Skip to main content Accessibility help
×
Home

Extended Carbon Emission in the Galaxy: Dark Gas along the G328 Sightline

Published online by Cambridge University Press:  12 September 2016


M. Burton
Affiliation:
School of Physics, University of New South Wales, Australia
M. Ashley
Affiliation:
School of Physics, University of New South Wales, Australia
C. Braiding
Affiliation:
School of Physics, University of New South Wales, Australia
M. Freeman
Affiliation:
School of Physics, University of New South Wales, Australia
C. Kulesa
Affiliation:
Steward Observatory, University of Arizona, USA
M. Wolfire
Affiliation:
Astronomy Department, University of Maryland, USA
D. Hollenbach
Affiliation:
Carl Sagan Center, SETI Institute, USA
G. Rowell
Affiliation:
School of Chemistry & Physics, University of Adelaide
J. Lau
Affiliation:
School of Chemistry & Physics, University of Adelaide

Abstract

We present spectral data cubes of the [CI] 809 GHz, 12CO 115 GHz, 13CO 110 GHz and HI 1.4 GHz line emission from a ~1° region along the l = 328° (G328) sightline in the Galactic Plane. The [CI] data comes from the High Elevation Antarctic Terahertz telescope at Ridge A on the summit of the Antarctic plateau, where the extremely low levels of precipitable water vapour open atmospheric windows for THz observations. The CO data comes from the Southern Galactic Plane Survey being conducted with the Mopra telescope. Emission arises principally from gas in three spiral arm crossings along the sight line. The distribution of the emission in the CO and [CI] lines is found to be similar, with the [CI] slightly more extended, and both are enveloped in extensive HI. Spectral line ratios are similar across the entire extent of the Galaxy. However, towards the edges of the molecular clouds the [CI]/13CO and 12CO/13CO line ratios rise by ~ 50%, and the [CI]/Hi ratio falls by ~ 10%. We attribute this to sightlines passing predominantly through the surfaces of photodissociation regions (PDRs), where the carbon is found mainly as C or C+ rather than CO, while the gas is mostly molecular. This is the signature of dark molecular gas.


Type
Poster Papers
Copyright
Copyright © International Astronomical Union 2015 

References

Burton, M. G., Ashley, M. C. B., Braiding, C., et al. 2014, ApJ, 782, 72 CrossRefGoogle Scholar
Burton, M. G., Ashley, M. C. B., Braiding, C., et al. 2015, ApJ, in press (arXiv:1508.04828)Google Scholar
Burton, M. G., Braiding, C., Glueck, C., et al. 2013, PASA, 30, e044 CrossRefGoogle Scholar
Braiding, C., Burton, M. G., Blackwell, R., et al. 2015, PASA, 32, e020 CrossRefGoogle Scholar
Vallée, J. P. 2014, AJ, 148, 5 CrossRefGoogle Scholar

Full text views

Full text views reflects PDF downloads, PDFs sent to Google Drive, Dropbox and Kindle and HTML full text views.

Total number of HTML views: 0
Total number of PDF views: 94 *
View data table for this chart

* Views captured on Cambridge Core between 12th September 2016 - 6th December 2020. This data will be updated every 24 hours.

Access
Hostname: page-component-b4dcdd7-pwkpp Total loading time: 0.904 Render date: 2020-12-06T02:28:38.335Z Query parameters: { "hasAccess": "1", "openAccess": "0", "isLogged": "0", "lang": "en" } Feature Flags last update: Sun Dec 06 2020 02:01:16 GMT+0000 (Coordinated Universal Time) Feature Flags: { "metrics": true, "metricsAbstractViews": false, "peerReview": true, "crossMark": true, "comments": true, "relatedCommentaries": true, "subject": true, "clr": false, "languageSwitch": true }

Send article to Kindle

To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about sending to your Kindle.

Note you can select to send to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

Extended Carbon Emission in the Galaxy: Dark Gas along the G328 Sightline
Available formats
×

Send article to Dropbox

To send this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Dropbox.

Extended Carbon Emission in the Galaxy: Dark Gas along the G328 Sightline
Available formats
×

Send article to Google Drive

To send this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Google Drive.

Extended Carbon Emission in the Galaxy: Dark Gas along the G328 Sightline
Available formats
×
×

Reply to: Submit a response


Your details


Conflicting interests

Do you have any conflicting interests? *