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Exploration of the Outer Solar System : Serendipitous Occultations Françoise Roques (Observatoire de Paris). Beyond Neptune. A 10 km comet at 5000 AU . 200 meters TNO at 40AU. Beyond Neptune : an invisible world. KUIPER BELT. OORT CLOUD. Ground-based research
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Exploration of the OuterSolar System : Serendipitous Occultations Françoise Roques (Observatoire de Paris)
Beyond Neptune A 10 km cometat 5000 AU 200 meters TNO at 40AU
Beyond Neptune :an invisible world KUIPER BELT OORT CLOUD
Ground-basedresearch TAOS : T:0,5m + camera 10 Hz + 1000 stars (4 years) (Bianco et al. 2009) Ultracam : T:4-8m + camera 60Hz + 2 stars (100h) (Doressoundiram et al. 2012) Bickerton : T:2m + camera 40Hz + 2 stars (10h) (Bickerton et al. 2008) MMT :T4m+camera 10Hz+1000 stars (10h) (Bianco et al., 2009) PanStarrguiding camera : in prog. (Wang et al., 2010) Miosotys: T2m + camera 20Hz + 29 stars (2000h) : in prog(HTRA poster) UltraPhot : project of F-MOP instrument (Doressoundiram et al. 2013) Spatial research HSTguiding camera +40Hz (10 years) (Schlichting et al., 2009, 2012) RXTESco X-1(100h) (Chang et al. 2006, 2010) Corotsismology data (144 kh) :in prog. (HTRA poster) Whipple : project of NASA dedicated mission (Niheietal. 2009)
Structure of the Kuiper Belt Liu et al. in preparation Schlichting et al., 2009 Liu et al. in preparation
Structure of the Kuiper Belt Schlichting et al., in preparation Liu et al. in preparation
Kuiper Belt occultation rate N(radius>250m) = 107 deg-2 dt = 0.1 second => frequency > 20Hz dp = 20% => SNR > 100.f-1/2 occultations rate per star : 2500-1hours => Severaltarget stars and long runs
Oort Cloud exploration : Choice of target stars Target stars must be bright and verysmall : only 100 stars.deg-2
Fast Multi Object Photometer F-MOP multi-fiber instrument + large telescope + fast camera Fastsimultaneousaccurate (multi-color) photometryon severaltargets in a large field. stellar occultations, but also YSO, sdB stars, exoplanetstransits (Kepler field), cataclismic variables…
MEFOS, a 29 fibers spectrograph has been upgraded and and mounted on the 1.93m telescope of the OHP 29 image fibres 10 Hz see poster session
A flash star? dt = 0.05 second
A Fast Multi-Object Photometer : UltraPhot • UltrPhot, a high speed photometric mode on VLT2 • field : 25’ diameter • 60-80 fibres • fast camera (100 Hz)
Fast Multi Object Photometer F-MOP Fastsimultaneousaccurate (multi-color) photometryon severaltargets in a large field. stellar occultations, but also YSO, sdB stars, exoplanetstransits (Kepler field), cataclismic variables… Search collaborations for promotion of F-MOP
Beyond Neptune Françoise Roques, Bruno Sicardy, Thomas Widemann Alain Doressoundiram, FredericDauny, Paul Felenbok, Andrée Fernandez, Bernard Christophe, Jean Guerin, Stephen Shih, Joe Liu, Lucie Maquet (Lesia, Observatoire de Paris) Hsiang-Kuang Chang (Institute of Astronomy National Tsing Hua University, Taiwan) François Colas, Jean Lecacheux (Institut de Mécanique Céleste et de Calcul des Ephémérides, Observatoire de Paris)
UltraPhot - aperture size UltraCam data maximum diameter = 4.3’’
Two approachs size distribution? disk mass ? spatiale distribution ? Size ? Shape ? Atmosphere ? Satellites ?
Seeing mimics occultation events VLT/Ultracam : g’-r’ filters - f=65Hz dt=0.9 seconds depth = 7% stars separation : 79’’
Ground-based data : Miosotys 3780 hours Images dt= 0.5 sec 1-10 events : 0,3 – 1 km Data underanalysis see Poster Doressoundiram et al., in preparation
Spatial data : Corot data 144000 hours Images dt= 1sec 13 events : 0,5 – 1,5 km see Poster Liu et al., in preparation
Spatial data : RXTE/VGA data 70 hours Flux dt= 0.001 sec 1 event : 0,1km Chang et al. 2011