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Our publications

Silicon, Sulfur, and Iron in the Interstellar Medium: A High-resolution X-Ray Spectral Study of GX 340+0

01/05/2026 - High-Energy

High-resolution X-ray spectroscopy provides a powerful probe of the interstellar medium (ISM), giving direct access to the composition and physical state of dust grains and atomic species in dense environments. We present a study of the gas and dust along the line of sight to the bright low-mass X-ray binary GX 340+00, which samples higher-density…

Silicon-based vacuum window for millimeter- and submillimeter-wave astrophysics

01/05/2026 - Technology

We designed, fabricated, and characterized the properties of a silicon-based vacuum window suitable for millimeter-wave astrophysical applications. The window, which has a diameter of 124 mm, an optically usable diameter of 68 mm, and a thickness of about 4 mm, gives an average transmittance and reflectance of 99.6±3.5% and 1.3±1.4%, respectively, a fractional bandwidth of…

Reassessing planetary composition: Evidence of rock-dominated envelopes in Uranus and Neptune

01/05/2026 - Exoplanets

Although Uranus and Neptune are commonly classified as ice giants, their exact compositions remain poorly constrained. Recent studies of outer Solar System bodies challenge the traditional view that these planets are primarily ice-dominated, suggesting that refractory material plays a more significant role. Determining the proportions of ice and rock within Uranus and Neptune is essential…

The role of inner disk edges in shaping ultra-short-period planet systems around late M dwarfs

01/05/2026 - Exoplanets

Context. Close-in rocky planets are the most common type of exoplanets around late M dwarfs, ranging from more temperate worlds to highly irradiated lava planets with molten surfaces, and many theoretical studies have attempted to explain their formation. However, the origin of rocky planets with orbital periods shorter than one day, known as ultra-short-period (USP)…

The major merger─active galactic nucleus connection up to cosmic noon

01/04/2026 - Low-Energy

Galaxy major mergers are a potential mechanism for triggering active galactic nuclei (AGN) activity, but their role remains debated, particularly beyond the local Universe. We aim to shed light on the merger─AGN connection at z = 0.5─2, exploiting the multi-wavelength datasets and James Webb Space Telescope (JWST) observations in the COSMOS field. We construct a…

XRISM high-resolution X-ray spectroscopy of Cygnus X-1: Orbital and short-term variability of iron absorption

01/04/2026 - High-Energy

We present the first high-resolution spectroscopy of the black hole high-mass X-ray binary Cygnus X-1 with XRISM, including orbital-phase-resolved analyses and tentative evidence of short-term variability in the Fe K band on second timescales. Using data from the Performance Verification phase in 2024 April, we analyzed spectral variability across orbital phases with the Resolve microcalorimeter…

Publications