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[O IV]- and [Ne V]-weak Active Galactic Nuclei Hidden by Compton-thick Material in Late Mergers
Imanishi, Masatoshi; Wada, Keiichi; Tanimoto, Atsushi +10 more
We study "buried" active galactic nuclei (AGNs) almost fully covered by circumnuclear material in ultra/luminous infrared galaxies (U/LIRGs), which show weak ionized lines from narrow-line regions. Employing an indicator of a [O IV] 25.89 or [Ne V] 14.32 µm line to 12 µm AGN luminosity ratio, we find 17 buried AGN candidates that are […
Gas-dynamical Mass Measurements of the Supermassive Black Holes in the Early-type Galaxies NGC 4786 and NGC 5193 from ALMA and HST Observations
Ho, Luis C.; Barth, Aaron J.; Buote, David A. +10 more
We present molecular gas-dynamical mass measurements of the central black holes in the giant elliptical galaxies NGC 4786 and NGC 5193, based on CO (2‑1) observations from the Atacama Large Millimeter/submillimeter Array (ALMA) and Hubble Space Telescope near-infrared imaging. The central region in each galaxy contains a circumnuclear disk that ex…
The Outflowing [O II] Nebulae of Compact Starburst Galaxies at z ∼ 0.5
Moustakas, John; Coil, Alison L.; Rudnick, Gregory H. +11 more
High-velocity outflows are ubiquitous in compact, massive (M * ∼ 1011 M ⊙), z ∼ 0.5 galaxies with extreme star formation surface densities (ΣSFR ∼ 2000 M ⊙ yr‑1 kpc‑2). We have previously detected and characterized these outflows using Mg II absorption lines. To probe the…
An Edge-on Regular Disk Galaxy at z = 5.289
Yan, Haojing; Ling, Chenxiaoji; Sun, Bangzheng
While rotation-supported gas disks are known to exist as early as at z ≈ 7, it is still a general belief that stellar disks form late in the Universe. This picture is now being challenged by the observations from the James Webb Space Telescope (JWST), which have revealed a large number of disk-like galaxies that could be at z > 3, with some bei…
The Timescales of Star Cluster Emergence: The Case of NGC 4449
Smith, Linda J.; Calzetti, Daniela; Johnson, Kelsey E. +7 more
We survey the young star cluster population in the dwarf galaxy NGC 4449 with the goal of investigating how stellar feedback may depend on the clusters' properties. Using ultraviolet (UV)–optical–near-infrared photometry obtained with the Hubble Space Telescope, we have recovered 99 compact sources exhibiting emission in the Paβ hydrogen recombina…
Hemispheric Distribution of Halo Coronal Mass Ejection Source Locations
Mei, Ying; Wang, Feng; Deng, Hui +2 more
The hemispheric asymmetry of solar activity is one of the essential physical consequences of the interior dynamo process. However, the hemispheric distribution of halo coronal mass ejection (HCME) source locations has not been investigated in detail. Based on the HCME catalog identified from the Large Angle and Spectrometric Coronagraph Experiment…
Surface Flux Transport Modeling Using Physics-informed Neural Networks
Cheung, Mark C. M.; Athalathil, Jithu J.; Vaidya, Bhargav +2 more
Studying the magnetic field properties on the solar surface is crucial for understanding the solar and heliospheric activities, which in turn shape space weather in the solar system. Surface flux transport (SFT) modeling helps us to simulate and analyze the transport and evolution of magnetic flux on the solar surface, providing valuable insights …
Deep Chandra Observations of A2495: A Possible Sloshing-regulated Feedback Cycle in a Triple-offset Galaxy Cluster
Gastaldello, F.; Gaspari, M.; O'Sullivan, E. +6 more
We present the analysis of new, deep Chandra observations (130 ks) of the galaxy cluster A2495. This object is known for the presence of a triple offset between the peaks of the intracluster medium (ICM), the brightest cluster galaxy (BCG), and the warm gas glowing in Hα line. The new Chandra data confirm that the X-ray emission peak is located at…
Connecting Solar Wind Velocity Spikes Measured by Solar Orbiter and Coronal Brightenings Observed by SDO
Sorriso-Valvo, Luca; Verscharen, Daniel; D'Amicis, Raffaella +28 more
The Parker Solar Probe's discovery that magnetic switchbacks and velocity spikes in the young solar wind are abundant has prompted intensive research into their origin(s) and formation mechanism(s) in the solar atmosphere. Recent studies, based on in situ measurements and numerical simulations, argue that velocity spikes are produced through inter…
An HST Study of the Substellar Population of NGC 2024
Da Rio, Nicola; Gennaro, Mario; Sabbi, Elena +6 more
We performed an HST/WFC3-IR imaging survey of the young stellar cluster NGC 2024 in three filters probing the 1.4 µm H2O absorption feature, characteristic of the population of low-mass and substellar-mass objects down to a few Jupiter masses. We detect 812 point sources, 550 of them in all three filters with signal-to-noise ratio…