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Participant |
Crosta, Mariateresa | |||||||
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Institution |
INAF-OATo - Via Osservatorio 20 - Turin - - Italy | |||||||
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Session |
PT2 |
Accepted |
Yes |
Order |
11 |
Time |
17:30 | 15' |
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Talk |
Oral abstract |
Title |
RELATIVISTIC LIGHT TRACING IN THE GAIA ERA | |||||
| Coauthors | Crosta, M.; Vecchiato, A.; de Felice, F.; Lattanzi, M.G. | |||||||
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Abstract |
Mission like Gaia (ESA, launched on December 19, 2013) requires to treat gravity properly when compiling stellar positions and proper motions. In this talk we present the analytical solution for light propagation conceived to suit the accuracy achievable by Gaia consistently with the measurement protocol in General Relativity as adopted within the RAMOD framework. Aim of RAMOD is to provide a general relativistic tools for the science exploitation of such a revolutionary mission, whose main goal is to trace back star directions from within our local curved space-time, therefore providing a three-dimensional map of our Galaxy. The results are useful for a thorough comparison and cross-checking validation of what already exists in the field of Relativistic Astrometry. Moreover, the method of measurements in GR introduced by RAMOD extends beyond the scope of Gaia: the analytical solutions can be applied to other measurements that require the same order of accuracy as that one expected for Gaia. |
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Pdf file |
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Session |
PT5 |
Accepted |
Yes |
Order |
9 |
Time |
17:05 | 20' |
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Talk |
Oral abstract |
Title |
GRAVITATIONAL ASTROMETRY FROM WITHIN THE SOLAR SYSTEM | |||||
| Coauthors | Crosta,M; Lattanzi, M.G; Vecchiato, A.; Abbas, U. | |||||||
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Abstract |
Mission like Gaia (ESA, launched in 2013) requires to treat gravity properly when compiling microsecond stellar catalogues, and promotes the use of highly accurate astrometry to help scrutinize among several alternative theories the one providing the route to quantum gravity or also to test locally current cosmological models. Gaia will be able to carry out general relativistic tests by means of both global and differential astrometric measurements. This will open a unique opportunity to put in practice methods of relativistic astrometry mainly devoted to model the celestial sphere with the percepts of General Relativity (GR). Global tests will be done through the full astrometric reconstruction of the celestial sphere, while the differential experiments will be implemented in the form of repeated Eddington-like measurements. After almost one century, Gaia will perform the largest experiment in GR ever made with astrometric methods (since 1919): a relativistic all-sky reconstruction which includes also QSO at different redshifts. Moreover, at zero redshift, dealing with local cosmology, accurate absolute motions of stars within our Galaxy will provide access to the cosmological signatures in the disk and halo. |
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Pdf file |
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