Warm gas in protostellar outflows. II. EHV jet and outflows from OMC-2/3

Abstract

OMC-2/3 is one of the nearest embedded cluster-forming region that includes intermediate-mass protostars at early stages of evolution. A previous CO (3--2) mapping survey towards this region revealed outflow activity related to sources at different evolutionary phases. The present work aims to study the warm gas in the high-velocity emission from several outflows found in CO (3--2) emission by previous observations, determine their physical conditions, and make comparison with previous results in low-mass star-forming regions. We use the CHAMP+ heterodyne array on the APEX telescope to map the CO (6--5) and CO (7--6) emission in the OMC-2 FIR 6 and OMC-3 MMS 1-6 regions, and to observe ${}^{13}$CO (6--5) at selected positions. We analyze these data together with previous CO (3--2) observations. In addition, we mapped the SiO (5--4) emission in OMC-2 FIR 6. The CO (6--5) emission was detected in most of the outflow lobes in the mapped regions, while the CO (7--6) was found mostly from the OMC-3 outflows. In the OMC-3 MMS 5 outflow, a previously undetected extremely high velocity gas was found in CO (6--5). This extremely high velocity emission arises from the regions close to the central object MMS 5. Radiative transfer models revealed that the high-velocity gas from MMS 5 outflow consists of gas with $n_{{\mathrm{H}}_2}=$10${}^4$--10${}^5$ cm${}^{-3}$ and $T>$ 200 K, similar to what is observed in young Class 0 low-mass protostars. For the other outflows, values of $n_{{\mathrm{H}}_2}>$10${}^4$ cm${}^{-3}$ were found. The physical conditions and kinematic properties of the young intermediate-mass outflows presented here are similar to those found in outflows from Class 0 low-mass objects. Due to their excitation requirements, mid$-J$ CO lines are good tracers of extremely high velocity gas in young outflows likely related to jets.

Accepted for publication in Astronomy & Astrophysics

References in corpus (9)

• The APOGEE-2 Survey of the Orion Star Forming Complex II: Six-dimensional structure
• APEX-CHAMP+ high-J CO observations of low-mass young stellar objects: IV. Mechanical and radiative feedback
• Millimeter- and Submillimeter-Wave Observations of the OMC-2/3 Region. III. An Extensive Survey for Molecular Outflows
• Silicon Monoxide Observations Reveal a Cluster of Hidden Compact Outflows in the OMC1 South Region
• A Very Compact Extremely High Velocity Flow toward MMS 5 / OMC-3 Revealed with ALMA
• On the nature of outflows in intermediate-mass protostars: a case study of IRAS 20050+2720
• Millimeter- and Submillimeter-Wave Observations of the OMC-2/3 Region; I. Dispersing and Rotating Core around an Intermediate-mass Protostar MMS 7
• First measurement of the 14N/15N ratio in the analogue of the Sun progenitor OMC-2 FIR4
• Protostellar clusters in intermediate-mass (IM) star forming regions

Cited by in corpus (4)

• Illuminating a tadpole's metamorphosis II: observing the on-going transformation with ALMA
• Mid-$J$ CO Line Observations of Protostellar Outflows in the Orion Molecular Clouds
• Protostellar Outflows: a window to the past
• The chemical nature of Orion protostars: Are ORANGES different from PEACHES? ORANGES II