H2 Velocity Maps of Orion: Destruction of the Environment of the BN-KL Nebula

We present the velocity structure of the 2.12 micron H2 emission in Orion, obtained with an IR Fabry-Perot interferometer with a spectral resolution of 24 km/s and a 2arcsec spatial resolution, covering a region of 3.6´ by 3.6´ (0.46 by 0.46 pc2) that contains the H2 filamentary finger system. A sim...

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Detalles Bibliográficos
Autores: Luis Salas, Irene Cruz González, Leonel Gutiérrez, Jorge Valdez, Abel Bernal, Esteban Luna, Elfego Ruiz, Francisco Lazo, Margarita Rosado
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2001
País:México
Institución:Universidad Nacional Autónoma de México
Repositorio:Redalyc-UNAM
OAI Identifier:oai:redalyc.org:57101120
Acceso en línea:https://www.redalyc.org/articulo.oa?id=57101120
Access Level:acceso abierto
Palabra clave:Física, Astronomía y Matemáticas
Descripción
Sumario:We present the velocity structure of the 2.12 micron H2 emission in Orion, obtained with an IR Fabry-Perot interferometer with a spectral resolution of 24 km/s and a 2arcsec spatial resolution, covering a region of 3.6´ by 3.6´ (0.46 by 0.46 pc2) that contains the H2 filamentary finger system. A simple model is proposed to explain the observed low velocity structure as described by its radial moments: intensity, velocity centroid, velocity dispersion and skewness. We assume a strong wind of 230 km/s produced by IRc2 interacting with a set of molecular clumps with density of 5.6×105 cm-3. The scenario provides a good match to the observed moments is obtained, gives clues to the development of filaments or fingers and entrainment of the molecular material, and associates the observed high velocity blueshifted emission to the region. The H2 line emission is produced by a slow J-shock (20 km/s) in the clumps with an emissivity proportional to v1.8 . Estimates for the total wind mass and clumps mass yield 0.5 Msolar and 15 Msolar inside a radius of 1arcmin (0.1 pc). The individual clumps have masses and sizes of few × 10-3 Msolar and 0.007 pc, respectively. We conclude that the central 0.1 pc region surrounding the BN-KL nebula in front of OMC-1 is in the process of being disrupted by the strong wind of IRc2 on a time scale of 2000 yr.