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Title: High-resolution Observations of H i in the IC 63 Reflection Nebula
Abstract

Photodissociation regions (PDRs), where the (far-)ultraviolet light from hot young stars interact with the gas in surrounding molecular clouds, provide laboratories for understanding the nature and role of feedback by star formation on the interstellar medium. While the general nature of PDRs is well understood—at least under simplified conditions—the detailed dynamics and chemistry of these regions, including gas clumping, evolution over time, etc., can be very complex. We present interferometric observations of the 21 cm atomic hydrogen line, combined with [Cii] 158μm observations, toward the nearby reflection nebula IC 63. We find a clumpy Histructure in the PDR, and a ring morphology for the Hiemission at the tip of IC 63. We further unveil kinematic substructure, of the order of 1 km s−1, in the PDR layers and several legs that will disperse IC 63 in <0.5 Myr. We find that the dynamics in the PDR explain the observed clumpy Hidistribution and lack of a well-defined Hi/H2transition front. However, it is currently not possible to conclude whether Hiself-absorption and nonequilibrium chemistry also contribute to this clumpy morphology and missing Hi/H2transition front.

 
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NSF-PAR ID:
10415077
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astronomical Journal
Volume:
165
Issue:
6
ISSN:
0004-6256
Format(s):
Medium: X Size: Article No. 243
Size(s):
Article No. 243
Sponsoring Org:
National Science Foundation
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