The IACOB project: A grid-based automatic tool for the quantitative spectroscopic analysis of O-stars

We present the IACOB grid-based automatic tool for the quantitative spectroscopic analysis of O-stars. The tool consists of an extensive grid of FASTWIND models, and a variety of programs implemented in IDL to handle the observations, perform the automatic analysis, and visualize the results. The tool provides a fast and objective way to determine the stellar parameters and the associated uncertainties of large samples of O-type stars within a reasonable computational time.Comment: 8 pages, 2 figures, 1 table. Proceedings of the "GREAT-ESF Stellar Atmospheres in the Gaia Era Workshop

Globalization of twisted partial actions

Let A be a unital ring which is a product of possibly infinitely many indecomposable rings. We establish criteria for the existence of a globalization for a given twisted partial action of a group on A. If the globalization exists, it is unique up to a certain equivalence relation and, moreover, the crossed product corresponding to the twisted partial action is Morita equivalent to that corresponding to its globalization. For arbitrary unital rings the globalization problem is reduced to an extendibility property of the multipliers involved in the twisted partial action.Comment: 27 pages. To appear in Trans. Amer. Math. Soc

OB stars at the lowest Local Group metallicity: GTC-OSIRIS observations of Sextans A

Our aim is to find and classify OB stars in Sextans A, to later determine accurate stellar parameters of these blue massive stars in this low metallicity region $(Z \sim 0.1 \rm Z_{\odot})$. Using UBV photometry, the reddening-free index Q and GALEX imaging, we built a list of blue massive star candidates in Sextans A. We obtained low resolution (R $\sim$ 1000) GTC-OSIRIS spectra for a fraction of them and carried out spectral classification. For the confirmed O-stars we derive preliminary stellar parameters. The target selection criteria and observations were successful and have produced the first spectroscopic atlas of OB-type stars in Sextans A. From the whole sample of 18 observed stars, 12 were classified as early OB-types, including 5 O-stars. The radial velocities of all target stars are in agreement with their Sextans A membership, although three of them show significant deviations. We determined the stellar parameters of the O-type stars using the stellar atmosphere code FASTWIND, and revisited the sub-SMC temperature scale. Two of the O-stars are consistent with relatively strong winds and enhanced helium abundances, although results are not conclusive. We discuss the position of the OB stars in the HRD. Initial stellar masses run from slightly below 20 up to 40 solar masses. The target selection method worked well for Sextans A, confirming the procedure developed in Garcia \& Herrero (2013). The stellar temperatures are consistent with findings in other galaxies. Some of the targets deserve follow-up spectroscopy because of indications of a runaway nature, an enhanced helium abundance or a relatively strong wind. We observe a correlation between HI and OB associations similar to the irregular galaxy IC1613, confirming the previous result that the most recent star formation of Sextans A is currently on-going near the rim of the H\,{\sc I} cavity

Joaquim Hugas i Wenceslao Marín, oftalmòlegs catalans (i la ginecòloga Montserrat Bobé)

Dades biogràfiques sobre Joaquim Hugas, el primer veritable metge oculista de Girona i pare de la primera dona òptica de la ciutat. També es dóna notícia de l’oftalmòleg Wenceslao Marín, que es va casar amb la manresana Montserrat Bobé, una de les poques dones que van estudiar Medicina a Barcelona a cavall de finals del segle XIX i principis del XX.Se aportan datos biográficos sobre que fue el primer médico oculista que ejerció en Gerona, y padre de la primera mujer óptica en la ciudad. También se da noticia del oftalmólogo Wenceslao Marín, que ejerció en Barcelona,  casado con Montserrat Bobé, de Manresa, una de las primeras mujeres que se licenció en Barcelona, cursando estudios en los años de cambio de siglo XIX al XX

Sobre el Dr. Lluís Noguer i Molins (1886-1972)

Dades biogràfiques sobre el Dr. Lluís Noguer Molins (1886-1972). Relaciódetallada dels seus llibres i de la seva trajectòria universitària a Espanya. Notícia sobre la seva activitat docent a l’Universitat “Los Andes” de Mérida, VeneçuelaDatos biográficos sobre el Dr. Luis Noguer Molins (1886-1972). Relación detallada de sus libros y de su trayectoria detallada en España. Noticia sobre su actividad docente en la Universidad “Los Andes” de Mérida (Venezuela)

The chemical composition of the Orion star forming region: stars, gas and dust

We present a summary of main results from the studies performed in the series of papers "The chemical composition of the Orion star forming region". We reinvestigate the chemical composition of B-type stars in the Orion OB1 association by means of state-of-the-art stellar atmosphere codes, atomic models and techniques, and compare the resulting abundances with those obtained from the emission line spectra of the Orion nebula (M42), and recent determinations of the Solar chemical composition.Comment: 5 pages, 4 figures, 2 tables. Poster contribution to the proceedings of the LIAC2010 conference "The multi-wavelength view of hot, massive stars