Spectral-Line Survey at Millimeter and Submillimeter Wavelengths toward an Outflow-Shocked Region, OMC 2-FIR 4

Abstract

We performed the first spectral-line survey at 82--106 GHz and 335--355 GHz toward the outflow-shocked region, OMC 2-FIR 4, the outflow driving source, FIR 3, and the northern outflow lobe, FIR 3N. We detected 120 lines of 20 molecular species. The line profiles are found to be classifiable into two types: one is a single Gaussian component with a narrow ($<$ 3 km s${}^{-1}$) width and another is two Gaussian components with narrow and wide ($>$ 3km s${}^{-1}$) widths. The narrow components for the most of the lines are detected at all positions, suggesting that they trace the ambient dense gas. For CO, CS, HCN, and HCO${}^{+}$, the wide components are detected at all positions, suggesting the outflow origin. The wide components of C${}^{34}$S, SO, SiO, H${}^{13}$CN, HC${}^{15}$N, H${}_2^{13}$CO, H${}_2$CS, HC${}_3$N, and CH${}_3$OH are detected only at FIR 4, suggesting the outflow-shocked gas origin. The rotation diagram analysis revealed that the narrow components of C${}_2$H and H${}^{13}$CO${}^{+}$ show low temperatures of 12.5$\pm$1.4 K, while the wide components show high temperatures of 20--70 K. This supports our interpretation that the wide components trace the outflow and/or outflow-shocked gas. We compared observed molecular abundances relative to H${}^{13}$CO${}^{+}$ with those of the outflow-shocked region, L1157 B1, and the hot corino, IRAS 16293-2422. Although we cannot exclude a possibility that the chemical enrichment in FIR 4 is caused by the hot core chemistry, the chemical compositions in FIR 4 are more similar to those in L1157 B1 than those in IRAS 16293-2422.

ApJS accepted for publication

References in corpus (9)

• The distance to the Orion Nebula
• A Parallactic Distance of 389 +24/-21 parsecs to the Orion Nebula Cluster from Very Long Baseline Array Observations
• Massive Quiescent Cores in Orion: Dynamical State Revealed by High-Resolution Ammonia Maps
• Millimeter- and Submillimeter-Wave Observations of the OMC-2/3 Region. III. An Extensive Survey for Molecular Outflows
• Millimeter- and Submillimeter-Wave Observations of the OMC-2/3 Region. II. Observational Evidence for Outflow-Triggered Star Formation in the OMC-2 FIR 3/4 Region
• High angular resolution observations towards OMC-2 FIR 4: Dissecting an intermediate-mass protocluster
• Catalog of dense cores in the Orion A giant molecular cloud
• The Herschel/HIFI spectral survey of OMC-2 FIR 4 (CHESS): An overview of the 480 to 1902 GHz range
• Depletion of chlorine into HCl ice in a protostellar core

Cited by in corpus (21)

• Seeds Of Life In Space (SOLIS): The organic composition diversity at 300--1000 au scale in Solar-type star forming regions
• G11.92-0.61 MM1: A Keplerian disc around a massive young proto-O star
• Testing the universality of the star formation efficiency in dense molecular gas
• Resolving the fragmentation of high line-mass filaments with ALMA: the integral shaped filament in Orion A
• The CARMA-NRO Orion Survey
• SOLIS IV. Hydrocarbons in the OMC-2 FIR 4 region, a probe of energetic particle irradiation of the region
• Molecular filament formation and filament-cloud interaction: Hints from Nobeyama 45m telescope observations
• Survey Observations to Study Chemical Evolution from High-mass Starless Cores to High-mass Protostellar Objects I: HC3N and HC5N
• Dense gas in low-metallicity galaxies
• Nobeyama 45-m Mapping Observations toward Orion A.I. Molecular Outflows
• Probing the Physics of Star-Formation (ProPStar): II. The first systematic search for streamers toward protostars
• Chemical Diversity in Three Massive Young Stellar Objects associated with 6.7 GHz CH${}_3$OH Masers
• Clustered star formation at early evolutionary stages. Physical and chemical analysis of the young star-forming regions ISOSS J22478+6357 and ISOSS J23053+5953
• OMC-2 FIR 4 under the microscope: Shocks, filaments, and a highly collimated jet at 100 au scales
• A Census of Outflow to Magnetic Field Orientations in Nearby Molecular Clouds
• Nobeyama 45-m Mapping Observations toward Orion A. III. Multi-Line Observations toward an Outflow-shocked Region, OMC-2 FIR
• A Census of Protostellar Outflows in Nearby Molecular Clouds
• SOLIS XVII: Jet candidate unveiled in OMC-2 and its possible link to the enhanced cosmic-ray ionisation rate
• Atomic Carbon in the Central Molecular Zone of the Milky Way : Possible Cosmic-ray Induced Chemistry or Time-Dependent Chemistry Associated with SNR Sagittarius A East
• Unmasking the physical information inherent to interstellar spectral line profiles with Machine Learning. I. Application of LTE to HCN and HNC transitions
• Cluster Formation in GGD12-15: Infall Motion with Rotation of the Natal Clump