Informations générales
Intitulé de l'offre : Measuring the masses of cold planets with Euclid and Roman M/F (H/F)
Référence : UMR7095-JEABEA-009
Nombre de Postes : 1
Lieu de travail : PARIS 14
Date de publication : vendredi 7 mars 2025
Type de contrat : Chercheur en contrat CDD
Durée du contrat : 24 mois
Date d'embauche prévue : 1 mai 2025
Quotité de travail : Complet
Rémunération : Approximately €3519 to €4291 gross per month, depending on experience.
Niveau d'études souhaité : Doctorat
Expérience souhaitée : 1 à 4 années
Section(s) CN : 01 - Interactions, particules, noyaux du laboratoire au cosmos
Missions
NASA's Roman space telescope, due to be launched in early 2027, will study dark energy and complete the statistical census of exoplanets with a large survey of gravitational microlenses towards the centre of our galaxy. Thanks to 432 days of observations spread over more than five years, Roman will detect more than 1,400 planets and provide the mass function of planets up to the mass of Mars, with sensitivity ranging from the habitable zone to very large orbits, even to unbound planets. While microlens light curves generally only give the star-planet mass ratio, Euclid's precursor observations ( on 23 and 24 March 2025) of Roman's fields will allow direct observation of the host star and the background source star, thus measuring the amplitude and direction of the relative proper motion, as well as the relative flows. This can be used as a strong constraint in the modelling of the light curve to measure the physical masses to 10%, from the first year of Roman.
Activités
The contract will focus on the analysis of Euclid data from Roman's fields, starting with obtaining the catalogue of point sources, then providing source-lens relative estimates for the ancient microlens events in this field discovered by OGLE and MOA (single, binary and planetary lenses) in order to derive a mass function for the lens population. The postdoctoral researcher will also work with the IAP team and Roman to develop the method of measuring mass using the relative source-lens movement between the Euclid (March 2025) and Roman (2027) observations. Important articles: - Bachelet E., et al. 2022, A&A 664, 136 - Kerins E., et al., 2023, arXiv:2306.10210 - Vandorou E., et al., 2020, AJ 160, 121 (for the mass measurement method)
Compétences
Doctoral thesis in astrophysics, good knowledge of Python, C, photometry, physics of gravitational microlenses.
Contexte de travail
This work will be carried out by the SPACE-MLENS team of the Institut d'Astrophysique de Paris, namely JP Beaulieu, C. Ranc, C. Alard, A. Cassan, P. Hudelot. We also work in close collaboration with our international partners from Euclid (in particular in Manchester and Salerno) and Roman (Goddard, University of Maryland, CALTECH-IPAC and Osaka).