Results 11 to 20 of about 113,123 (219)
Multidimensional data-driven classification of emission-line galaxies [PDF]
Monthly Notices of the Royal Astronomical Society, 2019 We propose a new soft clustering scheme for classifying galaxies in different activity classes using simultaneously 4 emission-line ratios; log([NII ]/Ha), log([SII]/Ha), log([OI]/Ha) and log([OIII]/Hb). We fit 20 multivariate Gaussian distributions to the 4-dimensional distribution of these lines obtained from the Sloan Digital Sky Survey (SDSS) in ...
Stampoulis, V +3 more
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Spectral classification of emission-line galaxies [PDF]
The Astrophysical Journal Supplement Series, 1986 A revised method of classification of narrow-line active galaxies and H II region-like galaxies is proposed. It involves the line ratios which take full advantage of the physical distinction between the two types of objects and minimize the effects of reddening correction and errors in the flux calibration.
D. E. Osterbrock, S. Veilleux
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X-ray emission of galaxies with emission lines [PDF]
Astronomical School’s Report, 2011 We built new sample of 315 SDSS galaxies which were detected as X-ray sources in 2XMM catalog. On the basis of distribution of relative intensities of emission lines NII [6583] and OIII [5007] we divided objects of the sample into starburst galaxies and galaxies with active nuclei. Also we found distributions of X-ray luminosities of these galaxies.
A. V. Tugay, A. A. Vasylenko
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The Astrophysical Journal, 2023 Current methods of identifying the ionizing source of nebular emission in galaxies are well defined for the era of single-fiber spectroscopy, but still struggle to differentiate the complex and overlapping ionization sources in some galaxies.
Victor D. Johnston +13 more
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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
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Simulations of High-redshift [O iii] Emitters: Chemical Evolution and Multiline Diagnostics
The Astrophysical Journal, 2023 Recent observations by the James Webb Space Telescope discovered a number of high-redshift galaxies with strong emission lines from doubly ionized oxygen.
Yurina Nakazato +2 more
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AEGIS: Extinction and Star Formation Tracers from Line Emission [PDF]
, 2006 Strong nebular emission lines are a sensitive probe of star formation and extinction in galaxies, and the [O II] line detects star forming populations out to z>1.
A. C. Phillips +10 more
core +2 more sources
Searching for Emission-Line Galaxies [PDF]
International Astronomical Union Colloquium, 1984 Survey methods for finding emission-line galaxies are reviewed. Observational selection effects are investigated by comparing different surveys and the limitations of the different techniques are discussed. The advantages of Ha surveys for finding low luminosity galaxies and those with low excitation emission spectra are emphasized.
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Physical conditions of the interstellar medium in star-forming galaxies at z~1.5 [PDF]
, 2015 We present results from Subaru/FMOS near-infrared (NIR) spectroscopy of 118 star-forming galaxies at $z\sim1.5$ in the Subaru Deep Field. These galaxies are selected as [OII]$\lambda$3727 emitters at $z\approx$ 1.47 and 1.62 from narrow-band imaging.
Goto, Ryosuke +8 more
core +3 more sources
Classification and analysis of emission-line galaxies using mean field independent component analysis [PDF]
, 2013 We present an analysis of the optical spectra of narrow emission-line galaxies, based on mean field independent component analysis (MFICA). Samples of galaxies were drawn from the Sloan Digital Sky Survey (SDSS) and used to generate compact sets of ...
Allen, James T. +4 more
core +3 more sources