrow band imager on the 10.4m GTC (La Palma) we have mapped the SAB(rs)cd galaxy NGC 6946 over a 7.3x7.5 square arcminutes field in the emission lines of the [SII]\lambda\lambda, 6717, 6731 doublet, and in H\alpha. From these maps we have produced catalogs of the H\alpha luminosities and effective radii of 557 HII regions across the disk, and derived the [SII] emission line ratios of 370 of these. The H\alpha observations were used to derive the mean luminosity-weighted electron densities for the regions of the sample, while the [SII] line ratios allowed us to