PASTIS · Planet Analysis and Small Transit Investigation Software
FP7 — People (Marie Curie Actions)
- Duration
- 2014-10-01 → 2016-09-30
- EU contribution
- €153,330
- Participants
- 1
- Scheme
- MC-IEF
Lines connect the coordinator with its partners.
Results in brief
Planet Analysis and Small Transit Investigation Software
Small planets orbiting other stars are difficult to find. Their astrophysical signature might be mimicked by different other sources, biasing their interpretation. The PASTIS (Planet Analysis and Small Transit Investigation Software) is a unique European code that aims at determining if a planetary signal, detected by state-of-the-art space missions or ground-based instruments, is actually a planet or not. This validation procedure is however limited by the lack of knowledge on the host star or by its intrinsic variability. To improve the validation capabilities of the PASTIS tool, in particular towards small planets in the habitable zone of their star, this MSCA project aims at: (1) implementing new constraints about the host star, in particular the result from asteroseismology (stellar density) (2) implementing new models to account for stellar variability (such as spots, plages, granulation, magnetic cycles) The upgrade of PASTIS is needed to be ready to validate small planets that will be detected by the next-generation instruments like the ESPRESSO (ESO / VLT) and the PLATO space mission (ESA). At the end of this MSCA project, the new developments have been implemented and tested. Using the asteroseismic constraints on the host star substantially improves the validation efficiency. This has already been used for a design study of the PLATO mission. A model for stellar activity (SOAP) has been fully implemented. However, during the test phase, it turns out that the complexity added by this new model substantially increased the computing time, as such as the code could not be used anymore within a reasonable amount of time (a week). Hence, another approach has been explored: such as Gaussian Process. This new approach allows to model stellar activity "noise" as long as this noise is coherent (hence producing a correlated noise). It has been applied to the test case of CoRoT-7. The PASTIS software was used to validate about a dozen of planets, down to the size of the Earth, from the Kepler, K2, and Super-WASP surveys. During the two years of this project, the fellow published 35 papers as first author or co-author and gave talks or invited review in 14 international conferences and seminars.
Data: CORDIS, © European Union
Project objective
Detection and characterization of extrasolar low-mass planets are currently limited by several astrophysical and instrumental effects. New exoplanet-hunter instruments, with improved capabilities, are foreseen at the horizon 2016 - 2017. To find other Earths, new state-of-the-art instruments must be followed by the state-of-the-art of data analysis software that takes into account for the astrophysical limitations. Currently, the main astrophysical limitations to the detection and the precise characterization of exoplanets are the precise characterization of the host star and the existence of false-positive scenarios (such as diluted binaries or stellar activity which are able to mimic extrasolar planets. The objective of this proposal is double. First, implement into the PASTIS software (a state-of-the-art of data-analysis software, co-developed by the candidate) tools to both characterize the planet-host star and to model stellar jitter. This will be done with the help of world-leading experts present at the host institution. The second objective is to validate new small and low-mass planets among the CoRoT, Kepler and HARPS data, using the improved PASTIS software. These developments and detections will be a milestone for the detection capabilities and analysis of data currently collected at the host institution and for the search of exo-Earths with future facilities, in which Europe always played a pioneer role.
Original text from CORDIS.
Participants
- CENTRO DE INVESTIGACAO EM ASTRONOMIA E ASTROFISICA DA UNIVERSIDADE DOPORTO ASSOCIACAO · PortoCoordinatorPortugal
Links
Data: CORDIS, © European Union