Proyecto IACOB: Una Nueva Era en el Estudio de Estrellas OB Galácticas

Año de inicio
2014
Año fin
2017
Unidad organizativa

Subvenciones relacionadas:

    General
    Descripción

    Massive stars has been many times claimed as Cosmic Engines and Gifts of Nature for the study of the Universe, from the Solar neighbourhood to the large-z Universe. The complete understanding of the physical properties and evolution of massive stars (and their interplay with the ISM) is crucial for many fields of Astrophysics and, ultimately, to understand the evolution of the Cosmos. In spite of the remarkable avances in the modelling and spectroscopic analysis techniques of these stars occurred in the last two decades, our knowledge of these important (but complex) astrophysical objects has been, until very recently, limited to conclusions extracted from the analysis of single-epoch medium resolution spectroscopic observations of relatively small samples. This situation is slowly but surely changing with the compilation and analysis of large spectroscopic surveys of OB stars in the Milky Way and other external galaxies. The IACOB project is an ambitious long-term project which is contributing to the new era of investigation of massive stars by concentrating on Galactic OB stars. In particular, the project aims at building a large database of high-resolution, multi-epoch, spectra of Galactic OB stars (uisng the FIES@NOT2.5m and HERMES@MERCATOR1.2m facilities at the ORM observatory, La Palma, Spain), and the scientific exploitation of the database using state-of-the-art models and techniques. The main drivers of the project are: (1) to increase the statistics of Galactic OB stars with accurate physical parameters and abundances, (2) to investigate in detail some of the still open questions in our knowledge of the physical properties and evolution of massive stars (e.g., the actual masses of these stars, the nature of the O Vz stars, the driving mechanism of stellar winds in the weak wind regime, the uncertain stage of B supergiants in an evolutionary context, the actual rotational velocities of massive stars, the physical origin of the macroturbulent broadening, and the impact of rotation/binarity/pulsations on the evolution of massive stars), and (3) to provide an unique ground-based spectroscopic database supporting/complementing the future Gaia database.

    Investigador principal
    Colaboradores
    Dr.
    KLAUS SIMON RUBKE ZUÑIGA
    Dr.
    INÉS CAMACHO IÑESTA
    Dr.
    Jesús Maíz Apellaniz
    Dr.
    Ignacio Negueruela
    Dr.
    Norberto Castro
    Dr.
    Carolina Sabín-Sanjulian
    Dr.
    Javier Lorenzo
    Dr.
    Ricardo Dorda e
    Dr.
    María Fernanda Nieva
    Dr.
    Jorge García-Rojas
    Dr.
    Nevy Markova
    Dr.
    Miguel A. Urbaneja
    Dr.
    Rodolfo Barbá
    Dr.
    Julia Arias

    Publicaciones relacionadas

    • MEGARA: a new generation optical spectrograph for GTC
      MEGARA (Multi-Espectrógrafo en GTC de Alta Resolución para Astronomía) is an optical Integral-Field Unit (IFU) and Multi-Object Spectrograph (MOS) designed for the GTC 10.4m telescope in La Palma. MEGARA offers two IFU fiber bundles, one covering 12.5x11.3 arcsec2 with a spaxel size of 0.62 arcsec (Large Compact Bundle; LCB) and another one
      Gil de Paz, A. et al.

      Fecha de publicación:

      7
      2014
      Número de citas
      8
    • The B Fields in OB Stars (BOB) Survey
      The B fields in OB stars (BOB) survey is an ESO Large Programme collecting spectropolarimetric observations for a large number of early-type stars in order to study the occurrence rate, properties, and ultimately the origin of magnetic fields in massive stars. A total of 98 objects was observed over 20 nights with FORS2 and HARPSpol to July 2014
      Morel, T. et al.

      Fecha de publicación:

      9
      2014
      Número de citas
      36
    • The Cocoon nebula and its ionizing star: do stellar and nebular abundances agree?
      Context. Main-sequence massive stars embedded in an H ii region should have the same chemical abundances as the surrounding nebular gas+dust. The Cocoon nebula (IC 5146), a close-by Galactic H ii region ionized by a narrow line B0.5 V single star (BD+46 3474), is an ideal target to compare nebular and stellar abundances in detail in the same
      García-Rojas, J. et al.

      Fecha de publicación:

      11
      2014
      Número de citas
      25
    • The spectroscopic Hertzsprung-Russell diagram of Galactic massive stars
      The distribution of stars in the Hertzsprung-Russell diagram narrates their evolutionary history and directly assesses their properties. Placing stars in this diagram however requires the knowledge of their distances and interstellar extinctions, which are often poorly known for Galactic stars. The spectroscopic Hertzsprung-Russell diagram (sHRD)
      Castro, N. et al.

      Fecha de publicación:

      10
      2014
      Número de citas
      108
    • The IACOB project. II. On the scatter of O-dwarf spectral type - effective temperature calibrations
      Context. We are now in an era of large spectroscopic surveys of OB-type stars. Quantitative spectroscopic analysis of these modern datasets is enabling us to review the physical properties of blue massive stars with robust samples, not only revisiting mean properties and general trends, but also incorporating information about the effects of second
      Simón-Díaz, S. et al.

      Fecha de publicación:

      10
      2014
      Número de citas
      27
    • On the use of the Fourier transform to determine the projected rotational velocity of line-profile variable B stars
      Context. The Fourier transform method is a popular tool for deriving the rotational velocities of stars from their spectral line profiles. However, its domain of validity does not include line-profile variables with time-dependent profiles. Aims: We investigate the performance of the method for such cases, by interpreting the line-profile
      Aerts, C. et al.

      Fecha de publicación:

      9
      2014
      Número de citas
      47
    • Masgomas-4: Physical characterization of a double-core obscured cluster with a massive and very young stellar population
      Context. The discovery of new, obscured massive star clusters has changed our understanding of the Milky Way star-forming activity from a passive to a very active star-forming machine. The search for these obscured clusters is strongly supported by the use of all-sky, near-IR surveys. Aims: The main goal of the MASGOMAS project is to search for and
      Ramírez Alegría, S. et al.

      Fecha de publicación:

      7
      2014
      Número de citas
      6
    • Astrophysical parameters and orbital solution of the peculiar X-ray transient IGR J00370+6122
      Context. BD + 60° 73 is the optical counterpart of the X-ray source IGR J00370+6122, a probable accretion-powered X-ray pulsar. The X-ray light curve of this binary system shows clear periodicity at 15.7 d, which has been interpreted as repeated outbursts around the periastron of an eccentric orbit. Aims: We aim to characterise the binary system
      Karpen, J. T. et al.

      Fecha de publicación:

      6
      2014
      Número de citas
      14
    • Sher 25: pulsating but apparently alone
      The blue supergiant Sher 25 is surrounded by an asymmetric, hourglass-shaped circumstellar nebula, which shows similarities to the triple-ring structure seen around SN 1987A. From optical spectroscopy over six consecutive nights, we detect periodic radial velocity variations in the stellar spectrum of Sher 25 with a peak-to-peak amplitude of ˜12 km
      Taylor, W. D. et al.

      Fecha de publicación:

      8
      2014
      Número de citas
      14
    • The IACOB project. I. Rotational velocities in northern Galactic O- and early B-type stars revisited. The impact of other sources of line-broadening
      Context. Stellar rotation is an important parameter in the evolution of massive stars. Accurate and reliable measurements of projected rotational velocities in large samples of OB stars are crucial to confront the predictions of stellar evolutionary models with observational constraints. Aims: We reassess previous determinations of projected
      Simón-Díaz, S. et al.

      Fecha de publicación:

      2
      2014
      Número de citas
      242
    • A Be-type star with a black-hole companion
      Stellar-mass black holes have all been discovered through X-ray emission, which arises from the accretion of gas from their binary companions (this gas is either stripped from low-mass stars or supplied as winds from massive ones). Binary evolution models also predict the existence of black holes accreting from the equatorial envelope of rapidly
      Simón-Díaz, S. et al.

      Fecha de publicación:

      1
      2014
      Número de citas
      165
    • Astrophysical parameters of the peculiar X-ray transient IGR J11215-5952
      Context. The current generation of X-ray satellites has discovered many new X-ray sources that are difficult to classify within the well-described subclasses. The hard X-ray source IGR J11215-5952 is a peculiar transient, displaying very short X-ray outbursts every 165 days. Aims: To characterise the source, we obtained high-resolution spectra of
      Herrero, A. et al.

      Fecha de publicación:

      2
      2014
      Número de citas
      24
    • Spectroscopic and physical parameters of Galactic O-type stars. II. Observational constraints on projected rotational and extra broadening velocities as a function of fundamental parameters and stellar evolution
      Context. Rotation is of key importance for the evolution of massive star, including their fate as supernovae or gamma-ray bursts. However, the rotational velocities of OB stars are difficult to determine. Aims: Based on our own data for 31 Galactic O stars and incorporating similar data for 86 OB supergiants from the literature, we aim at
      Langer, N. et al.

      Fecha de publicación:

      2
      2014
      Número de citas
      35
    • A High Angular Resolution Survey of Massive Stars in Cygnus OB2: Results from the Hubble Space Telescope Fine Guidance Sensors
      We present results of a high angular resolution survey of massive OB stars in the Cygnus OB2 association that we conducted with the fine guidance sensor 1R (FGS1r) on the Hubble Space Telescope. FGS1r is able to resolve binary systems with a magnitude difference ΔV 4 down to separations as small as 0.''01. The sample includes 58 of the brighter
      Jao, W.-C. et al.

      Fecha de publicación:

      2
      2014
      Número de citas
      36

    Charlas relacionadas

    No se han encontrado charlas relacionadas.

    Congresos relacionados

    No se han encontrado congresos relacionados.