Search Publications
Witnessing the growth of the nearest galaxy cluster: thermodynamics of the Virgo Cluster outskirts
Simionescu, A.; Allen, S. W.; Werner, N. +2 more
We present results from Suzaku Key Project observations of the Virgo Cluster, the nearest galaxy cluster to us, mapping its X-ray properties along four long 'arms' extending beyond the virial radius. The entropy profiles along all four azimuths increase with radius, then level out beyond ∼0.5r200, while the average pressure at large rad…
A uniform metallicity in the outskirts of massive, nearby galaxy clusters
Simionescu, A.; Allen, S. W.; Werner, N. +2 more
Suzaku measurements of a homogeneous metal distribution of Z ∼ 0.3 Solar in the outskirts of the nearby Perseus cluster suggest that chemical elements were deposited and mixed into the intergalactic medium before clusters formed, likely over 10 billion years ago. A key prediction of this early enrichment scenario is that the intracluster medium in…
The high-Eddington NLS1 Ark 564 has the coolest corona
Fabian, A. C.; Reynolds, C. S.; Lohfink, A. +4 more
Ark 564 is an archetypal narrow-line Seyfert 1 that has been well observed in soft X-rays from 0.3-10 keV, revealing a steep spectrum, strong soft excess, iron K emission line and dramatic variability on the order of hours. Because of its very steep spectrum, observations of the source above 10 keV have been sparse. We report here on the first NuS…
Deep LOFAR observations of the merging galaxy cluster CIZA J2242.8+5301
Brunetti, G.; White, G. J.; Shimwell, T. W. +20 more
Previous studies have shown that CIZA J2242.8+5301 (the 'Sausage' cluster, z = 0.192) is a massive merging galaxy cluster that hosts a radio halo and multiple relics. In this paper, we present deep, high-fidelity, low-frequency images made with the LOw-Frequency Array (LOFAR) between 115.5 and 179 MHz. These images, with a noise of 140 µJy b…
Analysis of NuSTAR and Suzaku observations of Cyg X-1 in the hard state: evidence for a truncated disc geometry
Parker, Michael; Zdziarski, Andrzej A.; Basak, Rupal +1 more
The geometry of the accretion flow in black hole X-ray binaries in the hard state, in particular the position of the disc inner edge, has been a subject of intense debate in recent years. We address this issue by performing a spectral study of simultaneous observations of Cyg X-1 in the hard state by NuSTAR and Suzaku. The same data were analysed …
Suzaku spectroscopy of the neutron star transient 4U 1608-52 during its outburst decay.
Armas Padilla, M.; Muñoz-Darias, T.; Hori, T. +2 more
We test the proposed three-component spectral model for neutron star low-mass X-ray binaries using broad-band X-ray data. We have analysed four X-ray spectra (0.8-30 keV) obtained with Suzaku during the 2010 outburst of 4U 1608-52, which have allowed us to perform a comprehensive spectral study covering all the classical spectral states. We use a …
Study of orbital and superorbital variability of LSI +61° 303 with X-ray data
Tsygankov, S.; Takahashi, H.; Babyk, Iu. +4 more
LSI +61° 303 is one of the few X-ray binaries with a Be star companion from which radio, X-rays and high-energy gamma-ray (GeV and TeV) emission have been observed. The nature of the high-energy activity of the system is not yet fully understood, but it is widely believed that it is generated due to the interaction of the relativistic electrons le…
X-ray flaring in PDS 456 observed in a high-flux state
Turner, T. J.; Reeves, J. N.; Braito, V. +3 more
We present an analysis of a 190 ks (net exposure) Suzaku observation, carried out in 2007, of the nearby (z = 0.184) luminous (Lbol ∼ 1047 erg s-1) quasar PDS 456. In this observation, the intrinsically steep bare continuum is revealed compared to subsequent observations, carried out in 2011 and 2013, where the sou…
Understanding the nature of the intriguing source X Persei: a deep look with a Suzaku observation
Maitra, Chandreyee; Paul, Biswajit; Pradhan, Pragati +1 more
We present detailed broad-band timing and spectral analysis of the persistent, low luminosity and slowly spinning pulsar X Persei using a deep Suzaku observation of the source. The spectrum is unusually hard with a cyclotron resonance scattering feature (CRSF), the presence of which has been debated. By comparing the spectral models relevant for a…
X-ray lags in PDS 456 revealed by Suzaku observations
Fabian, A. C.; Reynolds, C. S.; Cackett, E. M. +5 more
X-ray reverberation lags from the vicinity of supermassive black holes have been detected in almost 30 active galactic nuclei (AGNs). The soft lag, which is the time delay between the hard and soft X-ray light curves, is usually interpreted as the time difference between the direct and reflected emission, but is alternatively suggested to arise fr…