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The origin of the cosmic X-ray background: bridging observations with theory


Since its discovery 40 years ago, the origin of the diffuse cosmic X-ray background radiation, that fills every direction on the Sky, remains a mystery.

Despite significant progress in the field, recent surveys using the largest X-ray telescopes currently available, suggest large discrepancies between observations and model predictions with regards to the nature of the extragalactic populations responsible for the X-ray background.

This proposal has the ambitious but realistic goal to bridge this gap using a wide-area medium-deep X-ray survey supplemented by an unprecedented set of multi-wavelength observations. This unique data-set will be exploited to provide detailed information on the nature and the cosmological evolution of the different extragalactic populations that make up the X-ray background.

Such a detailed study is essential to understand the disagreement between recent observations and the models and to finally, after 40 years, resolve the origin of the diffuse X-ray radiation. The proposed re search will provide 1st class training to an experienced researcher on one of the most debated and high profile problems of observational cosmology.

This project will therefore, not only address a 40-year old issue but will also provide additional expertise, both observational and theoretical, to the applicant, boosting his career toward professional independence, maturity and competitiveness.

Call for proposal

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South Kensington Campus
United Kingdom