GAIA - RRFWG Nice, November 2003

Transcription

1 Relativity and Reference Frame Working Group 4th Meeting F. Mignard 1

2 Attendants Alexandre Andrei Jos de Bruijne Maria Teresa Crosta Agnes Fienga Daniel Hestroffer Sergei A. Klioner Jean Kovalevsky Mario G. Lattanzi Christophe Leponcin-Lafitte Francois Mignard Sophie Pireaux Eric Slezak Alain Smette Pierre Teyssandier J. Torra Alberto Vecchiato 2

3 AGENDA 27/11 09h00 Status of the GAIA mission. Current activities F. Mignard 09h30 Organisation of the WG. Webpages. Actions. F. Mignard Information sheets. 09h50 Parameters data base J. de Bruijne 10h00 Implementation of the GAIA PPN astrometry model S. Klioner 10h30 Coffee 11h00 Comparison of two implementations of the PPN model J. Torra 11h30 Lenses in GAIA QSOs A. Smette, J.F. Claesckens 12h00 Short update on the galactic aberration J. Kovalevsky 12h15 lunch break 14h00 Implementation of the ephemris in GDAAS F. Mignard 14h15 Ephemeris of the solar system. Comparison DE403/405 A. Fienga, J.L. Simon 14h45 The GAIA centre of mass reference system S. Klioner 15h15 Close approaches between bright stars and planets F. Mignard 15h45 coffee 16h15 Relativistic attitude for GAIA M.T. Crosta, D. Bini et al. 16h45 The RAMOD model : an update A. Vecchiato et al. 17h15 Open discussion on the variouse approaches 17h30 World function and muas astrometry P. Teyssandier, Ch. Leponcin 18h00 End of the first day 3

4 AGENDA 28/11 09h00 Comments on the WG webpages A. Vecchiato 09h15 The RAMOD model : an update A. Vecchiato et al. 09h45 World function and muas astrometry P. Teyssandier, Ch. Leponcin 10h15 Status on the creation of the QSO synthetic spectra A. Smette, J.F. Claeskens 10h45 Coffee 11h15 Photometric recognition of QSOs A. Smette, J.F. Claeskens 11h45 Status of the B1.0 and GSC.2 simulation of the EGRF A. Andrei, E. Slezak,A. Fienga 12h15 13h30 Lunch break End of the meeting 13h30 Determination of QSO parameters A. Smette, J.F. Claeskens 14h00 General discussion, next meeting, actions 15h00 End of the meeting all 15h15 Taxi departure 4

5 Objectives of the meeting Status of the GAIA mission Status of the actions agreed on Review of the on-going activities Set guidelines for the next six months 5

6 Information sheets 6

7 GAIA Information Sheets Structure of the GAIA web site in ESTEC : three levels = - ESA portal directed to general public - ESA SciTech Portal : inform on the scientific missions for scientific community, industry - RSSD website : Active web site for the project scientist and the GAIA community Content for gaia : project status, key papers, access to relevant sites, resources for presenting gaia, meetings, information sheets Main person in charge : Karen O'Flaherty (koflaher@rssd.esa.int) 7

8 GAIA information sheets Content of an information sheet : -a ~ 400 words informative text on a specific topic - One or two illustrations at the top of the page - Extended caption Requested topics for the RRFWG : L2 orbit :: Done (F.Mignard) WG in general :: in progress (F.Mignard) Quasars :: Done( JFClaeskens) Light bending :: Done (JdBruijne) Microlensing :: ( W.Evans) 8

9 The Relativity and Reference frame Working Group 9

10 Objectives of the WG Identify the relevant space-time effects to 1µas for stars and planets Modelling the observations at this lever of accuracy in a consistent way relativistic definition of parallax, proper motion, radial velocity Ensure that IAU/IERS standards are met when possible Make the necessary recommandations to help the implementation reference frame time scales solar system and satellite ephemeris Investigate the determination of fundamental physics parameters PPN parameters others? Investigate the definition and realisation of the inertial frame with GAIA source selection residual spin zero point Astrometric and photometric lensing? 10

11 Membership Core members B. Bucciarelli M.T. Crosta F. DeFelice D. Hestroffer S. Klioner M. Lattanzi L. Lindegren F. Mignard J.L. Simon A. Smette M. Soffel A. Vecchiato Associates G. Anglada L. BLanchet J. F. Claesckens J. de Bruijne W. Evans A. Fienga E. Grebel J. Torra J. Kovalevsky Ch. Leponcin-Lafitte S. Pireaux I. Roxburgh P. Royer J. Souchay E. Slezak J. Surdej P. Teyssandier 11

12 Activities Tasks identified Leader Relativistic modelling - Software development M. Lattanzi - Model development S. Klioner - Simulation A. Vecchiato Reference system - QSO detection A. Smette - ICRF F. Mignard - Earth and planetary Ephemeris J.L. Simon 12

13 Web Pages Developped and maintained by A. Vecchiato user : jupiter pwd : Nomads Developped and maintained by A. Vecchiato should be an active area link or main repository for meeting presentations Example : Dresden meeting 13

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15 Review of pending actions 15

16 The RRFWG and Lensing Three kinds of lensing to be considered mirco-lensing by Milky-way stars micro-lensing by stars of external galaxies macro-lensing by galaxies Signatures with GAIA positional (mas for µlensing to arcsec for Mlensing) photometry ( ~ mag amplitude) time scale (~ month for µlensing to ~ 10 years for Mlensing) imaging Scientific case positional noise for QSOs FM 06/03, AS 11/03 survey of lenses from QSO lensing, cosmology JS 12/02 detection of brown dwarfs masses of lenses Activities within the RRFWG assessement of the effects astrometric detection? relation with other WGs on this topic 16