A spectrophotometric study of the Seyfert 1 galaxy NGC 4253

Gonzalez Delgado, Rosa M.; Perez, Enrique
Bibliographical reference

Monthly Notices of the Royal Astronomical Society, Volume 278, Issue 3, pp. 737-748.

Advertised on:
2
1996
Number of authors
2
IAC number of authors
1
Citations
20
Refereed citations
18
Description
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.