References of "Rodriguez-Lopez, C"
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See detailFirst Kepler results on compact pulsators - I. Survey target selection and the first pulsators
Ostensen, R. H.; Silvotti, R.; Charpinet, S. et al

in Monthly Notices of the Royal Astronomical Society (2010), 409

We present results from the first two quarters of a survey to search for pulsations in compact stellar objects with the Kepler spacecraft. The survey sample and the various methods applied in its ... [more ▼]

We present results from the first two quarters of a survey to search for pulsations in compact stellar objects with the Kepler spacecraft. The survey sample and the various methods applied in its compilation are described, and spectroscopic observations are presented to separate the objects into accurate classes. From the Kepler photometry we clearly identify nine compact pulsators and a number of interesting binary stars. Of the pulsators, one shows the strong, rapid pulsations typical of a V361 Hya-type sdB variable (sdBV); seven show long-period pulsation characteristics of V1093 Her-type sdBVs; and one shows low-amplitude pulsations with both short and long periods. We derive effective temperatures and surface gravities for all the subdwarf B stars in the sample and demonstrate that below the boundary region where hybrid sdB pulsators are found, all our targets are pulsating. For the stars hotter than this boundary temperature a low fraction of strong pulsators (<10 per cent) is confirmed. Interestingly, the short-period pulsator also shows a low-amplitude mode in the long-period region, and several of the V1093 Her pulsators show low-amplitude modes in the short-period region, indicating that hybrid behaviour may be common in these stars, also outside the boundary temperature region where hybrid pulsators have hitherto been found. [less ▲]

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See detailGround-based observations of the beta Cephei CoRoT main target HD 180642
Briquet, Maryline ULg; Uytterhoeven, K.; Aerts, C. et al

in Communications in Asteroseismology (2009), 158

We present the preliminary results of a detailed study of ground-based photometric and spectroscopic observations dedicated to the β Cephei CoRoT main target HD~180642. Besides the non-linear dominant ... [more ▼]

We present the preliminary results of a detailed study of ground-based photometric and spectroscopic observations dedicated to the β Cephei CoRoT main target HD~180642. Besides the non-linear dominant radial mode several low-amplitude modes are detected in both kinds of datasets. Our aim is to derive the wavenumbers (â ,m) of these modes, as additional constraints to the CoRoT pulsation frequencies, for forthcoming asteroseismic modelling of the star. [less ▲]

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See detailGround-based observations of the beta Cephei CoRoT main target HD 180642
Briquet, Maryline ULg; Uytterhoeven, K.; Aerts, C. et al

Conference (2008, July)

We present the preliminary results of a detailed study of ground-based photometric and spectroscopic observations dedicated to the β Cephei CoRoT main target HD 180642. Besides the non-linear dominant ... [more ▼]

We present the preliminary results of a detailed study of ground-based photometric and spectroscopic observations dedicated to the β Cephei CoRoT main target HD 180642. Besides the non-linear dominant radial mode several low-amplitude modes are detected in both kinds of datasets. Our aim is to derive the wavenumbers (ℓ,m) of these modes, as additional constraints to the CoRoT pulsation frequencies, for forthcoming asteroseismic modelling of the star. [less ▲]

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See detailA procedure for modelling asymptotic g-mode pulsators: The case of gamma Doradus stars
Moya, A.; Suárez, J. C.; Martín-Ruiz, S. et al

in Astronomische Nachrichten (2008), 329

Mode identification is one of the first and main problems we encounter in trying to develop the complete potential of asteroseismology. In the particular case of {g}-mode pulsators, this is still an ... [more ▼]

Mode identification is one of the first and main problems we encounter in trying to develop the complete potential of asteroseismology. In the particular case of {g}-mode pulsators, this is still an unsolved problem, from both the observational and theoretical points of view. Nevertheless, in recent years, some observational and theoretical efforts have been made to find a solution. In this work we use the latest theoretical and computational tools to understand asymptotic {g}-mode pulsators: 1) the Frequency Ratio Method, and 2) Time Dependent Convection. With these tools, a self-consistent procedure for mode identification and modelling of these {g}-mode pulsators can be constructed. This procedure is illustrated using observational information available for the gamma Doradus star 9 Aurigae. [less ▲]

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See detailSUGAR-1 Spectrometry in Ultraviolet of GAlaxies at Redshift-1
Vandenrijt, Jean-François ULg; Alvarez, C.; Boschini, L. et al

in Final Papers, 56th IAC 2005, Fukuoka, Japan (2005)

This paper describes the outcome of the work performed during the 28th Alpbach Summer School, focused on the theme The Birth, Life and Death of Stars. We propose a mission consisting of a large aperture ... [more ▼]

This paper describes the outcome of the work performed during the 28th Alpbach Summer School, focused on the theme The Birth, Life and Death of Stars. We propose a mission consisting of a large aperture (3.5m main mirror diameter) UV space telescope, with capabilities for imaging and low, medium and high resolution spectroscopy. Even though such a telescope can have multiple scientific applications, we suggest a survey-type mission (SUGAR-1), dedicated mainly to the spectroscopic study of starburst galaxies at redshift z ~ 1, which corresponds to an epoch of enhanced star formation density in the history of the Universe and, in particular, to the time when our Solar System was born. Stars are the fundamental building blocks of galaxies. A major aspect of understanding galaxy formation and evolution is to understand their star formation history. Starburst galaxies are galaxies experiencing intense star forming activity and exhibiting strong UV emission from a young, hot stellar population. The study of starbursts helps us to understand the star formation process, and its influence on the environment and processes in the interstellar gas. The study of the star formation rate (SFR) at various redshifts is possible from the intensities of the H, H, OII and OIII lines, and the luminosity of the UV continuum. These can be used to generate Madau plots, which are diagnostic. Madau plots indicate that a peak of star formation in the history of the Universe occurred at z ~ 1, which corresponds to -5 Gyr, i.e. the moment of the birth of our own Solar System. Observations of this era will enable us to investigate the initial conditions in galaxies like ours when the formation was triggered. By observing a large number of galaxies at 0.4 < z < 1.1, we can learn about the properties of the star formation processes and the conditions of the interstellar medium (ISM) and its chemical properties at this moment of enhanced star formation. Spectroscopy and imaging in the UV will have a great impact on galaxy evolution modeling, since they will provide insight on whether the time corresponding to z = 1 was a time of massive galaxy formation, or if the massive star formation of that time took place in already established galaxies, which were formed at a much earlier stage in the evolution of the Universe. Moreover, studies of the Universe at z ~ 1 are of cosmological relevance, because according to the Cosmological Standard Model, it is precisely at z ~ 1 when the Universe underwent a phase transition from ΩMatter being larger than ΩDarkEnergy, to the opposite. Therefore, to investigate this interesting time in the evolution of the Universe, we suggest the construction of a dedicated UV telescope with a pre-defined science mission to perform Spectrometry in Ultraviolet GAlaxies at Redshift-1 (SUGAR-1). In what follows, a more detailed description of the mission science goals is given. We will show how the science goals are transformed into science requirements for the mission, which are turned into telescope and instrument requirements. Then a brief description will be given of the main technical aspects of the mission (spacecraft structure, electronics, power and orbit). The spacecraft mass and cost budgets of the mission are addressed, ending with a final summary. [less ▲]

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