NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-08-23 T13:25:40 PDT
Help | Comment | NED Home

For refcode 2018ApJ...869..138X:
Retrieve 24 NED objects in this reference.
Please click here for ADS abstract

NED Abstract

Copyright by American Astronomical Society. Reproduced by permission
2018ApJ...869..138X Spatially Resolved Spectroscopic Study of nearby Seyfert Galaxies: Implications for a Population of "Missed" Seyferts at High-z Xia, Junjie; Malkan, Matthew A.; Ross, Nathaniel R.; Ancheta, Agnes J. Abstract. We present mosaicked long-slit spectral maps of 18 nearby Active Galactic Nuclei (AGNs), 2 LINERs, and 4 star-forming galaxies. With the resulting data cubes taken using the Kast dual spectrograph on the 3 m Shane telescope of the Lick Observatory, we measure the aperture effects on the spectroscopic classification of AGNs. With more starlight included in a larger aperture, the nuclear spectrum that is Seyfert-like may become contaminated. We generated standard spectroscopic classification diagrams in different observing apertures. These show quantitatively how the ensemble of Seyferts migrates toward the H II region classification when being observed with increasing aperture sizes. But the effect ranges widely in individual active galaxies. Some of the less luminous Seyferts shift by a large amount, while some others barely move or even shift in different directions. We find that those Seyfert galaxies with the fraction of nuclear Halpha emission lower than 0.2 of the host galaxy, 2-10 keV hard X-ray luminosity lower than 10^43^ erg s^-1^, and the observed nuclear [O III] luminosity lower than 10^40.5^ erg s^-1^, are more likely to change activity classification type when the entire host galaxy is included. Overall, 4 of our 24 galaxies (18 Seyferts) change their spectral activity classification type when observed with a very large aperture. Key words: galaxies: active, galaxies: high-redshift, galaxies: nuclei, galaxies: Seyfert, galaxies: statistics, H II regions
Retrieve 24 NED objects in this reference.
Please click here for ADS abstract

Back to NED Home