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arXiv · 1204.5178

A Keck/LRIS Spatially-Resolved Spectroscopic Study of a LINER Galaxy SDSS J091628.05+420818.7

Hyun-Jin Bae·Jong-Hak Woo·Masafumi Yagi·Suk-Jin Yoon·Michitoshi Yoshida
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Abstract

Using spatially-resolved spectra obtained with the Low Resolution Imaging Spectrometer at the Keck I telescope, we investigate the nature of ionizing sources and kinematic properties of emission-line gas in a LINER galaxy SDSS J091628.05+420818.7, which is a nearby (z = 0.0241) and bright (M_r = -20.2) early-type galaxy. After subtracting stellar absorption features using a combination of simple stellar population models, we measure the flux, line-of-sight velocity, and velocity dispersion of four emission lines, i.e., H{\alpha}, H{\beta}, [O III] {\lambda}5007, and [N II] {\lambda}6584, to study radial change of emission-line fluxes and velocities. Compared to the point-spread-function of the observation, the emission-line region is slightly extended but comparable to the seeing size. The central concentration of emission-line gas suggests that ionization is triggered by a nuclear source, excluding old stellar population as ionizing sources. We find that emission-line gas is counter-rotating with respect to stellar component and that the [O III] {\lambda}5007 line is blueshifted compared to other emission lines, possibly due to an outflow.

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Hyun-Jin Bae, Jong-Hak Woo, Masafumi Yagi, Suk-Jin Yoon, Michitoshi Yoshida. 2012-04-23. A Keck/LRIS Spatially-Resolved Spectroscopic Study of a LINER Galaxy SDSS J091628.05+420818.7. https://doi.org/10.1088/0004-637x/753/1/10

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