activity
20242026
most citedChlorine and Potassium Enrichment in the Cassiopeia A Supernova Remnant

5 citations · 10 across the 17 of their papers we have counts for

collaborators

19 papers

astro-ph.HE2026

Remnant-wide mapping of heterogeneous presupernova burning histories in the O-rich ejecta of Cassiopeia A

Yui Kuboike, Toshiki Sato, Kai Matsunaga

Late-stage shell interactions, including shell mergers, can mix material across adjacent burning shells and imprint chemically inhomogeneous structures in the hydrostatic O-rich la…

astro-ph.HE2026

Testing a Pre-Supernova Contribution to Ti in Cassiopeia A

Toshiki Sato, Joshua Issa, Falk Herwig +4

The radioactive isotope Ti in Cassiopeia A has been used as a tracer of the innermost ejecta and explosion asymmetries in core-collapse supernova explosions. However, recent…

astro-ph.HE2026

Distinct Velocity Components in the Absorption Lines of the Neutron Star X-ray Binary AX J1745.6-2901

Kai Matsunaga, Maxime Parra, Yutaro Nagai +10

Accretion disks in X-ray binaries regulate mass transfer onto compact objects and drive radiative and kinetic feedback to their surroundings. Here we report X-ray spectroscopy of t…

astro-ph.HE2026

Chandra X-Ray Imaging and Spatially Resolved Spectroscopy of SN 1987A: Energy-Dependent Morphology of the Equatorial Ring

Yusuke Sakai, Shinya Yamada, Koji Mori +8

We present a systematic imaging and spatially resolved spectral study of SN 1987A using Chandra observations obtained between 1999 and 2025. By combining multiepoch ACIS and HETG d…

astro-ph.HE2026

XRISM spectroscopy of a crowded Galactic center region -- I. Disentangling the sources in the field of view

Maxime Parra, Kai Matsunaga, Shifra Mandel +16

The Galactic center is a complex and crowded region hosting the supermassive black hole Sgr A*, numerous accreting compact objects, and diffuse X-ray emission. This paper presents…

astro-ph.HE2026

XRISM spectroscopy of a crowded Galactic center region -- II. Narrow emission lines in the Black Hole candidate MAXI J1744-294/Swift J174540.2-290037

Maxime Parra, Shifra Mandel, Kai Matsunaga +13

Narrow, highly ionized X-ray emission lines in black hole low-mass X-ray binaries (BH-LMXBs) are rare and have been observed in only a few sources, during unusual, heavily obscured…

astro-ph.HE2026

XRISM spectroscopy of a crowded Galactic center region -- III. S, Ar and Ca ISM Absorption Features in the spectrum of MAXI J1744-294

Efrain Gatuzz, Maxime Parra, Muhammet F. Hasoglu +7

We present a comprehensive study of X-ray absorption by sulfur (S), argon (Ar), and calcium (Ca) in the interstellar medium (ISM) along the line of sight to the low-mass X-ray bina…

astro-ph.HE2026

The Supernova Remnant G284.31.8 and Its Relation to the Gamma-ray Binary 1FGL J1018.65856

Natsuki Terano, Takaaki Tanaka, Hiromasa Suzuki +6

G284.31.8 is a supernova remnant with a radio shell and thermal X-ray emission. Located near its center is the gamma-ray binary 1FGL J1018.65856, although the physical associ…

astro-ph.HE2026

Asymmetric distribution of Fe-peak elements in Cassiopeia A revealed by XRISM

Toshiki Sato, Shin-ichiro Fujimoto, Koji Mori +20

The elemental abundances of the Fe-peak elements (such as Cr, Mn, Fe and Ni) and Ti are important for understanding the environment of explosive nuclear burning for the core-collap…

astro-ph.HE2025★ 5 cited

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…

astro-ph.HE2025

The Origin of the Mg-rich Supernova Remnant J0550-6823 and the Frequency of Similar Events in the Large Magellanic Cloud

Yui Kuboike, Toshiki Sato, Hiromasa Suzuki +4

Shell burning and internal mixing in massive stars play an important role in setting the initial conditions for core-collapse supernova explosions. In the late stages of stellar ev…

astro-ph.HE2025

A multiwavelength study of the Galactic center black hole candidate MAXI J1744-294

Shifra Mandel, Kaya Mori, Paul A. Draghis +37

For the first time in nearly a decade, a bright transient was detected in the central parsec (pc) of the Galaxy. MAXI J1744-294, or -- as it was known in its previous life -- Swift…

astro-ph.HE2025★ 3 cited

XRISM Observations of Cassiopeia A: Overview, Atomic Data, and Spectral Models

Paul Plucinsky, Manan Agarwal, Liyi Gu +15

Cassiopeia A (Cas A) is the youngest known core-collapse supernova remnant (SNR) in the Galaxy and is perhaps the best-studied SNR in X-rays. Cas A has a line-rich spectrum dominat…

astro-ph.HE2025

Inhomogeneous stellar mixing in the final hours before the Cassiopeia A supernova

Toshiki Sato, Kai Matsunaga, Hiroyuki Uchida +10

Understanding stars and their evolution is a key goal of astronomical research and has long been a focus of human interest. In recent years, theorists have paid much attention to t…

astro-ph.HE2025

Mapping Cassiopeia A's silicon/sulfur Doppler velocities with XRISM-Resolve

Jacco Vink, Manan Agarwal, Aya Bamba +22

Young supernova remnants (SNRs) provide crucial insights into explosive nucleosynthesis products and their velocity distribution soon after the explosion. However, these velocities…

astro-ph.HE2025

Measuring the asymmetric expansion of the Fe ejecta of Cassiopeia A with XRISM/Resolve

Aya Bamba, Manan Agarwal, Jacco Vink +24

The expansion structure of supernova remnants (SNRs) is important for understanding not only how heavy elements are distributed into space, but also how supernovae explode. The eje…

astro-ph.HE2024

Evidence for Type Ib/c origin of the supernova remnant G292.0+1.8

Takuto Narita, Hiroyuki Uchida, Jacco Vink +6

Circumstellar material (CSM) produced by mass loss from massive stars () through strong stellar winds or binary stripping provides rich information for underst…

astro-ph.HE2024

Progenitor Constraint Incorporating Shell Merger: The Case of Supernova Remnant G359.0-0.9

Kai Matsunaga, Hiroyuki Uchida, Rei Enokiya +5

It is generally hard to put robust constraints on progenitor masses of supernovae (SNe) and remnants (SNRs) observationally, while they offer tantalizing clues to understanding exp…

astro-ph.HE2024★ 2 cited

Destratification in the Progenitor Interior of the Mg-rich Supernova Remnant N49B

Toshiki Sato, Kai Matsunaga, Ryo Sawada +6

Simulations of pre-supernova evolution suggest that some intense shell burning can be so active that, in extreme cases, it can merge with the outer shell, changing the initial cond…