Characterizing the Youngest Herschel-detected Protostars II. Molecular Outflows from the Millimeter and the Far-infrared

John J. Tobin; Amelia M. Stutz; P. Manoj; S. Thomas Megeath; Agata Karska; Zsofia Nagy; Friedrich Wyrowski; William Fischer; Dan M. Watson; Thomas Stanke

doi:10.3847/0004-637x/831/1/36

arXiv · 1607.00787

Characterizing the Youngest Herschel-detected Protostars II. Molecular Outflows from the Millimeter and the Far-infrared

John J. Tobin·Amelia M. Stutz·P. Manoj·S. Thomas Megeath·Agata Karska·Zsofia Nagy·Friedrich Wyrowski·William Fischer·Dan M. Watson·Thomas Stanke

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Abstract

We present CARMA CO (J=1-0) observations and Herschel PACS spectroscopy, characterizing the outflow properties toward extremely young and deeply embedded protostars in the Orion molecular clouds. The sample comprises a subset of the Orion protostars known as the PACS Bright Red Sources (PBRS) (Stutz et al. 2013). We observed 14 PBRS with CARMA and 8 of these 14 with Herschel, acquiring full spectral scans from 55 micron to 200 micron. Outflows are detected in CO (J=1-0) from 8 of 14 PBRS, with two additional tentative detections; outflows are also detected from the outbursting protostar HOPS 223 (V2775 Ori) and the Class I protostar HOPS 68. The outflows have a range of morphologies, some are spatially compact, <10000 AU in extent, while others extend beyond the primary beam. The outflow velocities and morphologies are consistent with being dominated by intermediate inclination angles (80 deg > i > 20 deg). This confirms the interpretation of the very red 24 micron to 70 micron colors of the PBRS as a signpost of high envelope densities, with only one (possibly two) cases of the red colors resulting from edge-on inclinations. We detect high-J (J_up > 13) CO lines and/or H_2O lines from 5 of 8 PBRS and only for those with detected CO outflows. The far-infrared CO rotation temperatures of the detected PBRS are marginally colder (~230 K) than those observed for most protostars (~300 K), and only one of these 5 PBRS has detected [OI] 63 micron emission. The high envelope densities could be obscuring some [OI] emission and cause a ~20 K reduction to the CO rotation temperatures.

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John J. Tobin, Amelia M. Stutz, P. Manoj, S. Thomas Megeath, Agata Karska, Zsofia Nagy, Friedrich Wyrowski, William Fischer, Dan M. Watson, Thomas Stanke. 2016-07-04. Characterizing the Youngest Herschel-detected Protostars II. Molecular Outflows from the Millimeter and the Far-infrared. https://doi.org/10.3847/0004-637x/831/1/36

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