The Open UniversitySkip to content
 

ISOCAM-CVF imaging of M 16

Urquhart, J. S.; White, Glenn J.; Pilbratt, G. L. and Fridlund, C. V. M. (2003). ISOCAM-CVF imaging of M 16. Astronomy & Astrophysics, 409(1) pp. 193–203.

DOI (Digital Object Identifier) Link: http://dx.doi.org/10.1051/0004-6361:20031076
Google Scholar: Look up in Google Scholar

Abstract

We present ISOCAM observations (5-17 μm) of the HST M 16 field, including the striking elephant trunk structures. The spectroscopic data have been obtained using the ISOCAM-CVF low-resolution mode, having a spectral resolution of ~40 (λ/Δλ) and a pixel size of 6". The spectra show a combination of Unidentified Infrared Band (UIB) emission centred at 6.2, 7.7, 8.6, 11.3 and 16.4 μ m, and atomic fine-structure lines of [ArII] 7.0 μm, [ArIII] 9.0 μm, [SIV] 10.5 μm, [NeII] 12.8 μm and [NeIII] 15.6 μm. The spectra were decomposed by fitting a combination of Lorentzian line profiles and a blackbody curve to the data to produce maps of the spatial distribution of the fine-structure and UIB emission features. These maps have been compared with VLA radio, 450 μm SCUBA maps, 12CO ( J = 1-0) maps, and broadband filters ISOCAM LW2 (5-8.5 μm) and LW3 (12-18 μm) observations. Decomposed spectral features have shown that the LW2 filter is dominated by UIB emission and the emission observed in the LW3 filter is a combination of Neon fine-structure lines and a steep continuum, with the continuum dominating. Using the photoionisation code CLOUDY we have produced theoretical values for the fine-structure ratio of [NeIII] 15.6 μm/[NeII] 12.8 μ m, from which we have calculated the effective ionising flux impinging onto the tips of the pillars to be ~ 1-3 x 10 10 photons cm -2 s -1, consistent with estimates made from VLA observations.

Item Type: Journal Article
Copyright Holders: 2003 ESO
ISSN: 1432-0746
Keywords: interstellar matter; HII regions; infrared lines and bands; Eagle Nebula
Academic Unit/Department: Science > Physical Sciences
Interdisciplinary Research Centre: Centre for Earth, Planetary, Space and Astronomical Research (CEPSAR)
Item ID: 31922
Depositing User: Glenn White
Date Deposited: 10 Feb 2012 14:56
Last Modified: 24 Sep 2014 13:25
URI: http://oro.open.ac.uk/id/eprint/31922
Share this page:

Altmetrics

Scopus Citations

Actions (login may be required)

View Item
Report issue / request change

Policies | Disclaimer

© The Open University   + 44 (0)870 333 4340   general-enquiries@open.ac.uk