view Abstract Citations (62) References (39) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Extremely High-Velocity Molecular Flows in Young Stellar Objects Koo, Bon-Chul Abstract Very sensitive, wideband CO J = 1-0, J = 2-1, and HCO+ J = 1-0 spectra of several young stellar objects are presented. Extremely weak and very broad extremely high velocity (EHV) wings are found in GL 4909, HH 7-11, S140, and MWC 1080. The line profiles of EHV wings are smooth or flat, quite different from steep HV wings. In L551 and HL Tau, EHV wings as broad as other sources are not found, which would be due to the inclination of the bipolar flows to the line of sight. From the excitation temperature of about 10 K derived for the EHV flows, the estimated column density of CO yields a number density too small to explain the observed ratio of CO J = 2-1 to J = 1-0 intensity. It is concluded that either EHV flows are composed of small dense clumps or most of the carbon in the flow is atomic carbon, unless the kinetic temperature of the flow is much higher than 100 K. Publication: The Astrophysical Journal Pub Date: February 1989 DOI: 10.1086/167105 Bibcode: 1989ApJ...337..318K Keywords: Molecular Flow; Pre-Main Sequence Stars; Stellar Spectra; Stellar Winds; Carbon Monoxide; Formyl Ions; Line Spectra; Molecular Spectra; Astrophysics; INTERSTELLAR: MOLECULES; LINE PROFILES; STARS: PRE--MAIN-SEQUENCE; STARS: WINDS full text sources ADS | data products SIMBAD (11)