Results 51 to 60 of about 166 (155)
Astronomische Nachrichten, Volume 346, Issue 3-4, March-May 2025.ABSTRACT The discovery of radio‐quiet, x‐ray thermally emitting isolated neutron stars (XINSs) in the ROSAT All‐Sky Survey revealed a previously overlooked component of the neutron star population. Advancements in x‐ray instrumentation and the availability of deep, wide‐area optical surveys now enable us to explore XINSs at fainter x‐ray fluxes and ...
Adriana Mancini Pires +11 more
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[$\ion{O}{iii}$] profile substructure in radio–quiet quasars [PDF]
Astronomy & Astrophysics, 2006 5 pages, 3 figures, accepted for publication in A& ...
Leipski, C., Bennert, N.
openaire +3 more sources
UEG Week 2022 Moderated Posters
, 2022 United European Gastroenterology Journal, Volume 10, Issue S8, Page 185-472, October 2022.
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A Surprising Excess of Radio Emission in Extremely Stable Quasars: A Unique Clue to Jet Launching?
The Astrophysical JournalQuasars are generally divided into jetted radio-loud and nonjetted radio-quiet ones, but why only 10% of quasars are radio-loud has been puzzling for decades.
Wen-Yong Kang +8 more
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Cosmic Supernova Neutrino and Gamma-Ray Backgrounds in the MeV Regime
The Astrophysical Journal, 2023 Cosmic multimessenger backgrounds include relic diffuse components created in the early universe and contributions from individual sources. Here, we study both type Ia supernovae (SNe Ia) and core-collapse supernovae (CCSNe) contributions to the diffuse ...
Samalka Anandagoda +6 more
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On the Cosmological Evolution of Radio Quiet and Radio Loud Quasars [PDF]
Symposium - International Astronomical Union, 1996 This contribution gives further insight into the problem of an ‘evolution’ of the function G(> R) [R is the ratio between radio and optical luminosity of a QSO] suggested by Visnovsky et al.(1992,ApJ,391,560), and recently by Schmidt et al.(1995,AJ,109,473). Using the Optical Luminosity Function for optically selected quasars derived by Boyle et al.(
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Evolution of the X‐ray Emission of Radio‐quiet Quasars [PDF]
The Astrophysical Journal, 2007 We report new Chandra observations of seven optically faint, z \sim 4 radio-quiet quasars. We have combined these new observations with previous Chandra observations of radio-quiet quasars to create a sample of 174 sources. These sources have 0.1 < z < 4.7, and 10^{44} ergs s^{-1} < nu L_{nu} (2500 Å) < 10^{48} ergs s^{-1}.
Kelly, Brandon C. +4 more
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Evidence of Gas Depletion in Quasars with Moderate Radio Emission
The Astrophysical JournalThe energy released by active galactic nuclei (AGNs) is considered to have a profound impact on the cold gas properties of their host galaxies, potentially heating or removing the gas and further suppressing star formation.
Yuhan Wen +6 more
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Astronomy & AstrophysicsAims. We study differences in the physical properties of quasar host galaxies using an optically selected sample of radio-loud (RL) and radio-quiet quasars (in the redshift range 0.15 ≤ z ≤ 1.9) that we have further cross-matched with the VLA-FIRST ...
Chakraborty Avinanda +6 more
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Probing extreme black‐hole outflows on short timescales via high spectral‐resolution x‐ray imagers
Astronomische Nachrichten, Volume 345, Issue 6-7, July-August 2024.Abstract We investigate outflows and the physics of super‐Eddington versus sub‐Eddington regimes in black hole systems. Our focus is on prospective science using next‐generation high‐resolution soft x‐ray instruments. We highlight the properties of black hole ultraluminous x‐ray source (ULX) systems in particular. Owing to scale invariance in accreting
C. Pinto +9 more
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