Missions

The overall objective of the ANR speXion project (managed by AIM, the University of Geneva, and the Institut d'Astrophysique de Paris) is to conduct a coherent study of extremely metal-poor galaxies to understand the radiation field dominating these galaxies up to X-rays, characterize the nature and influence of energetic sources and associated feedback processes, and understand the contribution of these galaxies to cosmic reionization.

Within this framework, AIM offers a postdoctoral contract to conduct a coherent study to deduce the nature of sources (more or less massive X-ray binaries, intermediate-mass black holes, supermassive black holes...) present in a specific sample of galaxies through the signatures of the irradiated interstellar medium. In particular, the project will involve recovering the intrinsic X-ray spectrum from a specific model grid, in a sample of galaxies with direct X-ray observations for calibration and validation. This project will be led by a postdoctoral researcher at AIM, who will also use far-UV observations to constrain the amount of gas towards the X-ray source that affects the soft X-ray spectrum and introduces degeneracies in the modeling of X-ray observations.

Activités

- Main project: Building a sample of galaxies observed by Chandra, XMM-Newton, and Swift (in collaboration with the University of Geneva), creating XSPEC and Cloudy model grids (in collaboration with AIM researchers), and developing a Bayesian inference code (in collaboration with AIM researchers).
- Secondary project: Calculating constraints provided by far-UV absorption spectra (HST, FUSE; in collaboration with AIM researchers).
- Participation to collaboration meetings
- Collaborative visits in Paris and Geneva
- Writing publications.

Compétences

- Required experience with X-ray data (Chandra, XMM-Newton and/or Swift).
- Knowledge of the interstellar medium is not required but would be an asset (training possible in the first year).
- Experience with Bayesian calculations is not required but would be an asset (training possible in the first year).
- Proficiency in English at a level sufficient for scientific publications / oral presentations.

Contexte de travail

The work will take place at AIM, which is the CNRS joint research unit associated with the Astrophysics Department of CEA, Saclay, located 30 km (40 minutes) from the center of Paris. Including all personnel, AIM comprises 200 people and offers a dynamic environment addressing various fields of astrophysics, from cosmology to exoplanetary systems.