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Annual Report 2008 Koninklijke Sterrenwacht van België Observatoire royal de Belgique Royal Observatory of Belgium Mensen voor Aarde en Ruimte , Aarde en Ruimte voor Mensen Des hommes et des femmes pour la Terre et l'Espace, La Terre et l'Espace pour l'Homme Jaarverslag 2008 Rapport Annuel 2008 Annual Report 2008 De activiteiten beschreven in dit verslag werden ondersteund door Les activités décrites dans ce rapport ont été soutenues par The activities described in this report were supported by De POD Wetenschapsbeleid / Le SPP Politique Scientifique De Nationale Loterij La Loterie Nationale De Europese Gemeenschap Het Europees Ruimtevaartagentschap La Communauté Européenne L’Agence Spatiale Européenne Het Fond voor Wetenschappelijk Onderzoek Le Fonds de la Recherche Scientifique – Vlaanderen Le Fonds pour la formation à la Recherche dans l’Industrie et dans l’Agriculture (FRIA) Instituut voor de aanmoediging van innovatie door Wetenschap & Technologie in Vlaanderen Privé-sponsoring door Mr. G. Berthault / Sponsoring privé par M. G. Berthault 2 Deel 1: Wetenschappelijke activiteiten Partie 1: Activités Scientifiques Part 1: Scientific Activities 3 4 Summary Abbreviations.................................................................................................................................. 7 A. GNSS Positioning and Time............................................................................................. 14 A.1. Time and Time transfer .............................................................................................................15 A.2. GNSS positioning......................................................................................................................20 B. Earth and planet rotation and interior............................................................................. 28 B.1. Planets........................................................................................................................................29 B.2. Earth rotation and interior..........................................................................................................50 C. Publications....................................................................................................................... 55 D. Seismology, seismic hazards and risks, earthquake monitoring..................................... 66 D.1. Project « Seismology, seismic hazards and risks »....................................................................66 D.2. Project « Seismic monitoring » .................................................................................................80 E. Gravimetry......................................................................................................................... 85 E.1. Project « Gravimetry and geodynamics »..................................................................................85 F. Publications....................................................................................................................... 92 G. Asteroids ............................................................................................................................ 97 G.1. Project "RUSTICCA"................................................................................................................97 H. Digitization ...................................................................................................................... 100 H.1. Project "Digitization of the heritage of the federal scientific institutes of Belspo".................100 H.2. Project UDAPAC ....................................................................................................................106 I. Publications......................................................................................................................... 106 J. Binaries ............................................................................................................................... 109 J.1. Project "Visual Binaries - Binaries and Multiple Stars"..........................................................109 K. Asteroseismology............................................................................................................. 111 K.1. Asteroseismology of single, binary or multiple stars ..............................................................111 K.2. Stellar characterization ............................................................................................................117 K.3. Asteroseismology from space missions: CoRoT, Kepler ........................................................121 L. Instrumentation .................................................................................................................. 125 L.1. The spectrograph HERMES ....................................................................................................125 L.2. Humain Observatory for Astrophysics of Coeval Stars (HOACS) .........................................126 M. Publications..................................................................................................................... 127 N. Stellar winds and circumstellar structures..................................................................... 135 N.1. Hot stars...................................................................................................................................135 N.2. AGB stars ................................................................................................................................139 N.3. Post-AGB stars and Planetary Nebulae...................................................................................141 N.4. The Photoionization Code Cloudy ..........................................................................................145 N.5. The Atomic Line List ..............................................................................................................146 O. Variable Stars.................................................................................................................. 148 O.1. γ Doradus stars observed with the Mercator telescope............................................................148 O.2. Cepheids ..................................................................................................................................149 O.3. Analysis of data from the CoRoT satellite ..............................................................................150 O.4. Research project: Kepler .........................................................................................................152 P. Binary stars......................................................................................................................... 152 P.1. Binary Stars in young stellar groups........................................................................................152 Q. Distance scale in the local universe ............................................................................... 154 Q.1. Mean absolute magnitudes of Red Clump stars ......................................................................154 R. Atomic Data for Spectral Standard Stars....................................................................... 155 R.1. The SpectroWeb Database.......................................................................................................155 S. Solar Spectroscopy.............................................................................................................. 156 5 S.1. Solar Abundances and relevant Spectroscopic Data ...............................................................156 T. Publications......................................................................................................................... 158 U. Solar atmosphere, heliosphere and space weather research......................................... 163 U.1. Physical processes and modeling ............................................................................................163 U.2. Investigations of the solar atmosphere from spectroscopic diagnostics..................................167 U.3. Investigations of the solar atmosphere from disc images or time series..................................169 U.4. Coronagraphic, radio and in-situ investigations in the heliosphere.........................................174 V. Solar Instrumentation..................................................................................................... 184 V.1. Design and construction of radiotelescopes in the HUMAIN station .....................................184 V.2. Improvements of ROB solar telescopes (USET).....................................................................188 V.3. SWAP......................................................................................................................................192 V.4. LYRA ......................................................................................................................................194 V.5. Solar space technologies..........................................................................................................197 V.6. Solar Orbiter and EUI..............................................................................................................200 W. Instrument operations, data handling and services....................................................... 202 W.1. Solar optical observations (Uccle Solar Equatorial Table)......................................................202 W.2. Solar radioelectric observations at the Humain
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