Results 21 to 30 of about 31,213 (262)
Black hole masses from emission‐line widths
Astronomische Nachrichten, Volume 343, Issue 1-2, January-February 2022., 2022 Abstract Reverberation mapping and scaling relationships based on reverberation results provide the underpinning of all estimates of quasar black hole masses. When applying these scaling relationships, there are potential pitfalls that are widely unappreciated and can result in biases that can, in turn, lead to systematic errors in the black hole mass ...
Elena Dalla Bontà, Bradley M. Peterson
wiley +1 more source
High‐Energy Neutrinos from the Cosmos
Annalen der Physik, Volume 533, Issue 11, November 2021., 2021 The IceCube Neutrino Observatory is the first detector of its kind, designed to observe the cosmos from deep within the South Pole ice. It consists of a cubic kilometer of instrumented transparent ice transformed into a Cherenkov detector. IceCube's first decade of operations has yielded breakthrough results, including the discovery of very high energy
Francis Halzen
wiley +1 more source
Overmassive Black Holes in Dwarf Galaxies Out to z ∼ 0.9 in the VIPERS Survey
The Astrophysical Journal Letters, 2023 Supermassive black holes (SMBHs) are thought to originate from early universe seed black holes of mass M _BH ∼ 10 ^2 –10 ^5 M _⊙ and grown through cosmic time. Such seeds could be powering the active galactic nuclei (AGN) found in today’s dwarf galaxies.
Mar Mezcua +5 more
doaj +1 more source
Peaked sources and narrow‐line Seyfert 1s: A love story
Astronomische Nachrichten, Volume 342, Issue 9-10, Page 1066-1070, November-December 2021., 2021 Abstract The first similarities between peaked sources (PS) and narrow‐line Seyfert 1 (NLS1) galaxies were noticed already 20 years ago. Nowadays, it is known that several sources can share both classifications, and that part of the parent population of γ‐ray emitting NLS1s could be hiding among PS.
Marco Berton, Emilia Järvelä
wiley +1 more source
AGN spiral galaxies in groups: effects of bars [PDF]
, 2014 We explore properties of barred active spiral galaxies in groups selected from the SDSS-DR7, with the aim of assessing the effects of bars on AGN and the role of the high density environment.
Alonso, Sol +2 more
core +4 more sources
The Astrophysical Journal, 2023 Pairs of galaxies hosting active galactic nuclei (AGNs) are powerful probes of merger-driven supermassive black hole (SMBH) growth as they can resolve individual AGNs and trace mergers over a large range of physical separations.
R. Scott Barrows +3 more
doaj +1 more source
The impact of young radio jets traced by cold molecular gas
Astronomische Nachrichten, Volume 342, Issue 9-10, Page 1135-1139, November-December 2021., 2021 Abstract Ranging from a few pc to hundreds of kpc in size, radio jets have, during their evolution, an impact on their gaseous environment on a large range of scales. While their effect on larger scales is well established, it is now becoming clear that they can also strongly affect the interstellar medium (ISM) inside the host galaxy.
Raffaella Morganti +3 more
wiley +1 more source
CLEAR: Spatially Resolved Emission Lines and Active Galactic Nuclei at 0.6 < z < 1.3
The Astrophysical Journal, 2023 We investigate spatially resolved emission-line ratios in a sample of 219 galaxies (0.6 < z < 1.3) detected using the G102 grism on the Hubble Space Telescope Wide Field Camera 3 taken as part of the CANDELS Ly α Emission at Reionization survey to ...
Bren E. Backhaus +10 more
doaj +1 more source
New Astronomy Reviews, 2008 A series of four lectures presented at the 2007 summer school on "Active Galactic Nuclei at the highest angular resolution: theory and observations" held in Torun, Poland.
openaire +2 more sources
Extremely inverted peaked spectrum radio sources
Astronomische Nachrichten, Volume 342, Issue 9-10, Page 1126-1129, November-December 2021., 2021 Abstract We report our ongoing search for extremely inverted spectrum compact radio galaxies, for which the defining feature in the radio spectrum is not the spectral peak, but instead the slope of the spectrum () in the high‐opacity (i.e., lower frequency) part of the radio spectrum.
Mukul Mhaskey +2 more
wiley +1 more source