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Title: JWST Peers into the Class I Protostar TMC1A: Atomic Jet and Spatially Resolved Dissociative Shock Region
Abstract Outflows and winds launched from young stars play a crucial role in the evolution of protostars and the early stages of planet formation. However, the specific details of the mechanism behind these phenomena, including how they affect the protoplanetary disk structure, are still debated. We present JWST NIRSpec integral field unit observations of atomic and H2lines from 1 to 5.1μm toward the low-mass protostar TMC1A. For the first time, a collimated atomic jet is detected from TMC1A in the [Feii] line at 1.644μm along with corresponding extended H22.12μm emission. Toward the protostar, we detected spectrally broad Hiand Heiemissions with velocities up to 300 km s−1that can be explained by a combination of protostellar accretion and a wide-angle wind. The 2μm continuum dust emission, Hi, Hei, and Oiall show emission from the illuminated outflow cavity wall and scattered line emission. These observations demonstrate the potential of JWST to characterize and reveal new information about the hot inner regions of nearby protostars; in this case, a previously undetected atomic wind and ionized jet in a well-known outflow.  more » « less
Award ID(s):
1910106
PAR ID:
10549559
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
ApJ
Date Published:
Journal Name:
The Astrophysical Journal Letters
Volume:
951
Issue:
2
ISSN:
2041-8205
Page Range / eLocation ID:
L32
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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