The outflow in the L1157 dark cloud - Evidence for shock heating of the interacting gas

Abstract

view Abstract Citations (95) References (19) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Outflow in the L1157 Dark Cloud: Evidence for Shock Heating of the Interacting Gas Umemoto, T. ; Iwata, T. ; Fukui, Y. ; Mikami, H. ; Yamamoto, S. ; Kameya, O. ; Hirano, N. Abstract In the L1157 dark cloud, a well-collimated bipolar CO outflow associated with a cold IRAS source 20386 + 6751 was discovered. The gas temperature toward the blue lobe of the outflow rises to about 30 K from the temperature of the surrounding gas (not greater than 10 K); this high temperature region is very localized within the blue lobe. The HCO(+), HCN, and NH3 lines show blueshifted and broad-line profiles toward the blue CO lobe. Furthermore, their distributions are similar to that of the blue lobe. Analysis of the energy of the outflow and dense gas suggests that a strong shock caused by the outflow is responsible for the temperature enhancement. Such shock heating has rarely been observed in low-mass star-forming regions. These data show that the outflow has an influence on the thermal properties of the parent cloud at least locally through shock processes in its early evolutionary stage. Publication: The Astrophysical Journal Pub Date: June 1992 DOI: 10.1086/186431 Bibcode: 1992ApJ...392L..83U Keywords: Gas Flow; Infrared Astronomy Satellite; Interstellar Matter; Shock Wave Interaction; Star Formation; Stellar Composition; Ammonia; Carbon Monoxide; Formyl Ions; Hydrocyanic Acid; Shock Heating; Astrophysics; ISM: MOLECULES; ISM: INDIVIDUAL ALPHANUMERIC: L1157; ISM: JETS AND OUTFLOWS; STARS: FORMATION; SHOCK WAVES full text sources ADS | data products SIMBAD (2)