Daniel Rouan

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Daniel Rouan, born on 21 September 1950, is a French astrophysicist. He is Director of Research Emeritus at the CNRS. He was elected to the French Academy of Sciences in 2005. [1]

Contents

Biography

Daniel Rouan, a former student of the École normale supérieure (1970-1974), agrégé de sciences physiques (1974), doctor of science (1982), is Director of Research Emeritus CNRS at LESIA, [2] the space laboratory of the Observatoire de Paris, where he has conducted most of his career. [3]

Scientific work

He focused his instrumental research on the development of infrared astronomy in France, on the ground [4] and in space, and more particularly on high angular resolution and high contrast imaging by contributing to the development of adaptive optics, which corrects the harmful effects of atmospheric turbulence and stellar coronography, which make it possible to mask the light of a star to better distinguish its planetary environment. He is the inventor of the four-quadrant coronograph, [5] installed on several telescope instruments on the ground or in space.

Involved in the development of several space projects (ISO, CoRoT, JWST) or instruments for very large ground-based telescopes (VLT-NAOS, VLT-SPHERE), he uses these techniques to discover and study exoplanets: [6] he is thus co-discoverer of about forty extrasolar planets, including COROT-7b, the first rocky exoplanet detected, [7] as well as the giant planet directly around the star beta Pictoris. [8]

He also studies the physics of the interstellar medium [9] [10] [11] [12] [13] and circumstellar, [14] the regions of intensive star formation and the environment of active galaxy nuclei. [15] In particular at the centre of the Milky Way, as part of an international team, he provided definitive proof of the existence of an ultra-massive black hole 4 million times the mass of the sun. [16] [17]

He founded the concept of Diophantine optics, [18] several versions of which [19] have been tested and validated. He has published more than 470 articles, 215 of which are in range A newspapers [20] and is co-author of several books:

Honours and awards

Related Research Articles

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References

  1. 1 2 "Académie des sciences".
  2. ↑ "LESIA".
  3. ↑ "Page DR".
  4. ↑ Delfosse, Xavier; et al., "Field brown dwarfs found by DENIS", A&A , 1997, 327, p. L25
  5. ↑ Rouan, Daniel; Riaud, Pierre; Boccaletti, Anthony; Clénet, Yann; Labeyrie, Antoine; "The Four-Quadrant Phase-Mask Coronagraph. I. Principle", PASP , 2000, 112, p. 1479, doi: 10.1086/317707
  6. ↑ Léger, Alain; Mariotti, Jean-Marie; Mennesson, Bertrand; Ollivier, Marc; Puget, Jean-Loup; Rouan, Daniel; Schneider, Jean; "Could We Search for Primitive Life on Extrasolar Planets in the Near Future?", Icarus , 1996, 123, p. 249
  7. ↑ Léger, Alain; Rouan, Daniel; Schneider, Jodi; Barge, Pierre; Fridlund, Malcolm; et al., "Transiting exoplanets from the CoRoT space mission - VIII. CoRoT-7b: the first Super-Earth with measured radius", A&A, 2009, 506, p. 287
  8. ↑ Lagrange, Anne-Marie; Gratadour, Damien; Chauvin, Gaël; Fusco, Thierry; Ehrenreich, David; Mouillet, David; Rousset, Gérard; Rouan, Daniel; et al., "A probable giant planet imaged in the beta Pictoris disk. VLT/NaCo deep L'-band imaging", A&A, 2009, 493, p. L21
  9. ↑ Rouan, Daniel; Léna, Pierre; Puget, Jean-Loup; de Boer, Klaas S.; Wijnbergen, Jan J.; "Far infrared observations of the galactic plane and molecular cloud S140", Ap. J. , 1977, 213, p. L35-39
  10. ↑ Rouan, Daniel; "Statistical distribution of the interstellar dust temperature", A&A,, 1980, 87, p. 169
  11. ↑ Rouan, Daniel; Field, D.; Lemaire, J.-L.; Lai, O.; Pineau Des Forêts, G.; Falgarone, E.; Deltorn, J.-M.; "The power of adaptive optics: a close look at a molecular cloud in NGC 2023", MNRAS , 1997, 284, p. 395
  12. ↑ Rouan, Daniel; Léger, Alain; Le Coupanec, Patricia; "Carrier of the λ 5797 DIB in the ISM and in the Red Rectangle: a suprathermally rotating PAH molecule?", A&A, 1997, 324, p. 661
  13. ↑ Rouan, Daniel; Léger, Alain; Omont, Alain; Giard, Martin; "Physics of the rotation of a PAH molecule in interstellar environments", A&A, 1992, 253, p. 498
  14. ↑ Dougados, Catherine; Rouan, Daniel; Léna, Pierre; "Measure of the grain velocity structure in the circumstellar envelope 'Frosty Leo'", A&A, 1992, 253, p. 46
  15. ↑ Rouan, Daniel; Lacombe, François; Gendron, Éric; Gratadour, Damien; Clénet, Yann; Lagrange, Anne-Marie; Mouillet, David; Boisson, Catherine; et al., "Hot Very Small dust Grains in NGC 1068 seen in jet induced structures thanks to VLT/NACO adaptive optics", A&A, 2004, 417, p. L1
  16. ↑ Schödel, Rainer; Ott, Thomas; Genzel, Reinhard; et al., "A star in a 15.2 year orbit around the supermassive black hole at the center of the Milky Way", Nature , 2002, 419, p. 694
  17. ↑ Genzel, Reinhard; Schödel, Rainer; Ott, Thomas; Eckart, Andreas; Alexander, Tal; Lacombe, François; Rouan, Daniel; "Near-IR Flares from Accreting Gas near the Last Stable Orbit around the Supermassive Black Hole in the Galactic Centre", Nature, 2003, 425, p. 934
  18. ↑ "Optique diophantienne".
  19. ↑ Rouan, Daniel; Pelat, Didier; "The achromatic chessboard, a new concept of a phase shifter for nulling interferometry. I. Theory", A&A, 2008, 484, p. 581
  20. ↑ "Google Scholar".
  21. ↑ "La Main à la pâte".
  22. ↑ Décret du 13 juillet 2019 portant promotion et nomination
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