Search Publications
Athena: ESA's X-ray observatory for the late 2020s
Piro, L.; Nandra, K.; Barcons, X. +8 more
Observations of the X-ray sky after the next decade will most likely be dominated by Athena (Advanced Telescope for High ENergy Astrophysics), the second large mission of ESA's Cosmic Vision 2015-2035 programme. Athena has been conceived to address the "Hot and Energetic Universe" science theme, which focuses on the assembly and evolution of hot b…
The XMM cluster outskirts project (X‑ COP )
Pointecouteau, E.; Paltani, S.; Molendi, S. +3 more
Galaxy clusters are thought to grow hierarchically through the continuous merging and accretion of smaller structures across cosmic time. In the local Universe, these phenomena are still active in the outer regions of massive clusters ($R>R_{500}$), where the matter distribution is expected to become clumpy and asymmetric because of the presenc…
A decade of warm hot intergalactic medium searches: Where do we stand and where do we go?
Elvis, M.; Nicastro, F.; Krongold, Y. +1 more
In this article, we first review the past decade of efforts in detecting the missing baryons in the warm hot intergalactic medium and summarize the current state of the art by updating the baryon census and physical state of the detected baryons in the local Universe. We then describe observational strategies that should enable a significant step …
Cosmology with AGN: can we use quasars as standard candles?
Lusso, E.; Risaliti, G.
The nonlinear relation between X-ray and UV luminosity in quasars can be used to estimate their distance. Recently, we have shown that, despite the large dispersion of the relation, a Hubble diagram made of large samples of quasars can provide unique constraints on cosmology at high redshift. Furthermore, the dispersion of the relation is heavily …
Follow-up of isolated neutron star candidates from the eROSITA survey
Motch, C.; Pires, A. M.; Schwope, A. D.
Peculiar groups of X-ray emitting isolated neutron stars, which include magnetars, the "magnificent seven", and central compact objects in supernova remnants, escape detection in standard pulsar surveys. Yet, they constitute a key element in understanding the neutron star evolution and phenomenology. Their use in population studies in the galactic…
Ultrafast outflows in ultraluminous X‑ray sources
Pinto, C.; Walton, D.; Fabian, A. +1 more
Ultraluminous X-ray sources (ULXs) are bright extragalactic sources with X-ray luminosities above 10^39 erg/s powered by accretion onto compact objects. According to the first studies performed with XMM-Newton ULXs seemed to be excellent candidates to host intermediate-mass black holes (10^2-4 solar masses). However, in the last years the interpre…
Tidal disruption of stars by super-massive black holes—XMM-Newton highlights and the next decade
Komossa, S.
This article provides a summary of XMM-Newton highlights on stellar tidal disruption events. First found with ROSAT, ongoing and upcoming sky surveys will detect these events in the thousands. In X-rays, tidal disruption events (TDEs) provide us with powerful new probes of accretion physics under extreme conditions and on short timescales and of r…
High-resolution X-ray spectroscopy: The coming-of-age
Kaastra, J. S.
Since the launch of Chandra and XMM-Newton, high-resolution X-ray spectra of cosmic sources of all kinds have become available. These spectra have resulted in major scientific breakthroughs. However, due to the techniques used, in general high-quality spectra can only be obtained for the brightest few sources of each class. Moreover, except for th…
The XXL survey: First results and future
Smith, G. P.; Okabe, N.; Chiappetti, L. +108 more
The XXL survey currently covers two 25 deg2 patches with XMM observations of ∼10 ks. We summarize the scientific results associated with the first release of the XXL dataset, which occurred in mid-2016. We review several arguments for increasing the survey depth to 40 ks during the next decade of XMM operations. X-ray (z < 2) cluster…
High-redshift active galactic nuclei and the next decade of Chandra and XMM-Newton
Brandt, W. N.; Vito, F.
We briefly review how X-ray observations of high-redshift active galactic nuclei (AGNs) at z = 4-7 have played a critical role in understanding their basic demographics as well as their physical processes; for example, absorption by nuclear material and winds, accretion rates, and jet emission. We point out some key remaining areas of uncertainty,…