A spectrophotometric study of the Seyfert 1 galaxy NGC 4253
Abstract
CCD spectroscopic observations from [NeV] lambda3425A to [SIII] lambda9532A of the nucleus and circumnuclear region of the Seyfert 1 NGC 4253 are presented. The nucleus shows circumnuclear emission which is elongated 1.5 kpc to the north-east; the spectrum of this extranuclear emission is well fitted by HII region models with effective temperatures of 50000K. The kinematics of the high-excitation gas is perturbed with respect to the low-ionization gas, showing radial motions compatible with an outflow wind. The nucleus is a strong FeII emitter, and its spectrum shows high-excitation lines, such as [FeVII] lambda6086A and [FeX] lambda6374A, which are produced by photoionization in the coronal-line region. Lines produced in high-density and low-ionization conditions, such as OI lambda8446A and MgII lambda9220A, are also detected; we show that these lines are produced by fluorescence with Lybeta. The near-infrared CaII triplet, detected in emission and in absorption, and the FeII emission are discussed in terms of the starburst model developed by Terlevich and collaborators.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- February 1996
- DOI:
- 10.1093/mnras/278.3.737
- Bibcode:
- 1996MNRAS.278..737G
- Keywords:
-
- LINE: IDENTIFICATION;
- GALAXIES: ACTIVE;
- GALAXIES: INDIVIDUAL: NGC 4253;
- GALAXIES: NUCLEI;
- GALAXIES: SEYFERT