Abstract
Observations of the J = 2 → 1 and J = 5 → 4 transitions of SiO have been made toward the outflow source ∼1′.5 south of Orion-KL, using the IRAM 30 m telescope, with 25″ and 13″ resolution, respectively. Additional measurements of the J = 2 → 1, 3 → 2, and 5 → 4 lines of C34S and observations of J = 5 → 4 and J = 13 → 12 transitions of CH3CN have been made with the 30 m telescope. The SiO data clearly indicate that a separate outflow source exists ∼ 100″ S and 20″ W of the Orion-KL/IRc2 position, centered at α= 5h32m45s.4, δ= -5°26′5″.0 (1950.0). The outflow region has a FWHP size of ∼ 25″ and is bipolar in nature, the redshifted emission peaking ∼ 10″ S of the center and the blueshifted emission peaking 5″ N of center. The direction of the Orion-S flow is therefore NS, in contrast to Orion-KL, where the flow is oriented EW. The maximum outflow velocity (FWZP) is ∼ 25 km s-1. An LVG analysis of the SiO and CS data indicate that densities in the outflow are at least 3 × 105 cm-3. Kinetic temperatures derived from CH3CN are consistent with T ∼ 100 K. The Orion-S flow may be driven by a young, highly obscured star.
Original language | English (US) |
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Pages (from-to) | L25-L29 |
Journal | Astrophysical Journal |
Volume | 356 |
Issue number | 1 PART 2 |
DOIs | |
State | Published - Jun 10 1990 |
Keywords
- Interstellar: molecules
- Nebulae: Orion Nebula
- Stars: formation
- Stars: winds
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science