The CII $158\,\mum$ fine-structure line is one of the dominant
coolants of the neutral interstellar medium. It is hence one of the brightest
far-infrared emission lines and can be observed not only in star-forming
regions throughout the Galaxy, but also in the diffuse interstellar medium and
in distant galaxies. CII line emission has been suggested to be a powerful
tracer of star-formation. We aim to understand the origin of CII emission and
its relation to other tracers of interstellar gas and dust. This includes a
study of the heating efficiency of interstellar gas as traced by the CII line
to test models of gas heating. We make use of a one-square-degree map of
velocity-resolved CII line emission towards the Orion Nebula complex,
including M43 and NGC 1977. The CII intensity is tightly correlated with PAH
emission in the IRAC $8\,\mum$ band and far-infrared emission from
warm dust. The correlation between CII and CO(2-1) is affected by the
detailed geometry of the region. We find particularly low CII-over-FIR
intensity ratios towards large columns of (warm and cold) dust, which suggest
the interpretation of the "CII deficit" in terms of a "FIR excess". A slight
decrease in the FIR line-over-continuum intensity ratio can be attributed to a
decreased heating efficiency of the gas. We find that, at the mapped spatial
scales, predictions of the star-formation rate from CII emission
underestimate the star-formation rate calculated from YSO counts in the Orion
Nebula complex by an order of magnitude. CII emission from the Orion Nebula
complex arises dominantly in the cloud surfaces, many viewed in edge-on
geometry. CII emission from extended faint cloud surfaces may contribute
significantly to the total CII emission on galactic scales.
Description
[CII] $158\,\mu\mathrm{m}$ line emission from Orion A. I. A template for extragalactic studies?
%0 Generic
%1 pabst2021158mumathrmm
%A Pabst, C. H. M.
%A Hacar, A.
%A Goicoechea, J. R.
%A Teyssier, D.
%A Berné, O.
%A Wolfire, M. G.
%A Higgins, R. D.
%A Chambers, E. T.
%A Kabanovic, S.
%A Güsten, R.
%A Stutzki, J.
%A Kramer, C.
%A Tielens, A. G. G. M.
%D 2021
%K library
%T CII $158\,\mum$ line emission from Orion A. I. A template for
extragalactic studies?
%U http://arxiv.org/abs/2105.03735
%X The CII $158\,\mum$ fine-structure line is one of the dominant
coolants of the neutral interstellar medium. It is hence one of the brightest
far-infrared emission lines and can be observed not only in star-forming
regions throughout the Galaxy, but also in the diffuse interstellar medium and
in distant galaxies. CII line emission has been suggested to be a powerful
tracer of star-formation. We aim to understand the origin of CII emission and
its relation to other tracers of interstellar gas and dust. This includes a
study of the heating efficiency of interstellar gas as traced by the CII line
to test models of gas heating. We make use of a one-square-degree map of
velocity-resolved CII line emission towards the Orion Nebula complex,
including M43 and NGC 1977. The CII intensity is tightly correlated with PAH
emission in the IRAC $8\,\mum$ band and far-infrared emission from
warm dust. The correlation between CII and CO(2-1) is affected by the
detailed geometry of the region. We find particularly low CII-over-FIR
intensity ratios towards large columns of (warm and cold) dust, which suggest
the interpretation of the "CII deficit" in terms of a "FIR excess". A slight
decrease in the FIR line-over-continuum intensity ratio can be attributed to a
decreased heating efficiency of the gas. We find that, at the mapped spatial
scales, predictions of the star-formation rate from CII emission
underestimate the star-formation rate calculated from YSO counts in the Orion
Nebula complex by an order of magnitude. CII emission from the Orion Nebula
complex arises dominantly in the cloud surfaces, many viewed in edge-on
geometry. CII emission from extended faint cloud surfaces may contribute
significantly to the total CII emission on galactic scales.
@misc{pabst2021158mumathrmm,
abstract = {The [CII] $158\,\mu\mathrm{m}$ fine-structure line is one of the dominant
coolants of the neutral interstellar medium. It is hence one of the brightest
far-infrared emission lines and can be observed not only in star-forming
regions throughout the Galaxy, but also in the diffuse interstellar medium and
in distant galaxies. [CII] line emission has been suggested to be a powerful
tracer of star-formation. We aim to understand the origin of [CII] emission and
its relation to other tracers of interstellar gas and dust. This includes a
study of the heating efficiency of interstellar gas as traced by the [CII] line
to test models of gas heating. We make use of a one-square-degree map of
velocity-resolved [CII] line emission towards the Orion Nebula complex,
including M43 and NGC 1977. The [CII] intensity is tightly correlated with PAH
emission in the IRAC $8\,\mu\mathrm{m}$ band and far-infrared emission from
warm dust. The correlation between [CII] and CO(2-1) is affected by the
detailed geometry of the region. We find particularly low [CII]-over-FIR
intensity ratios towards large columns of (warm and cold) dust, which suggest
the interpretation of the "[CII] deficit" in terms of a "FIR excess". A slight
decrease in the FIR line-over-continuum intensity ratio can be attributed to a
decreased heating efficiency of the gas. We find that, at the mapped spatial
scales, predictions of the star-formation rate from [CII] emission
underestimate the star-formation rate calculated from YSO counts in the Orion
Nebula complex by an order of magnitude. [CII] emission from the Orion Nebula
complex arises dominantly in the cloud surfaces, many viewed in edge-on
geometry. [CII] emission from extended faint cloud surfaces may contribute
significantly to the total [CII] emission on galactic scales.},
added-at = {2021-05-11T07:26:54.000+0200},
author = {Pabst, C. H. M. and Hacar, A. and Goicoechea, J. R. and Teyssier, D. and Berné, O. and Wolfire, M. G. and Higgins, R. D. and Chambers, E. T. and Kabanovic, S. and Güsten, R. and Stutzki, J. and Kramer, C. and Tielens, A. G. G. M.},
biburl = {https://www.bibsonomy.org/bibtex/2680cc7ebad67f0bd2e8777effe7b2902/gpkulkarni},
description = {[CII] $158\,\mu\mathrm{m}$ line emission from Orion A. I. A template for extragalactic studies?},
interhash = {c69e42369c6777c0d9f05bc1c7e58bb0},
intrahash = {680cc7ebad67f0bd2e8777effe7b2902},
keywords = {library},
note = {cite arxiv:2105.03735},
timestamp = {2021-05-11T07:26:54.000+0200},
title = {[CII] $158\,\mu\mathrm{m}$ line emission from Orion A. I. A template for
extragalactic studies?},
url = {http://arxiv.org/abs/2105.03735},
year = 2021
}