Protostars and Planets VI, Heidelberg, July 15-20, 2013

Poster 1K040

ALMA detection of a disk wind from HD 163296

Klaassen, Pamela (Leiden Observatory)
Juhasz, Attila (Leiden Observatory)
Mathews, Geoffrey (Leiden Observatory)
Mottram, Joseph (Leiden Observatory)
De Gregorio-Monsalvo, Itziar (JAO, ESO)
van Dishoeck, Ewine (Leiden Observatory, MPE)
Takahashi, Satoko (ASIAA)
Akiyama, Eiji (NAOJ)
Chapillon, Edwige (ASIAA)
Espada, Daniel (NAOJ)
Hales, Antonio (JAO)
Hogerheijde, Michiel (Leiden Observatory)
Rawlings, Mark (NRAO)
Schmalzl, Markus (Leiden Observatory)
Testi, Leonardo (ESO, INAF)

Disk winds have been postulated as a mechanism for angular momentum release in protostellar systems for decades. HD 163296 is a Herbig Ae star surrounded by a disk and has been shown to host a series of HH knots (HH 409) with bow shocks associated with the farthest knots. Here we present ALMA Science Verification data of CO J=2-1 and J=3-2 emission which are spatially coincident with the blue shifted jet of HH knots, and offset from the disk by -18.6 km/s. The emission has a double corkscrew morphology and extends more than 10\'\' from the disk with embedded emission clumps coincident with jet knots. We interpret this double corkscrew as emission from material in a molecular disk wind, and that the compact emission near the jet knots is being heated by the jet which is moving at much higher velocities. We show that the J=3-2 emission is likely heavily filtered by the interferometer, but the J=2-1 emission suffers less due to the larger beam and measurable angular scales. Excitation analysis suggests temperatures exceeding 900 K in these compact features. The high mass loss rate suggests that this star is dispersing the disk faster than it is funneling mass onto the star, signaling the end of the main accretion phase.

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