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NuSTAR Observations of 52 Compton-thick Active Galactic Nuclei Selected by the Swift/Burst Alert Telescope All-sky Hard X-Ray Survey
Tanimoto, Atsushi; Ueda, Yoshihiro; Ricci, Claudio +2 more
We present systematic broadband X-ray spectral analysis of 52 Compton-thick ( $24\leqslant \mathrm{log}{N}_{{\rm{H}}}^{\mathrm{LOS}}/{\mathrm{cm}}^{-2}$ ) active galactic nucleus (CTAGN) candidates selected by the Swift/Burst Alert Telescope all-sky hard X-ray survey observed with Chandra, X-ray Multi-Mirror Mission-Newton (XMM-Newton), Swift/X-Ra…
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 …
New Constraints on the Spin of the Black Hole Cygnus X-1 and the Physical Properties of its Accretion Disk Corona
Krawczynski, H.; Beheshtipour, B.
We present a new analysis of NuSTAR and Suzaku observations of the black hole Cygnus X-1 in the intermediate state. The analysis is performed using kerrC, a new model for analyzing spectral and spectropolarimetric X-ray observations of black holes. kerrC builds on a large library of simulated black holes in X-ray binaries. The model accounts for t…
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…
Spectral break of energetic pulsar wind nebulae detected with wideband X-ray observations
Terada, Yukikatsu; Uchida, Hiroyuki; Bamba, Aya +4 more
Pulsar wind nebulae (PWNe) are one of the most energetic galactic sources with bright emissions from radio waves to very high-energy gamma-rays. We perform wideband X-ray spectroscopy of four energetic PWNe, N 157 B, PSR J1813-1749, PSR J1400-6325, and G21.5-0.9, with the Suzaku, Chandra, NuSTAR, and Hitomi observatories. A significant spectral br…
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…
The soft X-ray background with Suzaku. I. Milky Way halo
Sato, Kosuke; Yamasaki, Noriko Y.; Matsushita, Kyoko +4 more
We present measurements of the soft X-ray background emission for 130 Suzaku observations at 75° < l < 285° and |b| > 15° obtained from 2005 to 2015, covering nearly one solar cycle. In addition to the standard soft X-ray background model consisting of the local hot bubble and the Milky Way Halo (MWH), we include a hot collisional-ionizat…
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…