Molecular gas toward G18.8+1.8

Autores
Vasquez, Javier; Rubio, Mónica; Cappa, Cristina Elisabet; Duronea, Nicolás Urbano
Año de publicación
2012
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
Aims. This work aims at investigating the characteristics of the molecular gas associated with the nebula G18.8+1.8, which is linked to the Wolf-Rayet star HD 168206 (WR 113), and its relation to other components of its local interstellar medium. Methods. We carried out molecular observations of the 12CO(J = 1-0) and (J = 2-1) lines with an angular resolution of 44′′ and 22′′ using the SEST telescope. Complementary NANTEN data of the 12CO(1-0) line were also used. The dust emission was analyzed using Spitzer-IRAC images at 8.0 μm, and WISE data at 3.4 μm, 4.6 μm, and 12.0 μm. Results. The SEST data allowed us to identify a molecular component (Cloud 3) that has velocities in the interval from ~+30 to +36 km s -1 and is most probably linked to the nebula. Morphological and kinematical properties suggest that Cloud 3 consists of a wind-blown molecular half-shell, which expands around WR 113. The ratio R2-1/1-0 and excitation temperatures indicate that the molecular gas is being irradiated by strong UV radiation. The location of the inner optical ring in the outer edge of Cloud 3 suggests that the stars SerOB2-1,-2,-3,-63, and-64 are responsables for the ionization of Cloud 3 and the inner ring nebula. A comparison between the spatial distribution of the molecular gas and the PAH emission at 8 μm indicates the existence of a photodissociation region between the ionized and the molecular gas. A search for candidate young stellar objects (YSOs) in the region around G18.8+1.8 based on available 2MASS, MSX, IRAS, and Spitzer-IRAC catalogs resulted in the detection of about sixty sources, some of them projected onto Cloud 3. Two small spots of clustered candidate YSOs are projected near the outer border of Cloud 3, although a triggered stellar formation scenario is doubtful.
Facultad de Ciencias Astronómicas y Geofísicas
Instituto Argentino de Radioastronomía
Materia
Ciencias Astronómicas
ISM: bubbles
ISM: individual objects: G18.8+1.8
Stars: individual: WR 113
Stars: Wolf-Rayet
Nivel de accesibilidad
acceso abierto
Condiciones de uso
http://creativecommons.org/licenses/by-nc-sa/4.0/
Repositorio
SEDICI (UNLP)
Institución
Universidad Nacional de La Plata
OAI Identificador
oai:sedici.unlp.edu.ar:10915/84059
Acceder
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oai_identifier_str oai:sedici.unlp.edu.ar:10915/84059
network_acronym_str SEDICI
repository_id_str 1329
network_name_str SEDICI (UNLP)
spelling Molecular gas toward G18.8+1.8Vasquez, JavierRubio, MónicaCappa, Cristina ElisabetDuronea, Nicolás UrbanoCiencias AstronómicasISM: bubblesISM: individual objects: G18.8+1.8Stars: individual: WR 113Stars: Wolf-RayetAims. This work aims at investigating the characteristics of the molecular gas associated with the nebula G18.8+1.8, which is linked to the Wolf-Rayet star HD 168206 (WR 113), and its relation to other components of its local interstellar medium. Methods. We carried out molecular observations of the <SUP>12</SUP>CO(J = 1-0) and (J = 2-1) lines with an angular resolution of 44′′ and 22′′ using the SEST telescope. Complementary NANTEN data of the <SUP>12</SUP>CO(1-0) line were also used. The dust emission was analyzed using <i>Spitzer</i>-IRAC images at 8.0 μm, and WISE data at 3.4 μm, 4.6 μm, and 12.0 μm. Results. The SEST data allowed us to identify a molecular component (Cloud 3) that has velocities in the interval from ~+30 to +36 km s <SUP>-1</SUP> and is most probably linked to the nebula. Morphological and kinematical properties suggest that Cloud 3 consists of a wind-blown molecular half-shell, which expands around WR 113. The ratio R<SUB>2-1/1-0</SUB> and excitation temperatures indicate that the molecular gas is being irradiated by strong UV radiation. The location of the inner optical ring in the outer edge of Cloud 3 suggests that the stars SerOB2-1,-2,-3,-63, and-64 are responsables for the ionization of Cloud 3 and the inner ring nebula. A comparison between the spatial distribution of the molecular gas and the PAH emission at 8 μm indicates the existence of a photodissociation region between the ionized and the molecular gas. A search for candidate young stellar objects (YSOs) in the region around G18.8+1.8 based on available 2MASS, MSX, IRAS, and <i>Spitzer</i>-IRAC catalogs resulted in the detection of about sixty sources, some of them projected onto Cloud 3. Two small spots of clustered candidate YSOs are projected near the outer border of Cloud 3, although a triggered stellar formation scenario is doubtful.Facultad de Ciencias Astronómicas y GeofísicasInstituto Argentino de Radioastronomía2012info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionArticulohttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfhttp://sedici.unlp.edu.ar/handle/10915/84059enginfo:eu-repo/semantics/altIdentifier/issn/0004-6361info:eu-repo/semantics/altIdentifier/doi/10.1051/0004-6361/201219147info:eu-repo/semantics/openAccesshttp://creativecommons.org/licenses/by-nc-sa/4.0/Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)reponame:SEDICI (UNLP)instname:Universidad Nacional de La Platainstacron:UNLP2025-10-22T16:56:52Zoai:sedici.unlp.edu.ar:10915/84059Institucionalhttp://sedici.unlp.edu.ar/Universidad públicaNo correspondehttp://sedici.unlp.edu.ar/oai/snrdalira@sedici.unlp.edu.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:13292025-10-22 16:56:52.369SEDICI (UNLP) - Universidad Nacional de La Platafalse
dc.title.none.fl_str_mv Molecular gas toward G18.8+1.8
title Molecular gas toward G18.8+1.8
spellingShingle Molecular gas toward G18.8+1.8
Vasquez, Javier
Ciencias Astronómicas
ISM: bubbles
ISM: individual objects: G18.8+1.8
Stars: individual: WR 113
Stars: Wolf-Rayet
title_short Molecular gas toward G18.8+1.8
title_full Molecular gas toward G18.8+1.8
title_fullStr Molecular gas toward G18.8+1.8
title_full_unstemmed Molecular gas toward G18.8+1.8
title_sort Molecular gas toward G18.8+1.8
dc.creator.none.fl_str_mv Vasquez, Javier
Rubio, Mónica
Cappa, Cristina Elisabet
Duronea, Nicolás Urbano
author Vasquez, Javier
author_facet Vasquez, Javier
Rubio, Mónica
Cappa, Cristina Elisabet
Duronea, Nicolás Urbano
author_role author
author2 Rubio, Mónica
Cappa, Cristina Elisabet
Duronea, Nicolás Urbano
author2_role author
author
author
dc.subject.none.fl_str_mv Ciencias Astronómicas
ISM: bubbles
ISM: individual objects: G18.8+1.8
Stars: individual: WR 113
Stars: Wolf-Rayet
topic Ciencias Astronómicas
ISM: bubbles
ISM: individual objects: G18.8+1.8
Stars: individual: WR 113
Stars: Wolf-Rayet
dc.description.none.fl_txt_mv Aims. This work aims at investigating the characteristics of the molecular gas associated with the nebula G18.8+1.8, which is linked to the Wolf-Rayet star HD 168206 (WR 113), and its relation to other components of its local interstellar medium. Methods. We carried out molecular observations of the <SUP>12</SUP>CO(J = 1-0) and (J = 2-1) lines with an angular resolution of 44′′ and 22′′ using the SEST telescope. Complementary NANTEN data of the <SUP>12</SUP>CO(1-0) line were also used. The dust emission was analyzed using <i>Spitzer</i>-IRAC images at 8.0 μm, and WISE data at 3.4 μm, 4.6 μm, and 12.0 μm. Results. The SEST data allowed us to identify a molecular component (Cloud 3) that has velocities in the interval from ~+30 to +36 km s <SUP>-1</SUP> and is most probably linked to the nebula. Morphological and kinematical properties suggest that Cloud 3 consists of a wind-blown molecular half-shell, which expands around WR 113. The ratio R<SUB>2-1/1-0</SUB> and excitation temperatures indicate that the molecular gas is being irradiated by strong UV radiation. The location of the inner optical ring in the outer edge of Cloud 3 suggests that the stars SerOB2-1,-2,-3,-63, and-64 are responsables for the ionization of Cloud 3 and the inner ring nebula. A comparison between the spatial distribution of the molecular gas and the PAH emission at 8 μm indicates the existence of a photodissociation region between the ionized and the molecular gas. A search for candidate young stellar objects (YSOs) in the region around G18.8+1.8 based on available 2MASS, MSX, IRAS, and <i>Spitzer</i>-IRAC catalogs resulted in the detection of about sixty sources, some of them projected onto Cloud 3. Two small spots of clustered candidate YSOs are projected near the outer border of Cloud 3, although a triggered stellar formation scenario is doubtful.
Facultad de Ciencias Astronómicas y Geofísicas
Instituto Argentino de Radioastronomía
description Aims. This work aims at investigating the characteristics of the molecular gas associated with the nebula G18.8+1.8, which is linked to the Wolf-Rayet star HD 168206 (WR 113), and its relation to other components of its local interstellar medium. Methods. We carried out molecular observations of the <SUP>12</SUP>CO(J = 1-0) and (J = 2-1) lines with an angular resolution of 44′′ and 22′′ using the SEST telescope. Complementary NANTEN data of the <SUP>12</SUP>CO(1-0) line were also used. The dust emission was analyzed using <i>Spitzer</i>-IRAC images at 8.0 μm, and WISE data at 3.4 μm, 4.6 μm, and 12.0 μm. Results. The SEST data allowed us to identify a molecular component (Cloud 3) that has velocities in the interval from ~+30 to +36 km s <SUP>-1</SUP> and is most probably linked to the nebula. Morphological and kinematical properties suggest that Cloud 3 consists of a wind-blown molecular half-shell, which expands around WR 113. The ratio R<SUB>2-1/1-0</SUB> and excitation temperatures indicate that the molecular gas is being irradiated by strong UV radiation. The location of the inner optical ring in the outer edge of Cloud 3 suggests that the stars SerOB2-1,-2,-3,-63, and-64 are responsables for the ionization of Cloud 3 and the inner ring nebula. A comparison between the spatial distribution of the molecular gas and the PAH emission at 8 μm indicates the existence of a photodissociation region between the ionized and the molecular gas. A search for candidate young stellar objects (YSOs) in the region around G18.8+1.8 based on available 2MASS, MSX, IRAS, and <i>Spitzer</i>-IRAC catalogs resulted in the detection of about sixty sources, some of them projected onto Cloud 3. Two small spots of clustered candidate YSOs are projected near the outer border of Cloud 3, although a triggered stellar formation scenario is doubtful.
publishDate 2012
dc.date.none.fl_str_mv 2012
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
Articulo
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info:ar-repo/semantics/articulo
format article
status_str publishedVersion
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language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/issn/0004-6361
info:eu-repo/semantics/altIdentifier/doi/10.1051/0004-6361/201219147
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-sa/4.0/
Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)
eu_rights_str_mv openAccess
rights_invalid_str_mv http://creativecommons.org/licenses/by-nc-sa/4.0/
Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)
dc.format.none.fl_str_mv application/pdf
dc.source.none.fl_str_mv reponame:SEDICI (UNLP)
instname:Universidad Nacional de La Plata
instacron:UNLP
reponame_str SEDICI (UNLP)
collection SEDICI (UNLP)
instname_str Universidad Nacional de La Plata
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repository.name.fl_str_mv SEDICI (UNLP) - Universidad Nacional de La Plata
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