{'fraction_non_alphanumeric': 0.047107014848950336, 'fraction_numerical': 0.029697900665642603, 'mean_word_length': 4.309782608695652, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 2, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Warm gas in protostellar outﬂows II. Extremely high-velocity emission jet and outﬂows from OMC-2/3 (cid:63)

Context. OMC-2/3 is one of the nearest embedded cluster-forming regions 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. Aims. The present work presents a study of the warm gas in the high-velocity emission from several outﬂows found in CO (3–2) emission by previous observations, determines their physical conditions, and makes a comparison with previous results in low-mass star-forming regions. Methods. We used 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 analyzed these data together with previous CO (3–2) observations. In addition, we mapped the SiO (5–4) emission in OMC-2 FIR 6. Results. 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 in 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 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 H 2 > 10 4 cm − 3 were found. Conclusions. 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.