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Related papers: CLASS: Coronal Line Activity Spectroscopic Survey

200 papers

Some galaxies show little to no sign of active galactic nucleus (AGN) activity, yet exhibit strong coronal emission lines (CLs) relative to common narrow emission lines. Many of these CLs have ionization potentials of $\geq 100$ eV, thus…

High Energy Astrophysical Phenomena · Physics 2024-08-27 Jason T. Hinkle , Benjamin J. Shappee , Thomas W. -S. Holoien

Low-ionization nuclear emission-line regions (LINERs), which exist in a large fraction of galaxies, may be the least luminous manifestation of quasar activity. The nature of LINERs has, however, remained controversial because an AGN-like…

We report the discovery of a type IIn supernova in the low-metallicity dwarf galaxy J1320+2155, with an oxygen abundance 12+logO/H = 8.0+/-0.2. This finding is based on SDSS (February 2008) and 3.5m Apache Point Observatory (February 2009)…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Y. I. Izotov , T. X. Thuan

Many Seyfert galaxies display weak 'coronal' emission features corresponding to [Fe VII], [Fe XI] and [Fe XIV] in their optical spectra, whereas elsewhere these lines seem to be entirely absent. These lines appear to highlight zones in the…

Astrophysics of Galaxies · Physics 2016-04-18 Hartmut Winkler

A cross-correlation of the SDSS DR7 with the FIRST radio survey makes it possible to conduct a joined multiwavelength statistical study of radio-optical galaxy properties on a very large number of sources. Our goal is to improve the study…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 M. Vitale , J. Zuther , M. Garcia-Marin , A. Eckart , M. Bremer , M. Valencia-S. , A. Zensus

Low-Luminosity Active Galactic Nuclei (LLAGN) provides a unique view of Comptonization and non-thermal emission from accreting black holes in the low-accretion rate regime. However, to decipher the exact nature of the Comptonizing corona in…

In order to determine the incidence of black hole accretion-driven nuclear activity in nearby galaxies, as manifested by their radio emission, we have carried out a high-resolution Multi-Element Radio-Linked Interferometer Network (MERLIN)…

Astrophysics · Physics 2009-11-11 M. E. Filho , P. D. Barthel , L. C. Ho

We have obtained Keck NIR spectroscopy of a sample of nine M$_\star$ $<$ 10$^{10}$ M$_\odot$ dwarf galaxies to confirm AGN activity and the presence of galaxy-wide, AGN-driven outflows through coronal line (CL) emission. We find strong CL…

Astrophysics of Galaxies · Physics 2021-04-28 Thomas Bohn , Gabriela Canalizo , Sylvain Veilleux , Weizhe Liu

We have conducted a comprehensive mid-IR spectroscopic investigation of 67 Low Ionization Nuclear Emission Line Regions (LINERs) using archival observations from the high resolution modules of the Infrared Spectrograph on board the Spitzer…

Astrophysics · Physics 2014-11-18 R. P. Dudik , S. Satyapal , D. Marcu

We present an entirely new sample of 388 low-mass galaxies ($M_\star \leq 10^{10} M_\odot$) that have spectroscopic signatures indicating the presence of massive black holes (BHs) in the form of active galactic nuclei (AGNs) or tidal…

Astrophysics of Galaxies · Physics 2022-09-21 S. Salehirad , A. E. Reines , M. Molina

Local low metallicity galaxies with signatures of possible accretion activity are ideal laboratories in which to search for the lowest mass black holes and study their impact on the host galaxy. Here we present the first JWST NIRSpec IFS…

Active galactic nuclei (AGN) in low surface brightness galaxies (LSBGs) have received little attention in previous studies. In this paper, we present detailed spectral analysis of 194 LSBGs from the Impey et al. (1996) APM LSBG sample which…

Astrophysics of Galaxies · Physics 2009-11-13 Lin Mei , Weimin Yuan , Xiaobo Dong

We combine the catalogue of eclipsing binaries from the All Sky Automated Survey (ASAS) with the ROSAT All Sky Survey (RASS). The combination results in 836 eclipsing binaries that display coronal activity and is the largest sample of…

Astrophysics · Physics 2008-12-23 D. M. Szczygiel , A. Socrates , B. Paczynski , G. Pojmanski , B. Pilecki

Detecting active black holes in dwarf galaxies has proven to be a challenge due to their small size and weak electromagnetic signatures. Mid-infrared variability has emerged as a promising tool that can be used to detect active low-mass…

Astrophysics of Galaxies · Physics 2024-08-02 Archana Aravindan , Gabriela Canalizo , Nathan Secrest , Shobita Satyapal , Thomas Bohn

We combine emission line and X-ray luminosities for 45 sources from the Chandra Deep Field South (CDF-S), and seven HELLAS sources, to obtain a new sample of 52 X-ray selected type-II active galactic nuclei (AGNs). Eighteen of our sources…

Astrophysics · Physics 2009-11-11 Hagai Netzer , V. Mainieri , P. Rosati , Benny Trakhtenbrot

We report results from a deep Jansky Very Large Array (JVLA) search for CO 1-0 line emission from galaxies in a candidate galaxy cluster at z~1.55 in the COSMOS field. We target 4 galaxies with optical spectroscopic redshifts in the range…

Recent observations have revealed an interesting active galactic nuclei (AGN) subclass that shows strong activity at large scales ($\sim1$ kpc) but weaker at small scales ($<10$ pc), suggesting a strong change in the mass accretion rate of…

Astrophysics of Galaxies · Physics 2022-10-26 J. Pflugradt , K. Ichikawa , M. Akiyama , M. Kokubo , B. Vijarnwannaluk , H. Noda , X. Chen

An application of active contours without edges is presented as an efficient and effective means of extracting and characterizing coronal holes. Coronal holes are regions of low-density plasma on the Sun with open magnetic field lines. As…

Solar and Stellar Astrophysics · Physics 2016-10-05 L. E. Boucheron , M. Valluri , R. T. J. McAteer

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 \emph{Hubble Space Telescope} Wide Field Camera 3, taken as part of the CANDELS Ly$\alpha$ Emission at…