HST far-ultraviolet imaging of DG Tauri. Fluorescent molecular hydrogen emission from the wide opening-angle outflow

Autor(en)

P. C. Schneider, J. Eislöffel, M. Güdel, H. M. Günther, G. Herczeg, J. Robrade, J. H. M. M. Schmitt

Abstrakt

One of the most thoroughly studied jets from all young stellar objects

is the jet of DG Tau, which we imaged in the far-ultraviolet with the

Hubble Space Telescope for the first time. These high spatial resolution

images were obtained with long-pass filters and allow us to construct

images tracing mainly H2 and C iv emission. We find that the

H2 emission appears as a limb-brightened cone with additional

emission close to the jet axis. The length of the rims is about

0.″3 or 42 AU before their brightness strongly drops, and the

opening angle is about 90°. Comparing our far-ultraviolet data with

near-infrared data we find that the fluorescent H2 emission

probably traces the outer, cooler part of the disk wind while an origin

of the H2 emission in the surface layers (atmosphere) of the

(flared) disk is unlikely. Furthermore, the spatial shape of the

H2 emission shows little variation over six years which

suggests that the outer part of the disk wind is rather stable and

probably not associated with the formation of individual knots. The C iv

image shows that the emission is concentrated towards the jet axis. We

find no indications for additional C iv emission at larger distances,

which strengthens the association with the X-ray emission observed to

originate within the DG Tau jet.

Organisation(en)

Institut für Astrophysik

Externe Organisation(en)

Harvard-Smithsonian Center for Astrophysics, Thüringer Landessternwarte Tautenburg, Peking University, Universität Hamburg

Journal

Astronomy & Astrophysics

Band

557

Anzahl der Seiten

9

ISSN

0004-6361

DOI

https://doi.org/10.1051/0004-6361/201321564

Publikationsdatum

09-2013

Peer-reviewed

Ja

ÖFOS 2012

103004 Astrophysik, 103003 Astronomie

Schlagwörter

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