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We present a detailed spectral analysis of an X-Ray Imaging and Spectroscopy Mission (XRISM) observation of the prototypical Seyfert 1 galaxy NGC 5548. XRISM’s Resolve microcalorimeter reveals, for the first time, highly ionized outflows in this active galactic nucleus (AGN) through the detection of Fe XXV and Fe XXVI absorption lines in the Fe K…

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The Bidirectional Polarization Distribution Function (BPDF) is essential in quantitative remote sensing, particularly for understanding the anisotropy of land surface polarization properties. The widely-used BRDF-BPDF dataset claimed to not corrected for aerosol scattering, which lay a hidden problem for BPDF modeling. In our work, we conducted aerosol correction based on Chinese polarimetric data DPC-2/GF-5(02), and…

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The X-ray source in active galactic nuclei (AGNs) is commonly referred to as the corona by analogy to stellar coronae. The similarities between the two suggest that the heating mechanism of AGN coronae is magnetic reconnection—as in cool stars—but this has not yet been directly observed. This work presents the first observational evidence for a…

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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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We present a search for exomoons around the Jupiter-like exoplanet Kepler-167e using a NIRSpec JWST transit. Our 60 hr time series clearly reveals the enormous impact of long-term trends in NIRSpec data, specifically a gradual flux drift occurring over each of six 10 hr exposures. We weighed the evidence for exomoons by comparing a planet-only…

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Decomposing the contributions of active galactic nuclei (AGNs) from their host galaxies is essential for identifying AGN-dominated galaxies and accurately deriving key physical properties of both supermassive black holes (SMBHs) and their host galaxies, such as black hole accretion rates, stellar masses, and star formation rates. However, decomposing AGN contributions from multi-wavelength photometry remains challenging…

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