845 citations · 1.5k across the 36 of their papers we have counts for
25 papers · 1 filter
XRISM High-Resolution X-ray Spectroscopy of Cygnus X-1 -- highly ionized Iron absorption structures
Shinya Yamada, Natalie Hell, Elisa Costantini +18
We present the first high-resolution X-ray spectral analysis of Cygnus X-1 using XRISM. The observation was carried out from April 7 to 10, 2024, covering the orbital phase range 0…
High Spectral Resolution X-ray Observations of the Evolved Supermassive Stellar Binary System Carinae - Iron K Band Profile Revealed with XRISM
XRISM Collaboration, Marc Audard, Hisamitsu Awaki +138
The supermassive binary system, Carinae, is experiencing enormous wind-driven mass loss at a rate unparalleled in the rest of the Galaxy. Their wind-wind collision (WWC) contin…
Energy shift of Fe-K fluorescence lines due to low ionization demonstrated with XRISM in Centaurus X-3
Yutaro Nagai, Teruaki Enoto, Masahiro Tsujimoto +13
The Fe K fluorescence line at 6.4 keV is a powerful probe of cold matter surrounding X-ray sources and has been widely used in various astrophysical contexts. The X-ray microcal…
Indication of the Less-ionized Clumpy Ultra-Fast Outflows in Seyfert Galaxies
Takuya Midooka, Misaki Mizumoto, Ken Ebisawa
We present a systematic investigation of X-ray spectral variability of Seyfert 1 galaxies using a ``spectral-ratio model fitting'' technique, which we developed to estimate contrib…
XRISM finds the Changing-Look AGN NGC 1365 in an extended low state: A dense, highly ionized outflow obscures the central source
Fatima Zaidouni, Erin Kara, Peter Kosec +21
We present the first XRISM/Resolve observations of the active galactic nucleus, NGC 1365, obtained in 2024 February and July. NGC 1365 is known for rapid transitions between Compto…
Chlorine and Potassium Enrichment in the Cassiopeia A Supernova Remnant
XRISM collaboration
The elements in the universe are synthesized primarily in stars and supernovae, where nuclear fusion favors the production of even-Z elements. In contrast, odd-Z elements are less…
XRISM constraints on unidentified X-ray emission lines, including the 3.5 keV line, in the stacked spectrum of ten galaxy clusters
XRISM Collaboration, Marc Audard, Hisamitsu Awaki +150
We stack 3.75 Megaseconds of early XRISM Resolve observations of ten galaxy clusters to search for unidentified spectral lines in the 2.5-15 keV band (rest frame), including t…
Stratified wind from a super-Eddington X-ray binary is slower than expected
XRISM collaboration, Marc Audard, Hisamitsu Awaki +132
Accretion discs in strong gravity ubiquitously produce winds, seen as blueshifted absorption lines in the X-ray band of both stellar mass X-ray binaries (black holes and neutron st…
XRISM/Resolve View of Abell 2319: Turbulence, Sloshing, and ICM Dynamics
XRISM Collaboration, Marc Audard, Hisamitsu Awaki +132
We present results from XRISM/Resolve observations of the core of the galaxy cluster Abell 2319, focusing on its kinematic properties. The intracluster medium (ICM) exhibits temper…
Disentangling Multiple Gas Kinematic Drivers in the Perseus Galaxy Cluster
XRISM Collaboration, Marc Audard, Hisamitsu Awaki +143
Galaxy clusters, the Universe's largest halo structures, are filled with 10-100 million degree X-ray-emitting gas. Their evolution is shaped by energetic processes such as feedback…
Structured ionized winds shooting out from a quasar at relativistic speeds
XRISM collaboration
Evidence indicates that supermassive black holes exist at the centers of most galaxies. Their mass correlates with the galactic bulge mass, suggesting a co-evolution with their hos…
XRISM forecast for the Coma cluster: stormy, with a steep power spectrum
XRISM Collaboration, Marc Audard, Hisamitsu Awaki +142
The XRISM Resolve microcalorimeter array measured the velocities of hot intracluster gas at two positions in the Coma galaxy cluster: 3'x3' squares at the center and at 6' (170 kpc…
The bulk motion of gas in the core of the Centaurus galaxy cluster
XRISM collaboration
Galaxy clusters, the largest gravitationally bound structures in the Universe, contain vast amounts of dark matter, galaxies, and hot ionised gas known as the intracluster medium (…
Overionized plasma in the supernova remnant Sagittarius A East anchored by XRISM observations
XRISM Collaboration
Sagittarius A East is a supernova remnant with a unique surrounding environment, as it is located in the immediate vicinity of the supermassive black hole at the Galactic center, S…
The XRISM/Resolve view of the Fe K region of Cyg X-3
XRISM Collaboration
The X-ray binary system Cygnus X-3 (4U 2030+40, V1521 Cyg) is luminous but enigmatic owing to the high intervening absorption. High-resolution X-ray spectroscopy uniquely probes th…
Detection of the orbital modulation of Fe K fluorescence emission in Centaurus X-3 using the high-resolution spectrometer Resolve onboard XRISM
Yuto Mochizuki, Masahiro Tsujimoto, Richard L. Kelley +9
The Fe K fluorescence line emission in X-ray spectra is a powerful diagnostic tool for various astrophysical objects to reveal the distribution of cold matter around photo-ioniz…
Spectral Modeling of the Supersoft X-ray Source CAL87 based on Radiative Transfer Codes
Masahiro Tsujimoto, Misaki Mizumoto, Ken Ebisawa +2
Super Soft X-ray Sources (SSS) are white dwarf (WD) binaries that radiate almost entirely below 1~keV. Their X-ray spectra are often complex when viewed with the X-ray gratin…
X-ray spectral variations of Circinus X-1 observed with NICER throughout an entire orbital cycle
Mayu Tominaga, Masahiro Tsujimoto, Ken Ebisawa +2
Circinus X-1 (Cir X-1) is a neutron star binary with an elliptical orbit of 16.6~days. The source is unique for its extreme youth, providing a key to understanding early binary evo…
The CALorimetric Electron Telescope (CALET) on the International Space Station: Results from the First Two Years On Orbit
Y. Asaoka, O. Adriani, Y. Akaike +90
The CALorimetric Electron Telescope (CALET) is a high-energy astroparticle physics space experiment installed on the International Space Station (ISS), developed and operated by Ja…
Temperature Structure in the Perseus Cluster Core Observed with Hitomi
Hitomi Collaboration, Felix Aharonian, Hiroki Akamatsu +192
The present paper investigates the temperature structure of the X-ray emitting plasma in the core of the Perseus cluster using the 1.8--20.0 keV data obtained with the Soft X-ray S…
Hitomi constraints on the 3.5 keV line in the Perseus galaxy cluster
Hitomi Collaboration, Felix A. Aharonian, Hiroki Akamatsu +215
High-resolution X-ray spectroscopy with Hitomi was expected to resolve the origin of the faint unidentified E=3.5 keV emission line reported in several low-resolution studies of va…
ASTRO-H White Paper - AGN Winds
J. S. Kaastra, Y. Terashima, T. Kallman +23
In this white paper we describe the prospects for ASTRO-H for the study of outflows from active galactic nuclei. The most important breakthroughs in this field are expected to aris…
Accretion disk and ionized absorber of the 9.7-hour dipping black hole binary MAXI J1305-704
Megumi Shidatsu, Yoshihiro Ueda, Satoshi Nakahira +14
We report the results from X-ray studies of the newly discovered black hole candidate MAXI J1305-704 based on Suzaku and Swift observations in the low/hard and high/soft states, re…
On the light-bending model of X-ray variability of MCG-6-30-15
P. T. Zycki, K. Ebisawa, A. Niedzwiecki +1
We apply the light bending model of X-ray variability to Suzaku data of the Seyfert 1 galaxy MCG-6-30-15. We analyze the energy dependence of the root mean square (rms) variability…