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Circumnuclear ionized gas in starburst nuclei
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Taniguchi, Yoshiaki |
| Copyright Year | 1990 |
| Description | In order to study kinematical properties of starburst nuclei (SBNs), researchers made high-resolution spectroscopy of fifteen SBNs in the H alpha region using an intensified Reticon system attached to the coude focus of the 188-cm reflector at the Okayama Astrophysical Observatory. The instrumental resolution is 21 km s(-1) Full Width Half Maximum (FWHM) at lambda sub H alpha. As for the archetypical SBN, Mrk 538 (=NGC 7714), researchers present high-resolution emission line profiles of several species of ions such as (OIII), (NII), (SII), and (OII). Main results and conclusions are summarized. It has been known that emission-line profiles of SBNs are symmetrical and narrow. However, this high-resolution spectroscopy shows that the observed emission-line profiles of the SBNs have the following asymmetrical patterns; blueward, redward, and double-peaked. It is known that such features have been observed for narrow line regions (NLRs) of active galactic nuclei (AGNs). There is no remarkable correlation between the asymmetry index and the reddening indicator such as a Balmer decrement. Thus the line asymmetry is not attributed to inhomogeneous obscuration in the emitting regions. The observed FWHMs of the H alpha emission lines cover a range from 85 km s(-1) to 318 km s(-1) and are slightly larger than those of (NII) lambda 6584A emission except for the double-peaked SBNs. The FWHMs of H alpha emission show a good correlation with sin i (i is an inclination angle of galaxy). This correlation means that the FWHMs of the SBNs suffer significantly from rotational broadening. Mrk 52 is an anomalous SBN because it has narrow emission line widths for its high inclination angle (cf. Taniguchi 1987). From the above correlation, it is estimated that the intrinsic (i.e., rotation free) FWHMs of H alpha emission are about 50 km s(-1). |
| File Size | 211061 |
| Page Count | 3 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19910004835 |
| Archival Resource Key | ark:/13960/t04z06b90 |
| Language | English |
| Publisher Date | 1990-07-01 |
| Access Restriction | Open |
| Subject Keyword | Astrophysics Stellar Spectra Ionized Gases Spectroscopy Correlation High Resolution Starburst Galaxies Estimating H Alpha Line Ions Stellar Evolution Rotation Reflectors Observatories Active Galactic Nuclei Asymmetry Occultation Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
