Results 31 to 40 of about 1,904 (106)
The Messy Nature of Fiber Spectra: Star–Quasar Pairs Masquerading as Dual Type 1 AGNs
The Astrophysical Journal, 2023 Theoretical studies predict that the most significant growth of supermassive black holes (SMBHs) occurs in late-stage mergers, coinciding with the manifestation of dual active galactic nuclei (AGNs), and both major and minor mergers are expected to be ...
Ryan W. Pfeifle +7 more
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, 2022 Introduction into AGN given at SSAASS with focus on radio features of ...
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The Astrophysical JournalWe present a high-resolution X-ray spectroscopic study of the narrow-line Seyfert 1 galaxy NGC 4051 using two XMM-Newton high-resolution Reflection Grating Spectrometer observations.
Roberto Serafinelli +8 more
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The Astrophysical JournalWe present a time-resolved X-ray spectral analysis of the warm absorbers in the Seyfert galaxy NGC 4051, which has an active galactic nucleus (AGN), using observations from the Neutron Star Interior Composition Explorer (NICER).
Dev R. Sadaula +2 more
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Search and Characterization of Remnant Radio Galaxies in the XMM-LSS Deep Field
The Astrophysical Journal, 2023 The remnant phase of a radio galaxy is characterized by the cessation of active galactic nuclei activity, resulting in the jets ceasing to feed plasma to the radio lobes.
Sushant Dutta +5 more
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The Merging Galaxy Cluster Environment Affects the Morphology of Radio Active Galactic Nuclei
The Astrophysical JournalIt has previously been found that the galaxy cluster environment can affect the fueling and evolution of active galactic nuclei (AGN). This work examines the effect of the merging cluster environment on the properties of radio AGN by comparing the radio ...
Mary Rickel +6 more
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NuSTAR Observes Two Bulgeless Galaxies: No Hard X-Ray AGN Detected in NGC 4178 or J0851+3926
The Astrophysical Journal, 2023 The discovery over the last several decades of low- and moderate-luminosity active galactic nuclei (AGNs) in disk-dominated galaxies—which show no “classical” bulges—suggests that secular mechanisms represent an important growth pathway for supermassive ...
Ryan W. Pfeifle +7 more
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The Astrophysical Journal LettersRecent James Webb Space Telescope observations have revealed a population of compact extragalactic objects at z ≳ 4 with red near-infrared colors, which have been dubbed as “Little Red Dots” (LRDs).
Minghao Yue +5 more
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The Astrophysical Journal Supplement SeriesWe present the active galactic nuclei (AGN) catalog from the fourth data release (HDR4) of the Hobby–Eberly Telescope Dark Energy Experiment Survey (HETDEX). HETDEX is an untargeted spectroscopic survey.
Chenxu Liu +9 more
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, 2010 This work represents the final year project for BSc Physics with Astrophysics degree and it mainly focuses on empirical investigation of the photometry of quasars in the Sloan Digital Sky Survey (SDSS) and the UK Infrared Telescope (UKIRT) Infrared Sky Survey (UKIDSS) systems.
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