Revealing the active galactic nucleus in the superantennae through L-band spectroscopy
Astrophysics
2009-11-10 v1
Abstract
We present an L-band spectrum of the Ultraluminous Infrared Galaxy IRAS 19254-7245 (the Superantennae), obtained with VLT-ISAAC. The high signal to noise ratio allows a study of the main spectral features with unprecedented detail for an extragalactic source. We argue that the main energy source in the IR is an obscured AGN. This is indicated by the low equivalent width of the 3.3 micron PAH feature, the broad absorption feature at 3.4 um, and the steep continuum at lambda>3.7 um (f_lambda ~lambda^(2.7)). The substructure of the 3.4 um absorption feature indicates that the absorption is due to hydrocarbon chains of 6-7 carbon atoms.
Keywords
Cite
@article{arxiv.astro-ph/0308535,
title = {Revealing the active galactic nucleus in the superantennae through L-band spectroscopy},
author = {G. Risaliti and R. Maiolino and A. Marconi and L. Bassani and S. Berta and V. Braito and R. Della Ceca and A. Franceschini and M. Salvati},
journal= {arXiv preprint arXiv:astro-ph/0308535},
year = {2009}
}
Comments
12 pages, 3 figures. ApJ Letters, in press