Fellowship galaxy formation and reionization, ExaSKAle project

Organisation/Company CNRS Department Observatoire astronomique de Strasbourg Research Field Astronomy Astronomy » Astrophysics Astronomy » Cosmology Researcher Profile First Stage Researcher (R1) Country France Application Deadline 19 Dec 2025 - 23:59 (UTC) Type of Contract Temporary Job Status Full-time Hours Per Week 35 Offer Starting Date 7 Sep 2026 Is the job funded through the EU Research Framework Programme? Not funded by a EU programme Is the Job related to staff position within a Research Infrastructure? NoOffer DescriptionThe ExaSKAle project aims to develop numerical simulation tools for studying the Reionization epoch and to produce models for interpreting observations of the intergalactic medium and the first galaxies during the first billion years of the Universe, whether with SKA (and its precursors) or JWST. The project is led by 2 teams from the Strasbourg Astronomical Observatory, D. Aubert (GALHECOs, P.I.) and P. Ocvirk (CDS, CoI) and is funded by the ANR for 2024-2028. At the end of the project's 48 months, the project will notably seek to produce models allowing prediction within a unified framework of both the large-scale IGM reionization properties and those of the reionization sources. This objective requires the production of large-volume and highly-resolved simulations, demanding in terms of computational resources and needing to be capable of using Exascale infrastructures. In this context, ExaSKAle seeks to recruit a postdoctoral collaborator (M/F) to help with the exploitation of the DYABLO code, a new astrophysical simulation platform for Exascale machines, developed by CEA and to which the Strasbourg Observatory contributes for its cosmological versions. This collaborator (M/F), expected for the last quarter of 2026 in Strasbourg, will need to contribute to the setup and production of large-scale reionization simulations.The collaborator (M/F) will contribute to setting up the modules allowing prediction of astrophysical observables from DYABLO outputs, such as UV luminosity functions and IGM statistics such as Lyman alpha opacity. The collaborator (M/F) will be responsible for calibrating sub-grid methods (for example stellar formation and feedback, AGNs), based on simulations of reduced size or resolution or zoom simulations, as part of preparing for the execution of very large simulations. The collaborator (M/F) will also be tasked with providing feedback on their use of the code to the developers and will be involved in modifications/extensions of the physics modules. The candidate must be capable of having strong mastery of a dual aspect, both numerical and astrophysical.The postdoctoral collaborator (M/F) will be integrated into the CDS team of the Strasbourg Astronomical Observatory and will work under the direction of P. Ocvirk, in collaboration with the other members of ExaSKAle, O. Marchal (CNRS Research Engineer, GALHECOS) and D. Aubert (Professor, GALHECOS). The Astronomical Observatory is a joint research unit (UMR) of CNRS and the University of Strasbourg, located in the heart of the city's historic campus. It comprises approximately 100 people, including about 30 permanent scientists whose main themes are galaxy physics, high-energy astrophysics, as well as data science for astronomy. The ExaSKAle project has its own computing resources for development and analysis, including a state-of-the-art GPU server. It also has very regular access to national and international computing facilities. The collaborator (M/F) will have the computing and financial resources necessary to carry out their mission. They will also be required to undertake missions or participate in conferences.The collaborator (M/F) must hold a doctorate in astrophysics and have demonstrated experience in handling and/or developing numerical tools for astrophysics. This includes simulation but also the implementation of analysis tools, or modeling tools involving numerical computation. Experience in C++, Python, GPU programming and in the use of large-scale computing facilities is desired. Mastery of English at B2 level according to the Common European Framework of Reference for Languages is required. #J-18808-Ljbffr