Abstract
New infrared images of Cep A East are presented that show two regions of shock-excited line emission from separate bipolar flows. We identify the dominant sources powering the outflows and argue that the results support a multiple outflow model (Narayanan & Walker) as opposed to a quadrupolar outflow scenario. The images include near-infrared broadband (k [2.158 μm], L″ [3.81 μm], and M' [4.67 μm]) and spectral line ([Fe II] emission line at 1.644 μm and H2 1-0 S[1] line at 2.122 μm) observations, as well as continuum emission, at 1.644 μm and 2.122 μm Considering our data and other results, we present a unified, self-consistent picture of the disk and shock structure. The northern emission region appears to be the result of the ablation of a dense molecular clump (coincident with HW 6) in the path of a diverting jet from YSO HW 2 and subsequent multiple bow shocks with prompt entrainment arising from the interaction of the jet with the molecular cloud Cep A-2. The southern line emission region near H W 7 resembles the " artillery shell " bow shocks found in Orion and is most likely a J-type shock caused by a jet from another YSO, possibly HW 3(d)ii.
Original language | English (US) |
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Pages (from-to) | 359-374 |
Number of pages | 16 |
Journal | Astrophysical Journal |
Volume | 504 |
Issue number | 1 PART I |
DOIs | |
State | Published - 1998 |
Keywords
- H II regions
- ISM: individual (Cepheus A East)
- ISM: molecules
- Infrared: stars
- Stars: formation
- Stars: pre-main-sequence