X-ray Astronomy

Modern astronomy has turned into a discipline which combines theory, numerical modelling and observations at all wavelengths. X-ray observations, which have developed over the last 45 years, are especially efficient in mapping highly energetic phenomena like matter orbiting and ultimately falling onto black holes and other compact objects, hot gas in galaxies and clusters and active coronae. In addition hard X-rays (photons with energies above a few keV) manage to penetrate through the obscuring environment that prevents us from observing some of these phenomena at other wavelengths. Although it is clear that the higher the photon the better for these purposes, the scarcity of photons at higher energies and the difficulty in collecting them both in space (MeV/GeV) or from the ground (TeV), in practice render X-ray Astronomy as the most efficient and sensitive way to map high-energy phenomena in the Universe in the foreseeable future.

Our group is particularly interested in studying the growing massive black holes that populate the centres of galaxies and that show up, when this accretion is significant, as Active Galactic Nuclei (AGN). This is accomplished via detailed studies of relatively close objects and also via statistical studies of distant objects that we discover via a variety of X-ray surveys. Our research, which is triggered often by X-ray observations, is complemented by observations in optical ground-based telescopes and with archival data from a variety of observatories.

Our group has built substantial expertise in developing data analysis software, pipelines and archival tools for XMM-Newton (via the Survey Science Centre) as well as for an European-Japanese calorimeter prototype (EURECA) which is currently under development. We have also had a leading role in triggering an R&D activity in other CSIC Institutes towards the development of new sensors capable of delivering high spectroscopic resolution X-ray bolometers. These activities are an integral part of our current and future goals.

The main scientific goal of our R&D activities is to make significant progress towards the understanding of cosmic history of the growth of massive black holes and its relation to the star formation history in galaxies. The two processes (black hole growth and star formation) are key ingredients in the formation of galaxies and they are probably closely linked through feedback processes. ESA’s observatory XMM-Newton will be operational at least until 2014 and it is not unfeasible that its life could be further extended. XMM-Newton is leaving a major legacy, the 2XMM X-ray source catalogue, that we helped to create through the Survey Science Centre. With dedicated X-ray observations (complemented with observations at other wavebands) and the exploitation of the archive and source catalogue, we expect to continue in making significant progress towards that overarching goal.

But beyond the current X-ray observatories (ESA’s XMM-Newton, NASA’s Chandra and JAXA’s Suzaku), a new frontier of more powerful facilities appears in the horizon: several mission concepts that have been proposed to ESA's Cosmic Vision programme and ultimately the International X-ray Observatory (IXO), a joint collaboration between ESA, JAXA and NASA, with a launch date > 2020. Our group has been for over a decade heavily involved in several aspects of IXO (formerly XEUS in Europe). We plan to continue this deep involvement in IXO, especially in the mission definition front.