THE POWER OF ADAPTIVE OPTICS - A CLOSE LOOK AT A MOLECULAR CLOUD IN NGC-2023

Citation
D. Rouan et al., THE POWER OF ADAPTIVE OPTICS - A CLOSE LOOK AT A MOLECULAR CLOUD IN NGC-2023, Monthly Notices of the Royal Astronomical Society, 284(2), 1997, pp. 395
Citations number
32
Categorie Soggetti
Astronomy & Astrophysics
ISSN journal
00358711
Volume
284
Issue
2
Year of publication
1997
Database
ISI
SICI code
0035-8711(1997)284:2<395:TPOAO->2.0.ZU;2-O
Abstract
Observations of the reflection nebula NGC 2023, a region of recent sta r formation, have revealed small-scale structure in the associated mol ecular cloud, close to the exciting star, at a spatial resolution of 5 0 to 75 au. These results have been obtained using adaptive optics on the ESO 3.6-m telescope at La Silla, observing in the H-2 upsilon = 1- 0 S(1) near-IR emission line at 2.121 mu m. Our observations are among the first to involve the use of adaptive optics combined with spectra l line resolution. The observed fragment of molecular cloud, a remnant of the material from which the B-star in NGC 2023 formed, contains a number of features whose H-2 emission brightness contrast to the surro unding material is an order of magnitude. These structures are interpr eted in terms of clumps of gas exhibiting a density contrast of at lea st an order of magnitude. We discuss the possibility that turbulence p lays a role in the creation of the observed structures.