Accueil du site > Offres d’emploi > Stages et thèses > PhD thesis project "Towards the detection of short period planets embedded in the circumstellar disk of young stars"



OSUG - Terre Univers Environnement OSUG

PhD thesis project "Towards the detection of short period planets embedded in the circumstellar disk of young stars"

The recent discovery by the Kepler satellite of many super-Earth and mini-Neptune-like planets in orbit very close to their star (0.1 astronomical units or a few stellar radii) raises the question of their formation. The aim of the proposed thesis is to exploit different observational approaches in an attempt to detect short-period proto-planets during their formation phase, while they are still embedded in the inner regions of the circumstellar disc. In particular, the photometric and spectroscopic variability of Tauri T-type systems will be studied jointly to search for embedded planetary signal signatures. The study will focus on a few systems for which Kepler-K2 light curves and simultaneously obtained spectropolarimetric data from the Canada-France-Hawaii telescope with the ESPADONS and soon SPIROU are available. The unparalleled quality of these datasets provides the ability to probe the inner regions of the circumstellar disc and to characterize the associated physical processes, including the interaction between the inner edge of the disc and the stellar magnetosphere, ultimately attempting to detect the trace of the presence of an embedded planet. The thesis is part of the ERC Advanced Grant project "SPIDI : Star-Planet (s) -Inner Disk Interactions" (2018-2022), which combines various observational approaches and the development of numerical models for the search and characterization of proto-planets embedded at the inner edge of the circumstellar discs of young stars. The observational data (light curves, spectral series) will be provided by the host team at IPAG. The work of thesis will consist in applying and / or developing the analytical tools and models necessary for their astrophysical interpretation. The proposed approach is currently the only one that can probe the inner region of the disk, at less than 0.1 AU from the star. This thesis will provide unique constraints on the structure of the inner disc of young stars and on the perturbations induced by the presence of super- Earth and mini-Neptune planets in the course of formation.

The thesis will be jointly supervised by Jérôme Bouvier (ERC SPIDI project principal investigator) and Evelyne Alécian at IPAG. The former is a specialist in the variability of young stars and the process of magnetospheric accretion. He will supervise the thesis for the analysis and interpretation of light curves and spectral series. The latter has the necessary expertise to supervise the analysis of the spectropolarimetric data for the determination of the magnetic topologies of young stars.

The thesis will take place at IPAG, the laboratory offering all the necessary means for the smooth running of the thesis. The student will be integrated into the vast network of national and international collaborations that underpin the ERC SPIDI project. This will lead him/her to make regular visits to project staff in Europe and beyond, thus offering him/her a global panorama of astrophysical research and numerous contacts for the continuation of his/her career. Funding for the thesis allocation and the associated research budget (conferences, visits, observation missions, etc.) is allotted to the ERC SPIDI project.

The subject involves a significant investment in observational data analysis. Any knowledge in languages and analysis tools (Linux, Python, IDL, Topcat, statistical methods, spectral analysis, photometric analysis, etc.) is welcome. Candidates are kindly requested to submit a file containing : a CV, a cover letter, a transcript of their pre-doctoral degree, and possibly letters of recommendation to the following address : Jerome.Bouvier univ-grenoble-alpes.fr

Bibliography :

Alecian, E., and 9 colleagues \ 2013.\ A high-resolution spectropolarimetric survey of Herbig Ae/Be stars - I. Observations and measurements.\ Monthly Notices of the Royal Astronomical Society 429, 1001-1026.

Bouvier, J., Alencar, S. H. P., Harries, T. J., Johns-Krull, C. M., Romanova, M. M.\ 2007.\ Magnetospheric Accretion in Classical T Tauri Stars.\ Protostars and Planets V 479-494.

Bouvier, J., and 10 colleagues 2007.\ Magnetospheric accretion-ejection processes in the classical T Tauri star AA Tauri.\ Astronomy and Astrophysics 463, 1017-1028.

Cody, A. M., and 44 colleagues 2014. CSI 2264 : Simultaneous Optical and Infrared Light Curves of Young Disk-bearing Stars in NGC 2264 with CoRoT and Spitzer : Evidence for Multiple Origins of Variability. The Astronomical Journal 147, 82.

Useful links :

ERC SPIDI : http://cordis.europa.eu/project/rcn...

Kepler-K2 : https://keplerscience.arc.nasa.gov/

CFHT/Espadons : http://www.cfht.hawaii.edu/Instrume...

CFHT/Spirou : http://www.cfht.hawaii.edu/en/proje...

Sous la tutelle de:


Sous la tutelle de:

CNRS Université Grenoble Alpes