Archives Séminaires 2016-2017

Séminaire

Séminaire IPAG de Carine Babusiaux (GEPI), jeudi 13 avril 2017 à 11h00, IRAM seminar room

Gaia is an ESA astrometric mission launched end of 2013. After its five years of observations, it will provide unprecedented astrometry (parallaxes and proper motions) for more than 1 billion stars brighter than G=20.7 mag. It will also provide spectrophotometry for all those stars and radial velocities for the brightest ones. By providing 3D spatial and velocity distributions of the stars combined with their astrophysical properties, Gaia will revolutionize our knowledge of the Milky Way (…)

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Séminaire IPAG de Claudio Codella (INAF, Osservatorio di Arcetri), jeudi 4 mai 2017 à 11h00, IRAM seminar room

The birth of a Sun-like star is a complex game played by several participants whose respective roles are not yet entirely clear. On the one hand, the star-to-be accretes matter from a collapsing envelope. The gravitational energy released in the process heats up the material surrounding the protostar, creating warm regions enriched by interstellar complex organic molecules (iCOMs, at least 6 atoms) called hot corinos. On the other hand, the presence of angular momentum and magnetic fields (…)

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Séminaire IPAG de Guilaine Lagache (LAM), jeudi 18 mai 2017 à 11h00, IPAG seminar room

The fine structure line [CII] at 158 microns is one of the brightest emission lines in the spectra of galaxies. It is considered to be the dominant coolant for neutral atomic gas in the interstellar medium. Conveniently, [CII] is redshifted into the sub-millimeter and millimeter atmospheric windows for 4.56). However, so far, [CII] studies of very distant galaxies have been limited, with detection of only a handful of galaxies. The full power of ALMA will revolutionize the field, detecting (…)

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Séminaire IPAG de A.S. Brun (DAp/AIM, CEA- Paris-Saclay) , jeudi 8 juin 2017 à 11h00, IPAG seminar room

With more than 3000 exo-planetary systems discovered as of today including more than 500 planets orbiting very close (within 10 stellar radii) to their host star, it is now becoming urgent to characterize star-planet interactions for such close-in systems. Extending our knowledge of the solar system and Sun-Earth relationships to these quite different exo-systems requires to develop theoretical and numerical tools that can deal with the large diversity of stellar rotation rates, activity (…)

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Séminaire IPAG de Bertrand Lefloch (IPAG), jeudi 15 juin 2017 à 11h00, IPAG seminar room

The conditions for planet formation and the emergence of life is one of the key-questions in modern astrophysics. Thanks to the recent spectacular progress in radioastronomical observations, we are now in position to address the question of our ``chemical origins", namely to understand the evolution of matter and molecular complexity during the long process that brought it from prestellar cores, to protostars, protoplanetary disks, and ultimately to the bodies of the Solar system.
Spectral (…)

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Séminaire IPAG de Andrea Chiavassa (Laboratoire Lagrange), jeudi 22 juin 2017 à 11h00, IPAG seminar room

Nowadays, the development of the observational instruments is so high that became very sensitive to the details of stellar surface. The interpretation of the stellar surfaces images, the fundamental parameters, the stellar variability and the planet detection needs realist simulations of stellar convection. Three-­dimensional radiative hydrodynamics simulations of cool stars are essential to a proper and quantitative analysis of these observations. I will present how these simulations across (…)

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Séminaire IPAG de Karine Perraut (IPAG), jeudi 29 juin 2017 à 11h00, IPAG seminar room

GRAVITY is the second generation Very Large Telescope Interferometer (VLTI) instrument of ESO for precision narrow-angle astrometry and interferometric imaging. Designed to probe physics close to the event horizon of the Galactic Centre black hole, it operates in the near-infrared K band and takes benefit of the unique potential of the VLTI, with its four 8-meter Unit Telescopes (UTs) for high angular resolution imaging at high sensitivity, and with its 2-arcsecond field for providing (…)

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Séminaire IPAG de Philippe Boduch (CIMAP), jeudi 6 juillet 2017 à 11h00, IPAG seminar room

Since 2008, a CIMAP-GANIL team has studied irradiation of ice of astrophysical interest with swift heavy ions. These ices are mainly composed of simple molecules such as H2O, CO, CO2, NH3 ... Ices are ubiquitous in space. They are present on comets, satellites of certain planets (Jovian moons for example) and on the grains the dense clouds in ISM. These ices can be irradiated in space by UV photons, stellar winds or cosmic rays. Proton and UV irradiations have been the subject of numerous (…)