Theory and observations of a jet in the _ orionis region: HH 444

The discovery of a system of Herbig{Haro objects ejected by young, low massstars in the Orionis region (Reipurth et al. 1998) has given rise to models of thephotoionization of a neutral jet by an external source.We present long{slit spectra of high spectral resolution of HH 444 and nu-merical simula...

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Detalles Bibliográficos
Autores: J. A. López, J. Meaburn, A. C. Raga, L. López Martin
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:57101018
Acceso en línea:https://www.redalyc.org/articulo.oa?id=57101018
Access Level:acceso abierto
Palabra clave:Física, Astronomía y Matemáticas
SHOCK WAVES
HYDRODYNAMICS
ISM: JETS AND OUTFLOWS
TECHNIQUES: SPECTROSCOPIC
ISM: INDIVIDUAL OBJECTS: HH 444
Descripción
Sumario:The discovery of a system of Herbig{Haro objects ejected by young, low massstars in the Orionis region (Reipurth et al. 1998) has given rise to models of thephotoionization of a neutral jet by an external source.We present long{slit spectra of high spectral resolution of HH 444 and nu-merical simulations for this Herbig{Haro object using \yguazu", a 3D gasdynamic+radiative transfer code (Raga et al. 1999). We nd that a velocity prole in thejet beam is necessary to explain the observed accelaration in the position{velocitydiagram of the HH jet. We also need also assume a non{zero opening angle at thebase of the jet to explain the decreasing H intensity at increasing distances fromthe source and a variable ejection velocity to reproduce the well separated knotsobserved along the jet.