Temperature structure and kinematics of the IRDC G035.39-00.33

Abstract

Aims. Infrared dark clouds represent the earliest stages of high-mass star formation. Detailed observations of their physical conditions on all physical scales are required to improve our understanding of their role in fueling star formation. Methods. We investigate the large-scale structure of the IRDC G035.39-00.33, probing the dense gas with the classical ammonia thermometer. This allows us to put reliable constraints on the temperature of the extended, pc-scale dense gas reservoir and to probe the magnitude of its non-thermal motions. Available far-infrared observations can be used in tandem with the observed ammonia emission to estimate the total gas mass contained in G035.39-00.33. Results. We identify a main velocity component as a prominent filament, manifested as an ammonia emission intensity ridge spanning more than 6 pc, consistent with the previous studies on the Northern part of the cloud. A number of additional line-of-sight components are found, and a large scale, linear velocity gradient of ~0.2 km s${}^{-1}$ pc${}^{-1}$ is found along the ridge of the IRDC. In contrast to the dust temperature map, an ammonia-derived kinetic temperature map, presented for the entirety of the cloud, reveals local temperature enhancements towards the massive protostellar cores. We show that without properly accounting for the line of sight contamination, the dust temperature is 2-3 K larger than the gas temperature measured with NH${}_3$. Conclusions. While both the large scale kinematics and temperature structure are consistent with that of starless dark filaments, the kinetic gas temperature profile on smaller scales is suggestive of tracing the heating mechanism coincident with the locations of massive protostellar cores.

11 pages, 10 figures, accepted to A&A

References in corpus (17)

• Theory of Star Formation
• Infrared Emission from Interstellar Dust. IV. The Silicate-Graphite-PAH Model in the Post-Spitzer Era
• MAMBO Mapping of Spitzer c2d Small Clouds and Cores
• Observing the gas temperature drop in the high-density nucleus of L 1544
• An Ammonia Spectral Atlas of Dense Cores in Perseus
• Herschel-Planck dust optical-depth and column-density maps: I. Method description and results for Orion
• Fragmentation of Molecular Clumps and Formation of Protocluster
• Chains of dense cores in the Taurus L1495/B213 complex
• Large-scale filaments associated with Milky Way spiral arms
• The dynamical properties of dense filaments in the infrared dark cloud G035.39-00.33
• Complex, Quiescent Kinematics in a Highly Filamentary Infrared Dark Cloud
• Understanding star formation in molecular clouds II. Signatures of gravitational collapse of IRDCs
• A Census of Large-Scale ($\ge$ 10 pc), Velocity-Coherent, Dense Filaments in the Northern Galactic Plane: Automated Identification Using Minimum Spanning Tree
• Investigating the structure and fragmentation of a highly filamentary IRDC
• Unveiling the Early-Stage Anatomy of a Protocluster Hub with ALMA
• The fragmentation and stability of hierarchical structure in Serpens South
• Some like it cold: molecular emission and effective dust temperatures of dense cores in the Pipe Nebula

Cited by in corpus (19)

• Filamentary Accretion Flows in the Infrared Dark Cloud G14.225-0.506 Revealed by ALMA
• ALMA-IRDC: Dense gas mass distribution from cloud to core scales
• Similar complex kinematics within two massive, filamentary infrared dark clouds
• Physical and chemical structure of the Serpens filament -- fast formation and gravity-driven accretion
• Multicomponent kinematics in a massive filamentary IRDC
• Large-scale Velocity-coherent Filaments in the SEDIGISM Survey: Association with Spiral Arms and Fraction of Dense Gas
• Probing the massive star forming environment - a multiwavelength investigation of the filamentary IRDC G333.73+0.37
• Ammonia observations towards the Aquila Rift cloud complex
• Hunting pre-stellar cores with APEX: IRAS16293E (Oph464)
• ALMA-IRDC II. First high-angular resolution measurements of the 14N/15N ratio in a large sample of infrared-dark cloud cores
• Cosmic-ray ionisation rate in low-mass cores: the role of the environment
• A Comprehensive Study of the Young Cluster IRAS 05100+3723: Properties, Surrounding Interstellar Matter, and Associated Star Formation
• Synthetic ngVLA line observations of a massive star-forming cloud
• An X-ray View of Two Infrared Dark Clouds G034.43+00.24 and G035.39-00.33
• KAgoshima Galactic Object survey with Nobeyama 45-metre telescope by Mapping in Ammonia lines (KAGONMA): Discovery of parsec-scale CO depletion in the Canis Major star-forming region
• Sub-kpc scale gas density histogram of the Galactic molecular gas: a new statistical method to characterise galactic-scale gas structures
• Low-velocity large-scale shocks in the infrared dark cloud G035.39-00.33: bubble-driven cloud-cloud collisions
• The TMRT K Band Observations towards 26 Infrared Dark Clouds: NH${}_3$, CCS, and HC${}_3$N
• SiO emission in the filamentary Infrared Dark Cloud G035.39-00.33: An ALMA view