The core population and kinematics of a massive clump at early stages: an ALMA view. (arXiv:2208.01675v1 [astro-ph.GA])

The core population and kinematics of a massive clump at early stages: an ALMA view. (arXiv:2208.01675v1 [astro-ph.GA])
<a href="http://arxiv.org/find/astro-ph/1/au:+Redaelli_E/0/1/0/all/0/1">E. Redaelli</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bovino_S/0/1/0/all/0/1">S. Bovino</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Sanhueza_P/0/1/0/all/0/1">P. Sanhueza</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Morii_K/0/1/0/all/0/1">K. Morii</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Sabatini_G/0/1/0/all/0/1">G. Sabatini</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Caselli_P/0/1/0/all/0/1">P. Caselli</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Giannetti_A/0/1/0/all/0/1">A. Giannetti</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Li_S/0/1/0/all/0/1">S. Li</a>

High-mass star formation theories make distinct predictions on the properties
of the prestellar seeds of high-mass stars. Observations of the early stages of
high-mass star formation can provide crucial constraints, but they are
challenging and scarce. We investigate the properties of the prestellar core
population embedded in the high-mass clump AGAL014.492-00.139, and we study the
kinematics at the clump and the clump-to-core scales. We have analysed an
extensive dataset acquired with the ALMA interferometer. Applying a dendrogram
analysis to the Band o-$rm H_2D^+$ data, we identified 22 cores. We have
fitted their average spectra in local-thermodinamic-equilibrium conditions, and
we analysed their continuum emission at $0.8 , rm mm$. The cores have
transonic to mildly supersonic turbulence levels and appear mostly low-mass,
with $M_mathrm{core}< 30 , rm M_odot$. Furthermore, we have analysed Band 3
observations of the $rm N_2H^+$ (1-0) transition, which traces the large scale
gas kinematics. Using a friend-of-friend algorithm, we identify four main
velocity coherent structures, all of which are associated with prestellar and
protostellar cores. One of them presents a filament-like structure, and our
observations could be consistent with mass accretion towards one of the
protostars. In this case, we estimate a mass accretion rate of $
dot{M}_mathrm{acc}approx 2 times 10^{-4} rm , M_odot , yr^{-1}$. Our
results support a clump-fed accretion scenario in the targeted source. The
cores in prestellar stage are essentially low-mass, and they appear subvirial
and gravitationally bound, unless further support is available for instance due
to magnetic fields.

High-mass star formation theories make distinct predictions on the properties
of the prestellar seeds of high-mass stars. Observations of the early stages of
high-mass star formation can provide crucial constraints, but they are
challenging and scarce. We investigate the properties of the prestellar core
population embedded in the high-mass clump AGAL014.492-00.139, and we study the
kinematics at the clump and the clump-to-core scales. We have analysed an
extensive dataset acquired with the ALMA interferometer. Applying a dendrogram
analysis to the Band o-$rm H_2D^+$ data, we identified 22 cores. We have
fitted their average spectra in local-thermodinamic-equilibrium conditions, and
we analysed their continuum emission at $0.8 , rm mm$. The cores have
transonic to mildly supersonic turbulence levels and appear mostly low-mass,
with $M_mathrm{core}< 30 , rm M_odot$. Furthermore, we have analysed Band 3
observations of the $rm N_2H^+$ (1-0) transition, which traces the large scale
gas kinematics. Using a friend-of-friend algorithm, we identify four main
velocity coherent structures, all of which are associated with prestellar and
protostellar cores. One of them presents a filament-like structure, and our
observations could be consistent with mass accretion towards one of the
protostars. In this case, we estimate a mass accretion rate of $
dot{M}_mathrm{acc}approx 2 times 10^{-4} rm , M_odot , yr^{-1}$. Our
results support a clump-fed accretion scenario in the targeted source. The
cores in prestellar stage are essentially low-mass, and they appear subvirial
and gravitationally bound, unless further support is available for instance due
to magnetic fields.

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