Emplois, stages

Place of employment : The candidate will work in the "Heliosphere and Astrophysical Plasmas" pole of the LESIA laboratory of Paris Observatory, on the Meudon site, 5 km south-west of Paris.

The search and study of radio emissions from exoplanets is a hot topic at the crossroads of modern radio astronomy and planetary physics. The post-doctoral contract is proposed in the frame of the ERC (Advanced Grant) project EXORADIO, led by Philippe Zarka at Paris Observatory, which aims to detect these emissions at very low frequencies with NenuFAR, the new very large low frequency radio telescope (10-85 MHz) developed at Paris Observatory. This telescope, which is both complementary to and compatible with LOFAR, starts its scientific operations this year. Within the NenuFAR consortium, the EXORADIO team currently involves 3 researchers and 1 engineer (part-time) and 1 PhD student, combining expertise in low frequency radio astronomy, planetology and plasma physics. The post-doctoral fellow will work closely with the NenuFAR imaging team. The EXORADIO team will be further reinforced by a second post-doc and a second PhD student. The beamformed data exploitation pipeline, as well as a pre-processing pipeline (flagging+averaging) of NenuFAR imaging data, are operational. The imaging data are standard Measurement Sets, whose calibration and imaging use software developed for LOFAR or other radio telescopes.

Contribute to the development, fine-tuning and testing of the calibration and imaging pipeline for the NenuFAR low-frequency radio telescope (https://nenufar.obs-nancay.fr), up to the production of dynamic spectra (time-frequency planes) synthesized on a catalogue of exoplanetary sources. Analyse, with the help of this pipeline, the images and dynamic spectra acquired in the frame of the "Exoplanets" key programme of NenuFAR. Characterise the radio emissions detected, and participate in their physical interpretation.

The activities will initially consist in the selection and assembly of existing softwares (DI & DD calibrations, beam model...), their optimisation and testing, to develop an operational pipeline delivering image cubes and dynamic spectra with NenuFAR. This pipeline, potentially optimized for grid computing, containerized and deployed on the (future) NenuFAR Data-Center, will then be intensively exploited to analyze end-to-end NenuFAR exoplanet observations.

Constraints : Occasional visits will be made to the Nançay Radio Observatory, NenuFAR site (200 km south of Paris), for meetings or busy weeks. Participation in national and international conferences and symposia to present the results obtained will be encouraged (the Exoradio project includes a budget for missions). The nature of the contract requires full-time dedication to the Exoradio project ; it does not include the possibility of using a fraction of the research time outside the project.

Good expertise in interferometry (calibration and imaging) is desired, with experience in instrument commissioning and/or algorithmic developments aimed at optimising images and dynamic spectra produced from interferometric data. Experience in using the LOFAR instrument in interferometric mode (and in reducing its data) is an advantage. Python language skills are required. Ability to work in a team is essential, as is fluency in English or French (written and spoken). Skills in writing and communicating research results are welcome. a PhD in astrophysics or a related discipline (physics, signal processing, applied maths...) is required. Previous post-doctoral experience is welcome but not required.

The application requires a full scientific CV and a letter of motivation, to be submitted on the CNRS job portal. One or two letters of recommendation describing previous work are welcome but optional (to be sent directly by the referees). A practical test will be organised on interferometric data during the interview.

https://emploi.cnrs.fr/Offres/CDD/UMR8109-SYLDES-041/Default.aspx