File Download
 
Links for fulltext
(May Require Subscription)
 
Supplementary

Article: 654 GHz continuum and C 18O(6-5) observations of G240.31+0.07 with the submillimeter array
  • Basic View
  • Metadata View
  • XML View
Title654 GHz continuum and C 18O(6-5) observations of G240.31+0.07 with the submillimeter array
 
AuthorsChen, HR3 1
Su, YN1
Liu, SY1
Hunter, TR2
Wilner, DJ2
Zhang, Q2
Lim, J1
Ho, PTP1 2
Ohashi, N1
Hirano, N1
 
KeywordsCircumstellar Matter
Stars: Early-Type - Stars: Individual (G240.31+0.07)
Stars: Pre-Main-Sequence
Submillimeter
Techniques: Interferometric
 
Issue Date2007
 
PublisherInstitute of Physics Publishing Ltd. The Journal's web site is located at http://iopscience.iop.org/2041-8205
 
CitationAstrophysical Journal Letters, 2007, v. 654 n. 1 II, p. L87-L90 [How to Cite?]
DOI: http://dx.doi.org/10.1086/510715
 
AbstractWe report a dual-band observation at 223 and 654 GHz (460 μm) toward an ultracompact (UC) H II region, G240.31+0.07, using the Submillimeter Array. With a beam size of 1.5″ × 0.8″, the dust continuum emission is resolved into two clumps, with clump A well coincident with an H 2O maser and the UC H II region. The newly discovered clump, B, about 1.3″ (≃8.3 × 10 3 AU) to the southwest of clump A, is also associated with H 2O masers and may be a more recent star-forming site. The continuum flux densities imply an opacity spectral index of β = 1.5 ± 0.3, suggestive of a value lower than the canonical 2.0 found in the interstellar medium and in cold, massive cores. The presence of hot (≃100 K) molecular gas is derived by the brightness ratio of two H 2CO lines in the 223 GHz band. A radial velocity difference of 2.5 ± 0.4 km s -1 is found between the two clumps in C 18O(6-5) emission. The total (nebular and stellar) mass of roughly 58 M ⊙ in the central region is close to, but not much larger than, the minimum mass required for the two clumps to be gravitationally bound for binary rotation. Our continuum data do not suggest a large amount of matter associated with the H 2 knots that were previously proposed to arise from a massive disk or envelope. © 2007. The American Astronomical Society. All rights reserved.
 
ISSN2041-8205
2012 Impact Factor: 6.345
 
DOIhttp://dx.doi.org/10.1086/510715
 
ReferencesReferences in Scopus
 
DC FieldValue
dc.contributor.authorChen, HR
 
dc.contributor.authorSu, YN
 
dc.contributor.authorLiu, SY
 
dc.contributor.authorHunter, TR
 
dc.contributor.authorWilner, DJ
 
dc.contributor.authorZhang, Q
 
dc.contributor.authorLim, J
 
dc.contributor.authorHo, PTP
 
dc.contributor.authorOhashi, N
 
dc.contributor.authorHirano, N
 
dc.date.accessioned2012-11-26T08:48:59Z
 
dc.date.available2012-11-26T08:48:59Z
 
dc.date.issued2007
 
dc.description.abstractWe report a dual-band observation at 223 and 654 GHz (460 μm) toward an ultracompact (UC) H II region, G240.31+0.07, using the Submillimeter Array. With a beam size of 1.5″ × 0.8″, the dust continuum emission is resolved into two clumps, with clump A well coincident with an H 2O maser and the UC H II region. The newly discovered clump, B, about 1.3″ (≃8.3 × 10 3 AU) to the southwest of clump A, is also associated with H 2O masers and may be a more recent star-forming site. The continuum flux densities imply an opacity spectral index of β = 1.5 ± 0.3, suggestive of a value lower than the canonical 2.0 found in the interstellar medium and in cold, massive cores. The presence of hot (≃100 K) molecular gas is derived by the brightness ratio of two H 2CO lines in the 223 GHz band. A radial velocity difference of 2.5 ± 0.4 km s -1 is found between the two clumps in C 18O(6-5) emission. The total (nebular and stellar) mass of roughly 58 M ⊙ in the central region is close to, but not much larger than, the minimum mass required for the two clumps to be gravitationally bound for binary rotation. Our continuum data do not suggest a large amount of matter associated with the H 2 knots that were previously proposed to arise from a massive disk or envelope. © 2007. The American Astronomical Society. All rights reserved.
 
dc.description.natureLink_to_subscribed_fulltext
 
dc.identifier.citationAstrophysical Journal Letters, 2007, v. 654 n. 1 II, p. L87-L90 [How to Cite?]
DOI: http://dx.doi.org/10.1086/510715
 
dc.identifier.doihttp://dx.doi.org/10.1086/510715
 
dc.identifier.epageL90
 
dc.identifier.issn2041-8205
2012 Impact Factor: 6.345
 
dc.identifier.issue1 II
 
dc.identifier.scopuseid_2-s2.0-33846543229
 
dc.identifier.spageL87
 
dc.identifier.urihttp://hdl.handle.net/10722/175051
 
dc.identifier.volume654
 
dc.languageeng
 
dc.publisherInstitute of Physics Publishing Ltd. The Journal's web site is located at http://iopscience.iop.org/2041-8205
 
dc.publisher.placeUnited Kingdom
 
dc.relation.ispartofAstrophysical Journal Letters
 
dc.relation.referencesReferences in Scopus
 
dc.subjectCircumstellar Matter
 
dc.subjectStars: Early-Type - Stars: Individual (G240.31+0.07)
 
dc.subjectStars: Pre-Main-Sequence
 
dc.subjectSubmillimeter
 
dc.subjectTechniques: Interferometric
 
dc.title654 GHz continuum and C 18O(6-5) observations of G240.31+0.07 with the submillimeter array
 
dc.typeArticle
 
<?xml encoding="utf-8" version="1.0"?>
<item><contributor.author>Chen, HR</contributor.author>
<contributor.author>Su, YN</contributor.author>
<contributor.author>Liu, SY</contributor.author>
<contributor.author>Hunter, TR</contributor.author>
<contributor.author>Wilner, DJ</contributor.author>
<contributor.author>Zhang, Q</contributor.author>
<contributor.author>Lim, J</contributor.author>
<contributor.author>Ho, PTP</contributor.author>
<contributor.author>Ohashi, N</contributor.author>
<contributor.author>Hirano, N</contributor.author>
<date.accessioned>2012-11-26T08:48:59Z</date.accessioned>
<date.available>2012-11-26T08:48:59Z</date.available>
<date.issued>2007</date.issued>
<identifier.citation>Astrophysical Journal Letters, 2007, v. 654 n. 1 II, p. L87-L90</identifier.citation>
<identifier.issn>2041-8205</identifier.issn>
<identifier.uri>http://hdl.handle.net/10722/175051</identifier.uri>
<description.abstract>We report a dual-band observation at 223 and 654 GHz (460 &#956;m) toward an ultracompact (UC) H II region, G240.31+0.07, using the Submillimeter Array. With a beam size of 1.5&#8243; &#215; 0.8&#8243;, the dust continuum emission is resolved into two clumps, with clump A well coincident with an H 2O maser and the UC H II region. The newly discovered clump, B, about 1.3&#8243; (&#8771;8.3 &#215; 10 3 AU) to the southwest of clump A, is also associated with H 2O masers and may be a more recent star-forming site. The continuum flux densities imply an opacity spectral index of &#946; = 1.5 &#177; 0.3, suggestive of a value lower than the canonical 2.0 found in the interstellar medium and in cold, massive cores. The presence of hot (&#8771;100 K) molecular gas is derived by the brightness ratio of two H 2CO lines in the 223 GHz band. A radial velocity difference of 2.5 &#177; 0.4 km s -1 is found between the two clumps in C 18O(6-5) emission. The total (nebular and stellar) mass of roughly 58 M &#8857; in the central region is close to, but not much larger than, the minimum mass required for the two clumps to be gravitationally bound for binary rotation. Our continuum data do not suggest a large amount of matter associated with the H 2 knots that were previously proposed to arise from a massive disk or envelope. &#169; 2007. The American Astronomical Society. All rights reserved.</description.abstract>
<language>eng</language>
<publisher>Institute of Physics Publishing Ltd. The Journal&apos;s web site is located at http://iopscience.iop.org/2041-8205</publisher>
<relation.ispartof>Astrophysical Journal Letters</relation.ispartof>
<subject>Circumstellar Matter</subject>
<subject>Stars: Early-Type - Stars: Individual (G240.31+0.07)</subject>
<subject>Stars: Pre-Main-Sequence</subject>
<subject>Submillimeter</subject>
<subject>Techniques: Interferometric</subject>
<title>654 GHz continuum and C 18O(6-5) observations of G240.31+0.07 with the submillimeter array</title>
<type>Article</type>
<description.nature>Link_to_subscribed_fulltext</description.nature>
<identifier.doi>10.1086/510715</identifier.doi>
<identifier.scopus>eid_2-s2.0-33846543229</identifier.scopus>
<relation.references>http://www.scopus.com/mlt/select.url?eid=2-s2.0-33846543229&amp;selection=ref&amp;src=s&amp;origin=recordpage</relation.references>
<identifier.volume>654</identifier.volume>
<identifier.issue>1 II</identifier.issue>
<identifier.spage>L87</identifier.spage>
<identifier.epage>L90</identifier.epage>
<publisher.place>United Kingdom</publisher.place>
</item>
Author Affiliations
  1. Institute of Astrophysics and Astronomy, Academia Sinica Taiwan
  2. Harvard-Smithsonian Center for Astrophysics
  3. National Tsing Hua University