News

This section includes scientific and technological news from the IAC and its Observatories, as well as press releases on scientific and technological results, astronomical events, educational projects, outreach activities and institutional events.

  • VIMOS-IFU spectroscopy of the shock front in the remnant of SN 1006. The top-left panel shows a composite imageof the full remnant (≈30′ in diameter), combining data from the Very Large Array and Green Bank Telescope (red;NRAO/AUI/NSF/GBT/VLA/Dyer, Maddal
    Supernova remnants are among the most spectacular examples of astrophysical pistons in our cosmic neighborhood. The gas expelled by the supernova explosion is launched with velocities ∼1000 km/s into the ambient, tenuous interstellar medium, producing shocks that excite hydrogen lines. We have used an optical integral-field spectrograph to obtain high-resolution spatial-spectral maps that allow us to study in detail the shocks in the northwestern rim of supernova 1006. The two-component Halpha line is detected at 133 sky locations. Variations in the broad line widths and the broad-to-narrow
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  • 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
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  • Artist's impression of complex fullerenes (carbon onions or multishell fullerenes such as C60@C240 and C60@C240@C540) produced by a planetary nebula and expelled into the interstellar medium. The connection between these molecules and certain diffuse inte
    We have found evidence that the presence of ‘carbon onions’ and other large molecules derived from fullerene could be commonplace in space. These are the most complex molecules detected so far and their discovery has important implications regarding our understanding of circumstellar and interstellar physics and chemisty, as well as of molecular processes in the final stages of stellar evolution. The work also provides new insights into understanding the origin and composition of the so-called diffuse interstellar bands (DIBs), one of the most enigmatic phenomena in astrophysics. Discovered
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  • Selection window employed to look for our LBGs at z ~ 3 (light grey shaded zone). Black dots are the complete sample of galaxies in the Capak et al. (2004) photometric catalog. Red filled dots represent the sample of LBGs spectroscopically confirmed to be
    Lyman break galaxies (LBGs) represent one of the kinds of star-forming galaxies that are found in the high-redshift universe. The detection of LBGs in the FIR domain can provide very important clues on their dust attenuation and total star-formation rate (SFR), allowing a more detailed study than those performed so far. In this work we explore the FIR emission of a sample of 16 LBGs at z ~ 3 in the GOODS-North and GOODS-South fields that are individually detected in PACS-100um or PACS-160um. These detections demonstrate the possibility of measuring the dust emission of LBGs at high redshift
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  • Redshift evolution of the ratio of the relic galaxies to the total number of massive galaxies. The three different lines represent the three considered models. Coloured areas, orange (orange-red) show galaxies that have increased their masses less than a
    The number of present-day massive galaxies that has survived untouched since their formation at high-z is an important observational constraint to the hierarchical galaxy formation models. Using three different semianalytical models based on the Millenium simulation, we quantify the expected fraction and number densities of the massive galaxies form at z>2 which have evolved in stellar mass less than 10% and 30%. We find that only a small fraction of the massive galaxies already form at z~2 have remained almost unaltered since their formation (<2% with Delta_M*/M*<0.1 and <8% with Delta_M*/M
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  • Abundance ratios of oxygen, magnesium and silicon relative to iron for the five stars in the bulge discovered by APOGEE (black filled circles) and literature values for other populations in the bulge (open circles), halo (squares), thin disk (crosses) and
    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
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