Properties of Contracting Massive Protostellar Cores

Abstract

Studies of the structure and kinematics of cores associated with the regions of massive star and star cluster formation are necessary for constructing scenario for the evolution of these objects. We analyzed spectral maps of the massive cores of G012.418+00.506, G326.472+00.888, G328.567--00.535, G335.586--00.289 and G343.127--00.063 from the MALT90 survey in the HCO${}^{+}$(1--0) and H${}^{13}$CO${}^{+}$(1--0) lines. The cores are at different stages of evolution and have signs of contraction. By fitting spectral maps calculated within the framework of a spherically symmetric model into the observed ones, the parameters of the radial profiles of density, turbulent velocity and contraction velocity were calculated. The power-law index of the density decay with distance from the center varies in the range of $\sim 1.5-2.8$. The lowest value is obtained for the core of G326.472+00.888 without internal sources. The contraction velocity in all cores depends weakly on the distance from the center, decreasing with an index of $\sim 0.1$, which differs from the free-fall mode. There are indications of rotation for the cores of G328.567--00.535 and G335.586--00.289. Analysis of ${}^{13}$CO(2--1) data from the SEDIGISM survey for the regions G012.418+00.506, G335.586--00.289, and G343.127--00.063 revealed motions from the surrounding gas toward the cores. The results obtained indicate that the massive cores under consideration interact with their environment and are apparently in a state of global collapse.t the massive cores under consideration interact with their environment and are apparently in a state of global collapse.

34 pages, 5 figures

References in corpus (56)

• The Formation of Massive Stars from Turbulent Cores
• SUMSS: A Wide-Field Radio Imaging Survey of the Southern Sky. II. The Source Catalogue
• ATLASGAL - The APEX Telescope Large Area Survey of the Galaxy at 870 microns
• Hi-GAL: the Herschel infrared Galactic Plane Survey
• Competitive accretion in embedded stellar cluster
• Physical Conditions in Regions of Star Formation
• High-Mass Star and Massive Cluster Formation in the Milky Way
• A Catalog of Extended Green Objects (EGOs) in the GLIMPSE Survey: A new sample of massive young stellar object outflow candidates
• Global Hierarchical Collapse In Molecular Clouds. Towards a Comprehensive Scenario
• The initial conditions of stellar protocluster formation. I. A catalogue of Spitzer dark clouds
• A CS J=5-4 Mapping Survey Towards High-mass Star Forming Cores Associated with Water Masers
• FOREST Unbiased Galactic plane Imaging survey with the Nobeyama 45-m telescope (FUGIN) I: Project Overview and Initial Results
• MALT90: The Millimetre Astronomy Legacy Team 90 GHz Survey
• The RMS Survey: 6 cm continuum VLA observations towards candidate massive YSOs in the northern hemisphere
• Far-Infrared Dust Temperatures and Column Densities of the MALT90 Molecular Clump Sample
• N2H+(1-0) survey of massive molecular cloud cores
• Gravitational collapse of the OMC-1 region
• Southern class I methanol masers at 36 and 44 GHz
• Precise Positions of Methanol Masers
• The Bolocam Galactic Plane Survey. XIV. Physical Properties of Massive Starless and Star Forming Clumps
• The SEDIGISM survey: first data release and overview of the Galactic structure
• A 95 GHz Class I Methanol Maser Survey Toward GLIMPSE Extended Green Objects (EGOs)
• Search for massive protostellar candidates in the southern hemisphere: I. Association with dense gas
• Accurate water maser positions from HOPS
• ATOMS: ALMA Three-millimeter Observations of Massive Star-forming regions -- XV. Steady Accretion from Global Collapse to Core Feeding in Massive Hub-filament System SDC335
• High Angular Resolution Observations of the Collimated Jet Source Associated with a Massive Protostar in IRAS 16547-4247
• A Search for Infall Evidence in EGOs I: the Northern Sample
• A Water Maser and Ammonia Survey of GLIMPSE Extended Green Objects (EGOs)
• Online Database of Class I Methanol Masers
• The ATLASGAL survey: The sample of young massive cluster progenitors
• An ALMA study of hub-filament systems I. On the clump mass concentration within the most massive cores
• A New 95 GHz Methanol Maser Catalog: I. Data
• Chemical differentiation in regions of high-mass star formation I. CS, dust and N2H^+ in southern sources
• Density Profiles in Molecular Cloud Cores Associated with High-Mass Star-Forming Regions
• An Asymmetric Keplerian Disk Surrounding the O-type Protostar IRAS16547$-$4247
• CB17: Inferring the dynamical history of a prestellar core with chemo-dynamical models
• Properties of massive star-forming clumps with infall motions
• High-resolution APEX/LAsMA ${}^{12}$CO and ${}^{13}$CO (3-2) observation of the G333 giant molecular cloud complex : I. Evidence for gravitational acceleration in hub-filament systems
• A Global View on Star Formation: The GLOSTAR Galactic Plane Survey V. 6.7 GHz Methanol Maser Catalogue
• Dynamical Accretion Flows -- ALMAGAL: Flows along filamentary structures in high-mass star-forming clusters
• ATOMS: ALMA Three-millimeter Observations of Massive Star-forming regions -- XII: Fragmentation and multi-scale gas kinematics in protoclusters G12.42+0.50 and G19.88-0.53
• LOC program for line radiative transfer
• Fragmentation and filaments at the onset of star and cluster formation: SABOCA 350 $\mu$m view of ATLASGAL selected massive clumps
• Accurate OH maser positions from the SPLASH pilot region
• The QUaD Galactic Plane Survey II: A Compact Source Catalog
• 84-GHz methanol masers, their relationship to 36-GHz methanol masers and their molecular environments
• Thermal structure of a protostellar envelope
• Initial phases of high-mass star formation: A multiwavelength study towards the extended green object G12.42+0.50
• Parkes full polarization spectra of OH masers - II. Galactic longitudes 240 to 350
• Determining the Parameters of Massive Protostellar Clouds via Radiative Transfer Modeling
• Inflow Motions associated with High-mass Protostellar Objects
• Principal component analysis for estimating parameters of the L1287 dense core by fitting model spectral maps into observed ones
• Chemical evolution of N2H+ in six massive star-forming regions
• Multi-frequency Studies of Massive Cores with Complex Spatial and Kinematic Structures
• Simulations of the isothermal collapse of magnetic rotating protostellar clouds
• Physical Properties and Kinematics of Dense Cores Associated with Regions of Massive Star Formation from the Southern Sky