Catching the Butterfly and the Homunculus of n Carinae with ALMA

The nature and origin of the molecular gas component located in the circumstellar vicinity of n Carinae are still far from being completely understood. Here, we present Atacama Large Millimeter/submillimeter Array CO(3-2) observations with a high angular resolution (∼0.″15) and a great sensitivity t...

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Detalles Bibliográficos
Autores: Zapata, Luis A., Loinard, Laurent, Fernandez Lopez, Manuel, Toalá, Jesús A., González, Ricardo F., Rodríguez, Luis F., Gull, Theodore R., Morris, Patrick W., Menten, Karl M., Kamiński, Tomasz
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2022
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/214007
Acceso en línea:http://hdl.handle.net/11336/214007
Access Level:acceso abierto
Palabra clave:Evolved stars
Astrophysics - Astrophysics of Galaxies
Astrophysics - Solar and Stellar Astrophysics
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Descripción
Sumario:The nature and origin of the molecular gas component located in the circumstellar vicinity of n Carinae are still far from being completely understood. Here, we present Atacama Large Millimeter/submillimeter Array CO(3-2) observations with a high angular resolution (∼0.″15) and a great sensitivity that are employed to reveal the origin of this component in n Carinae. These observations reveal much higher velocity (-300 to +270 km s-1) blue- and redshifted molecular thermal emission than previously reported, which we associate with the lobes of the Homunculus Nebula, and which delineates very well the innermost contours of the red- and blueshifted lobes likely due to limb brightening. The inner contour of the redshifted emission was proposed to be a disrupted torus, but here we reveal that it is at least part of the molecular emission originating from the lobes and/or the expanding equatorial skirt. On the other hand, closer to systemic velocities (±100 km s-1), the CO molecular gas traces an inner butterfly-shaped structure that is also revealed at near-IR and mid-IR wavelengths as the region in which the shielded dust resides. The location and kinematics of the molecular component indicate that this material has formed after the different eruptions of n Carinae.