12 mm line survey of the dense molecular gas towards the W28 field TeV gamma-ray sources

We present 12mm Mopra observations of dense molecular gas towards the W28 supernovaremnant (SNR) field. The focus is on the dense molecular gas towards the TeV gamma-raysources detected by the HESS telescopes, which likely trace the cosmic rays from W28 andpossibly other sources in the region. Using...

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Main Authors: Nicholas, B., Rowell, G., Burton, M., Walsh, Andrew, Fukui, Y., Kawamura, A., Longmore, S., Keto, E.
Format: Journal Article
Published: Oxford University Press 2010
Subjects:
Online Access:http://mnras.oxfordjournals.org/content/411/2/1367
http://hdl.handle.net/20.500.11937/25256
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author Nicholas, B.
Rowell, G.
Burton, M.
Walsh, Andrew
Fukui, Y.
Kawamura, A.
Longmore, S.
Keto, E.
author_facet Nicholas, B.
Rowell, G.
Burton, M.
Walsh, Andrew
Fukui, Y.
Kawamura, A.
Longmore, S.
Keto, E.
author_sort Nicholas, B.
building Curtin Institutional Repository
collection Online Access
description We present 12mm Mopra observations of dense molecular gas towards the W28 supernovaremnant (SNR) field. The focus is on the dense molecular gas towards the TeV gamma-raysources detected by the HESS telescopes, which likely trace the cosmic rays from W28 andpossibly other sources in the region. Using the NH3 inversion transitions we reveal severaldense cores inside the molecular clouds, the majority of which coincide with high-mass starformation and HII regions, including the energetic ultracompact HII region G5.89-0.39. Akey exception to this is the cloud north-east of W28, which is well known to be disruptedas evidenced by clusters of 1720MHz OH masers and broad CO line emission. Here wedetect broad NH3, up to the (9,9) transition, with linewidths up to 16 kms-1. This broad NH3emission spatially matches well with the TeV source HESS J1801-233 and CO emission, andits velocity dispersion distribution suggests external disruption from the W28 SNR direction.Other lines are detected, such as HC3Nand HC5N,H2Omasers, and many radio recombinationlines, all of which are primarily found towards the southern high-mass star formation regions.These observations provide a new view on to the internal structures and dynamics of thedense molecular gas towards the W28 SNR field and, in tandem with future higher-resolutionTeV gamma-ray observations, will offer the chance to probe the transport of cosmic rays intomolecular clouds.
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institution Curtin University Malaysia
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spelling curtin-20.500.11937-252562017-02-28T01:41:04Z 12 mm line survey of the dense molecular gas towards the W28 field TeV gamma-ray sources Nicholas, B. Rowell, G. Burton, M. Walsh, Andrew Fukui, Y. Kawamura, A. Longmore, S. Keto, E. clouds - HII regions radio lines individual gamma rays supernovae cosmic rays molecular data W28 ISM We present 12mm Mopra observations of dense molecular gas towards the W28 supernovaremnant (SNR) field. The focus is on the dense molecular gas towards the TeV gamma-raysources detected by the HESS telescopes, which likely trace the cosmic rays from W28 andpossibly other sources in the region. Using the NH3 inversion transitions we reveal severaldense cores inside the molecular clouds, the majority of which coincide with high-mass starformation and HII regions, including the energetic ultracompact HII region G5.89-0.39. Akey exception to this is the cloud north-east of W28, which is well known to be disruptedas evidenced by clusters of 1720MHz OH masers and broad CO line emission. Here wedetect broad NH3, up to the (9,9) transition, with linewidths up to 16 kms-1. This broad NH3emission spatially matches well with the TeV source HESS J1801-233 and CO emission, andits velocity dispersion distribution suggests external disruption from the W28 SNR direction.Other lines are detected, such as HC3Nand HC5N,H2Omasers, and many radio recombinationlines, all of which are primarily found towards the southern high-mass star formation regions.These observations provide a new view on to the internal structures and dynamics of thedense molecular gas towards the W28 SNR field and, in tandem with future higher-resolutionTeV gamma-ray observations, will offer the chance to probe the transport of cosmic rays intomolecular clouds. 2010 Journal Article http://hdl.handle.net/20.500.11937/25256 http://mnras.oxfordjournals.org/content/411/2/1367 Oxford University Press restricted
spellingShingle clouds
- HII regions
radio lines
individual
gamma rays
supernovae
cosmic rays
molecular data
W28
ISM
Nicholas, B.
Rowell, G.
Burton, M.
Walsh, Andrew
Fukui, Y.
Kawamura, A.
Longmore, S.
Keto, E.
12 mm line survey of the dense molecular gas towards the W28 field TeV gamma-ray sources
title 12 mm line survey of the dense molecular gas towards the W28 field TeV gamma-ray sources
title_full 12 mm line survey of the dense molecular gas towards the W28 field TeV gamma-ray sources
title_fullStr 12 mm line survey of the dense molecular gas towards the W28 field TeV gamma-ray sources
title_full_unstemmed 12 mm line survey of the dense molecular gas towards the W28 field TeV gamma-ray sources
title_short 12 mm line survey of the dense molecular gas towards the W28 field TeV gamma-ray sources
title_sort 12 mm line survey of the dense molecular gas towards the w28 field tev gamma-ray sources
topic clouds
- HII regions
radio lines
individual
gamma rays
supernovae
cosmic rays
molecular data
W28
ISM
url http://mnras.oxfordjournals.org/content/411/2/1367
http://hdl.handle.net/20.500.11937/25256