The formation of planetary disks and winds: an ultraviolet view

Planetary systems are angular momentum reservoirs generated during star formation. This accretion process produces very powerful engines able to drive the optical jets and the molecular outflows. A fraction of the engine energy is released into heating thus the temperature of the engine ranges from the 3000K of the inner disk material to the 10MK in the areas where magnetic reconnection occurs. There are important unsolved problems concerning the nature of the engine, its evolution and the impact of the engine in the chemical evolution of the inner disk. Of special relevance is the understanding of the shear layer between the stellar photosphere and the disk; this layer controls a significant fraction of the magnetic field building up and the subsequent dissipative processes ougth to be studied in the UV. This contribution focus on describing the connections between 1 Myr old suns and the Sun and the requirements for new UV instrumentation to address their evolution during this period. Two types of observations are shown to be needed: monitoring programmes and high resolution imaging down to, at least, milliarsecond scales.Comment: Accepted for publication in Astrophysics and Space Science 9 figure

Science with the World Space Observatory - Ultraviolet

The World Space Observatory-Ultraviolet (WSO-UV) will provide access to the UV range during the next decade. The instrumentation on board will allow to carry out high resolution imaging, high sensitivity imaging, high resolution (R~55000) spectroscopy and low resolution (R~2500) long slit spectroscopy. In this contribution, we briefly outline some of the key science issues that WSO-UV will address during its lifetime. Among them, of special interest are: the study of galaxy formation and the intergalactic medium; the astronomical engines; the Milky Way formation and evol ution, and the formation of the Solar System and the atmospheres of extrasolar p lanets.Comment: Just one text file (aigomezdecastro.tex). To be published in the proceeding of the conference: "New Quest in Stellar Astrophysics II: UV properties of evolved stellar populations" held in Puerto Vallarta - Mexico, in april 200

AK Sco, first detection of a highly disturbed atmosphere in a pre-main sequence close binary

AK Sco is a unique source: a ~10 Myrs old pre-main sequence spectroscopic binary composed of two nearly equal F5 stars that at periastron are separated by barely eleven stellar radii so, the stellar magnetospheres fill the Roche lobe at periastron. The orbit is not yet circularized (e=0.47) and very strong tides are expected. This makes of AK Sco, the ideal laboratory to study the effect of gravitational tides in the stellar magnetic field building up during pre-main sequence (PMS) evolution. In this letter, the detection of a highly disturbed (sigma ~ 100 km/s) and very dense atmosphere (ne = 1.6e10cm-3) is reported. Significant line broadening blurs any signs of ion belts or bow shocks in the spectrum of the atmospheric plasma. The radiative loses cannot be accounted solely by the dissipation of energy from the tidal wave propagating in the stellar atmosphere; neither by the accreting material. The release of internal energy from the star seems to be the most likely source of the plasma heating. This is the first clear indication of a highly disturbed atmosphere surrounding a pre-main sequence close binary.Comment: 10 pages 2 figures. Astrophysical Journal Letters, accepte

Evidence of hot high velocity photoionized plasma falling on actively accreting T Tauri stars

The He II (1640 angstrom) line and the resonance doublet of N V (UV1) provide a good diagnostic tool to constrain the excitation mechanism of hot (T-e > 40,000 K) atmospheric/magnetospheric plasmas in T Tauri stars (TTSs). Making use of the data available in the Hubble Space Telescope archive, this work shows that there are at least two distinct physical components contributing to the radiation in these tracers: the accretion flow sliding on the magnetosphere and the atmosphere. The N V profiles in most sources are symmetric and at rest with respect to the star. The velocity dispersion of the profile increases from non-accreting (sigma = 40 km s (1)) to accreting (sigma = 120 km s (1)) TTSs, suggesting that the macroturbulence field in the line formation region decreases as the stars approach the main sequence. Evidence of the N V line being formed in a hot solar-like wind has been found in RW Aur, HN Tau, and AA Tau. The He II profile has a strong narrow component that dominates the line flux; the dispersion of this component ranges from 20 to 60 km s (1). Current data suggest that both accretion shocks and atmospheric emission might contribute to the line flux. In some sources, the He II line shows a broad and redward-shifted emission component often accompanied by semiforbidden O III] emission that has a critical electron density of similar to 3.4 x 10(10) cm(3). In spite of their different origins (inferred from the kinematics of the line formation region), N V and He II fluxes are strongly correlated, with only the possible exception of some of the heaviest accretors

Subarcsecond images of CW-Tauri - constraints on disk size and jet formation

Subarcsecond spatial resolution images in the [S II] and [N II] + Halpha emission lines of the T Tauri star (TTS) CW Tau are presented. It is shown that CW Tau has a jet that extends up to 2.2'' (300 AU) from the star in the direction P.A. = 144-degrees. The jet emits strongly in [S II], and it is already collimated at 1.3'' (176 AU) from the star. The images also indicate that CW Tau is extended in the east-west direction and that the jet is slightly shifted to the east. This suggests that CW Tau may be a binary with the two components separated 0.20'' (28 AU). The observations are compared with the theoretical models proposed for the production of forbidden line emission regions (FLERs) and protostellar jets

Realismo Pedagógico

Desde una exposición centrada en el concepto de realismo y la clarificación de su significado se llega a entender cómo repercute el conocimiento en la pedagogía. Su importancia junto y en contraste con otros conocimientos deja claro el interés por una etapa crucial de la Humanidad. Todo envuelto en una ajustada ambición de conceptos y de su significación pedagógica

El concepto de Formacion General en Giner.

Sin resume

WUVS Simulator: Detectability of spectral lines with the WSO-UV spectrographs

The World Space Observatory - Ultraviolet (WSO-UV) space telescope is equipped with high dispersion (55,000) spectrographs working in the 1150-3100 {\AA} spectral range. To evaluate the impact of the design on the scientific objectives of the mission, a simulation software tool has been developed. This simulator builds on the development made for the PLATO space mission, and it is designed to generate synthetic time-series of images by including models of all important noise sources. In this article, we describe its design and performance. Moreover, its application to the detectability of important spectral features for star formation and exoplanetary research is addressed.Comment: 8 pages, 5 figure