XRISM Spectroscopy of Variable Accretion-driven Disk Winds in NGC 4151: When, Where, and How Fast Outflows are Launched

01/10/2026 - Low-Energy

X-ray observations probe the inner accretion flow within active galactic nuclei, revealing the highest gas column densities and fastest winds. The most diverse winds yet revealed with the Resolve calorimeter spectrometer aboard XRISM are found in NGC 4151, a nearby Seyfert 1 active galactic nucleus (AGN) that may qualify as a changing-look source (CLAGN). Herein,…

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Advancing the detection of low surface brightness galaxies: I. ATTILA: multi-tAsking deTecTIon tool for Lsb gAlaxies

01/10/2026 - Low-Energy

Context. Ultra-diffuse galaxies (UDGs) lie at the extreme end of the size–luminosity distribution of low-surface-brightness (LSB) galaxies. Their detection and characterization require deep imaging and reliable source detection techniques that can handle low signal-to-noise ratios and severe source blending. Aims. We aim at improving the detection and characterization of LSB galaxies and UDG candidates in…

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Can the long-term impact of stellar M-dwarf flares alter the spectral features of a giant gaseous exoplanet?

01/10/2026 - Exoplanets

In this work, we model the long-term impact of recurrent stellar flares on the atmospheres of metal-rich gaseous exoplanets. Using synthetic flare spectra from a fiducial flare model integrated with a photochemical kinetics code, we track the changes in atmospheric composition with time. We further analyze the spectral variability by feeding these abundance profiles into…

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