Search Publications
Planck intermediate results. V. Pressure profiles of galaxy clusters from the Sunyaev-Zeldovich effect
Böhringer, H.; Kneissl, R.; Dahle, H. +215 more
Taking advantage of the all-sky coverage and broadfrequency range of the Planck satellite, we study the Sunyaev-Zeldovich (SZ) and pressure profiles of 62 nearby massive clusters detected at high significance in the 14-month nominal survey. Careful reconstruction of the SZ signal indicates that most clusters are individually detected at least out …
Multiwavelength campaign on Mrk 509. XII. Broad band spectral analysis
Kaastra, J. S.; Kriss, G. A.; Bianchi, S. +12 more
The origin of the different spectral components present in the high-energy (UV to X-rays/gamma-rays) spectra of Seyfert galaxies is still being debated a lot. One of the major limitations, in this respect, is the lack of really simultaneous broad-band observations that allow us to disentangle the behavior of each component and to better constrain …
Planck intermediate results. X. Physics of the hot gas in the Coma cluster
Böhringer, H.; Kneissl, R.; Dahle, H. +207 more
We present an analysis of Planck satellite data on the Coma cluster observed via the Sunyaev-Zeldovich effect. Thanks to its great sensitivity, Planck is able, for the first time, to detect SZ emission up to r ≈ 3 × R500. We test previously proposed spherically symmetric models for the pressure distribution in clusters against the azimu…
X-ray follow-ups of XSS J12270-4859: a low-mass X-ray binary with gamma-ray Fermi-LAT association
Mukai, K.; Belloni, T.; de Martino, D. +10 more
Context. XSS J1227.0-4859 is a peculiar, hard X-ray source recently positionally associated to the Fermi-LAT source 1FGL J1227.9-4852/2FGL J1227.7-4853. Multi-wavelength observations have added information on this source, indicating a low-luminosity low-mass X-ray binary (LMXB), but its nature is still unclear.
Aims: To progress in our unders…
Constraining turbulence and conduction in the hot ICM through density perturbations
Churazov, E.; Gaspari, M.
Turbulence and conduction can dramatically affect the evolution of baryons in the universe; current constraints are however rare and uncertain. Using 3D high-resolution hydrodynamic simulations, tracking both electrons and ions, we study the effects of turbulence and conduction in the hot intracluster medium. We show how the power spectrum of the …
Interstellar medium composition through X-ray spectroscopy of low-mass X-ray binaries
Kaastra, J. S.; Costantini, E.; Pinto, C. +1 more
Context. The diffuse interstellar medium (ISM) is an integral part of the evolution of the entire Galaxy. Metals are produced by stars and their abundances are the direct testimony of the history of stellar evolution. However, the interstellar dust composition is not well known and the total abundances are yet to be accurately determined.
Aim…
MAXI J1659-152: the shortest orbital period black-hole transient in outburst
Díaz Trigo, M.; Parmar, A. N.; Belloni, T. +12 more
MAXI J1659-152 is a bright X-ray transient black-hole candidate binary system discovered in September 2010. We report here on MAXI, RXTE, Swift, and XMM-Newton observations during its 2010/2011 outburst. We find that during the first one and a half week of the outburst the X-ray light curves display drops in intensity at regular intervals, which w…
The Extended GMRT Radio Halo Survey. I. New upper limits on radio halos and mini-halos
Brunetti, G.; Kale, R.; Giacintucci, S. +5 more
Context. A fraction of galaxy clusters host diffuse radio sources called radio halos, radio relics and mini-halos. These are associated with the relativistic electrons and magnetic fields present on ~Mpc scales in the intra-cluster medium.
Aims: We aim to carry out a systematic radio survey of all luminous galaxy clusters selected from the RE…
Abell 2142 at large scales: An extreme case for sloshing?
Rossetti, M.; Molendi, S.; De Grandi, S. +4 more
We present results obtained with a new XMM-Newton observation of A2142, a textbook example of a cluster with multiple cold fronts, which has been studied in detail with Chandra but whose large scale properties are presented here for the first time. We report the discovery of a new cold front, the most distant one ever detected in a galaxy cluster,…
A comprehensive picture of baryons in groups and clusters of galaxies
Zhang, Y. -Y.; Martinet, N.; Durret, F. +3 more
Aims: Based on XMM-Newton, Chandra, and SDSS data, we investigate the baryon distribution in groups and clusters and its use as a cosmological constraint. For this, we considered a sample of 123 systems with temperatures kT500 = 1.0-9.0 keV, total masses in the mass range M500 = (~1013-4 × 1015)h