Search Publications
A high-resolution view of the filament of gas between Abell 399 and Abell 401 from the Atacama Cosmology Telescope and MUSTANG-2
Sarazin, Craig L.; Hilton, Matt; Sifón, Cristóbal +43 more
We report a significant detection of the hot intergalactic medium in the filamentary bridge connecting the galaxy clusters Abell 399 and Abell 401. This result is enabled by a low-noise, high-resolution map of the thermal Sunyaev-Zeldovich signal from the Atacama Cosmology Telescope (ACT) and Planck satellite. The ACT data provide the 1.65 arcmin …
Impact of ionization and electron density gradients in X-ray reflection spectroscopy measurements
Tripathi, Ashutosh; Abdikamalov, Askar B.; Bambi, Cosimo +1 more
The models currently used for the analysis of the reflection spectra of black holes usually assume a disc with constant ionization and electron density. However, there is some debate on the impact of these assumptions on the estimate of the properties of the sources, in particular when the fits suggest very steep emissivity profiles in the inner p…
A detailed study of the bridge of excess X-ray emission between the galaxy clusters Abell 2029 and Abell 2033
Walker, S. A.; Mirakhor, M. S.; Runge, J.
We examine Suzaku, XMM-Newton, and Chandra observations of the Abell 2029/2033 system to investigate the nature of a bridge of X-ray emission joining the two galaxy clusters. By modelling the contributions from the outskirts of the two clusters, and excluding the emission from the southern infalling group and the background group LOS9, we find a s…
Broad-band spectral analysis of Mrk 926 using multi-epoch X-ray observations
Buisson, D. J. K.; Russell, T. D.; Lohfink, A. M. +3 more
The X-ray spectra of some active galactic nuclei (AGNs) show a soft X-ray excess, emission in excess to the extrapolated primary X-ray continuum below 2 keV. Recent studies have shown that this soft excess can be described well as originating from either a relativistic ionized reflection, the extreme blurring of the reprocessed emission from the i…
Discovery of non-equilibrium ionization plasma associated with the North Polar Spur and Loop I
Kataoka, Jun; Sofue, Yoshiaki; Yamamoto, Marino
We investigated the detailed plasma condition of the North Polar Spur (NPS)/Loop I using archival Suzaku data. In previous research, collisional ionization equilibrium (CIE) have been assumed for X-ray plasma state, but we also assume non-equilibrium ionization (NEI) to check the plasma condition in more detail. We found that most of the plasma in…
Eclipse Timings of the LMXB XTE J1710-281 : discovery of a third orbital period glitch
Paul, Biswajit; Jain, Chetana; Sharma, Rahul
We present an updated measurement of orbital period evolution of LMXB XTE J1710-281 by using eclipse timing technique. Using data obtained with XMM-Newton, Suzaku, RXTE, Chandra, and AstroSat observatories, we report 21 new measurements of X-ray mid-eclipse times. We have discovered a third orbital period glitch in XTE J1710-281 with an F-test fal…
Simple interpretation of the seemingly complicated X-ray spectral variation of NGC 5548
Sugawara, Yasuharu; Ebisawa, Ken; Mizumoto, Misaki +1 more
NGC 5548 is a very well-studied Seyfert 1 galaxy in broad wavelengths. Previous multiwavelength observation campaigns have indicated that its multiple absorbers are highly variable and complex. A previous study applied a two-zone partial covering model with different covering fractions to explain the complex X-ray spectral variation and reported a…
Broad-band spectral analysis of LMXB 2S 0921-63 with Suzaku
Jain, Chetana; Dutta, Anjan; Sharma, Prince
We present the broad-band spectral analysis of the low-mass X-ray binary 2S 0921-63 by using the Suzaku archival data covering the orbital phase between 0.31 and 1.16 during four close observations. It is the first time that a broad-band spectral analysis of 2S 0921-63 has been done up to 25 keV. The 0.5-10 keV XIS count rate varied between ~1 and…
A Suzaku sample of unabsorbed narrow-line and broad-line Seyfert 1 galaxies - II. Iron emission and absorption
Gallo, L. C.; Waddell, S. G. H.
A sample of 22 narrow-line type 1 Seyfert (NLS1) and 47 broad-line type 1 Seyfert (BLS1) galaxies observed with Suzaku is used to examine the Fe K-band properties of each group. Three different models are used to examine the presence of: narrow neutral Fe K α line at $6.4{\rm \, keV}$ and ionized Fe XXV and Fe XXVI emission lines (model A); a broa…
Long-term X-ray spectral variation of the Wolf-Rayet binary WR 102-1 in the Galactic bulge: evidence for wind distortion in the binary
Sugawara, Yasuharu; Ebisawa, Ken; Nagatsuka, Tomoki
WR 102-1 was detected by Suzaku as a conspicuous point source in the 6.7 keV intensity map of the central region of the Milky Way. The source was suggested as a possible Wolf-Rayet binary based on its X-ray and infrared spectral characteristics. The iron line emission is expected to originate in the Wolf-Rayet star's dynamic stellar wind when coll…