The environs of the ultracompact HII region G45.45+0.06

Aims. G45.45+0.06 is an ultra-compact HII (UCHII) region that has been extensively studied. It is known that G45.45+0.06 is embedded in a complex of UCHII regions, but to date, the surrounding ISM on a larger spatial scale has not been analyzed. Methods. Using data from large-scale surveys, the Two...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Paron, S., Cichowolski, S., Ortega, M.E.
Formato: JOUR
Materias:
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_00046361_v506_n2_p789_Paron
Aporte de:
id todo:paper_00046361_v506_n2_p789_Paron
record_format dspace
spelling todo:paper_00046361_v506_n2_p789_Paron2023-10-03T14:00:28Z The environs of the ultracompact HII region G45.45+0.06 Paron, S. Cichowolski, S. Ortega, M.E. ISM: clouds ISM: HII regions Stars: formation All-sky survey H II regions ISM: clouds ISM: HII regions Main sequence stars Molecular gas Molecular materials Molecular shells Morphological correlations Multi-wavelength study Spatial scale Star formations Stars: formation Clouds Ionization of gases Surveys Stars Aims. G45.45+0.06 is an ultra-compact HII (UCHII) region that has been extensively studied. It is known that G45.45+0.06 is embedded in a complex of UCHII regions, but to date, the surrounding ISM on a larger spatial scale has not been analyzed. Methods. Using data from large-scale surveys, the Two Micron All Sky Survey, GLIMPSE, MIPSGAL, MAGPIS and GRS, we performed a multiwavelength study of a region of about 7' × 7' in the vicinity of G45.45+0.06. Results.We found that the UCHII complex lies on the border of a larger (diameter of ∼3') and fainter HII region, which is located at the same distance as G45.45+0.06, ∼8 kpc. In this work, this larger HII region is called G45L. A good morphological correlation is observed between the PDRs and the molecular gas mapped in the 13CO J = 1-0 and CS J = 2-1 lines, suggesting that G45L may be collecting molecular material. From a near- and mid-IR photometric study, we found three sources, likely O-type stars, that are possibly responsible for the creation of G45L. Additionally, we found several YSO candidates lying preferentially in the molecular shell that surrounds G45L. Our results confirm that the region southeast of the UCHII complex where G45.45+0.06 is embedded and east of G45L is undergoing active star formation. We suggest that G45L has been expanding for about 2 × 106 yr and could have triggered the formation of the zero-age main sequence stars that ionize the UCHII region G45.45+0.06. However we cannot discard that both HII regions are coeval. © 2009 ESO. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_00046361_v506_n2_p789_Paron
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic ISM: clouds
ISM: HII regions
Stars: formation
All-sky survey
H II regions
ISM: clouds
ISM: HII regions
Main sequence stars
Molecular gas
Molecular materials
Molecular shells
Morphological correlations
Multi-wavelength study
Spatial scale
Star formations
Stars: formation
Clouds
Ionization of gases
Surveys
Stars
spellingShingle ISM: clouds
ISM: HII regions
Stars: formation
All-sky survey
H II regions
ISM: clouds
ISM: HII regions
Main sequence stars
Molecular gas
Molecular materials
Molecular shells
Morphological correlations
Multi-wavelength study
Spatial scale
Star formations
Stars: formation
Clouds
Ionization of gases
Surveys
Stars
Paron, S.
Cichowolski, S.
Ortega, M.E.
The environs of the ultracompact HII region G45.45+0.06
topic_facet ISM: clouds
ISM: HII regions
Stars: formation
All-sky survey
H II regions
ISM: clouds
ISM: HII regions
Main sequence stars
Molecular gas
Molecular materials
Molecular shells
Morphological correlations
Multi-wavelength study
Spatial scale
Star formations
Stars: formation
Clouds
Ionization of gases
Surveys
Stars
description Aims. G45.45+0.06 is an ultra-compact HII (UCHII) region that has been extensively studied. It is known that G45.45+0.06 is embedded in a complex of UCHII regions, but to date, the surrounding ISM on a larger spatial scale has not been analyzed. Methods. Using data from large-scale surveys, the Two Micron All Sky Survey, GLIMPSE, MIPSGAL, MAGPIS and GRS, we performed a multiwavelength study of a region of about 7' × 7' in the vicinity of G45.45+0.06. Results.We found that the UCHII complex lies on the border of a larger (diameter of ∼3') and fainter HII region, which is located at the same distance as G45.45+0.06, ∼8 kpc. In this work, this larger HII region is called G45L. A good morphological correlation is observed between the PDRs and the molecular gas mapped in the 13CO J = 1-0 and CS J = 2-1 lines, suggesting that G45L may be collecting molecular material. From a near- and mid-IR photometric study, we found three sources, likely O-type stars, that are possibly responsible for the creation of G45L. Additionally, we found several YSO candidates lying preferentially in the molecular shell that surrounds G45L. Our results confirm that the region southeast of the UCHII complex where G45.45+0.06 is embedded and east of G45L is undergoing active star formation. We suggest that G45L has been expanding for about 2 × 106 yr and could have triggered the formation of the zero-age main sequence stars that ionize the UCHII region G45.45+0.06. However we cannot discard that both HII regions are coeval. © 2009 ESO.
format JOUR
author Paron, S.
Cichowolski, S.
Ortega, M.E.
author_facet Paron, S.
Cichowolski, S.
Ortega, M.E.
author_sort Paron, S.
title The environs of the ultracompact HII region G45.45+0.06
title_short The environs of the ultracompact HII region G45.45+0.06
title_full The environs of the ultracompact HII region G45.45+0.06
title_fullStr The environs of the ultracompact HII region G45.45+0.06
title_full_unstemmed The environs of the ultracompact HII region G45.45+0.06
title_sort environs of the ultracompact hii region g45.45+0.06
url http://hdl.handle.net/20.500.12110/paper_00046361_v506_n2_p789_Paron
work_keys_str_mv AT parons theenvironsoftheultracompacthiiregiong4545006
AT cichowolskis theenvironsoftheultracompacthiiregiong4545006
AT ortegame theenvironsoftheultracompacthiiregiong4545006
AT parons environsoftheultracompacthiiregiong4545006
AT cichowolskis environsoftheultracompacthiiregiong4545006
AT ortegame environsoftheultracompacthiiregiong4545006
_version_ 1807322564520837120