J/A+A/690/A185 Dynamical accretion flows (Wells+, 2024)
Dynamical accretion flows.
ALMAGAL: Flows along filamentary structures in high-mass star-forming clusters.
Wells M.R.A., Beuther H., Molinari S., Schilke P., Battersby C., Ho P.,
Sanchez-Monge A., Jones B., Scheuck M.B., Syed J., Gieser C., Kuiper R.,
Elia D., Coletta A., Traficante A., Wallace J., Rigby A.J., Klessen R.S.,
Zhang Q., Walch S., Beltran M.T., Tang Y., Fuller G.A., Lis D.C.,
Moeller T., van der Tak F., Klaassen P.D., Clarke S.D., Moscadelli L.,
Mininni C., Zinnecker H., Maruccia Y., Pezzuto S., Benedettini M.,
Soler J.D., Brogan C.L., Avison A., Sanhueza P., Schisano E., Liu T.,
Fontani F., Rygl K.L.J., Wyrowski F., Bally J., Walker D.L., Ahmadi A.,
Koch P., Merello M., Law C.Y., Testi L.
<Astron. Astrophys. 690, A185 (2024)>
=2024A&A...690A.185W 2024A&A...690A.185W (SIMBAD/NED BibCode)
ADC_Keywords: Stars, radio ; Interstellar medium ; Accretion
Keywords: stars: kinematics and dynamics - ISM: jets and outflows -
stars: formation - submillimeter: stars
Abstract:
Investigating the flow of material along filamentary structures
towards the central core can help provide insights into high-mass star
formation and evolution.
Our main motivation is to answer the question of what the properties
of accretion flows are in star-forming clusters. We used data from the
ALMA Evolutionary Study of High Mass Protocluster Formation in the
Galaxy (ALMAGAL) survey to study 100 ALMAGAL regions at a ∼1"
resolution, located between ∼2 and 6kpc.
Making use of the ALMAGAL ∼1.3mm line and continuum data, we
estimated flow rates onto individual cores. We focus specifically on
flowrates along filamentary structures associated with these cores.
Our primary analysis is centered around position velocity cuts in
H2CO (30,3-20,2), which allow us to measure the velocity fields
surrounding these cores. Combining this work with column density
estimates, we were able to derive the flow rates along the extended
filamentary structures associated with cores in these regions.
Results. We selected a sample of 100 ALMAGAL regions, covering four
evolutionary stages from quiescent to protostellar, young stellar
objects (YSOs), and Hii regions (25 each). Using a dendrogram and line
analysis, we identify a final sample of 182 cores in 87 regions. In
this paper, we present 728 flow rates for our sample (4 per core),
analysed in the context of evolutionary stage, distance from the core,
and core mass. On average, for the whole sample, we derived flow rates
on the order of ∼10-4M/yr with estimated uncertainties of
±50%. We see increasing differences in the values among evolutionary
stages, most notably between the less evolved (quiescent and
protostellar) and more evolved (YSO and HII region) sources and we
also see an increasing trend as we move further away from the centre
of these cores. We also find a clear relationship between the
calculated flow rates and core masses ∼M2/3, which is in line with
the result expected from the tidal- lobe accretion mechanism. The
significance of these relationships is tested with Kolmogorov-Smirnov
and Mann Whitney U tests.
Overall, we see an increasing trend in the relationships between the
flow rate and the three investigated parameters, namely: evolutionary
stage, distance from the core, and core mass.
Description:
We tabulate coordinates and basic parameters of our 87 ALMAGAL sources
used in this work, along with their stellar classifications. In the
second table we list the offset positions of each core in each source,
the four flowrates associated with each core and a core mass estimate
from the astrodendro programme.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tabled1.dat 79 87 Source parameters
tabled2.dat 58 182 Core parameters
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Byte-by-byte Description of file: tabled1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 17 A17 --- ALMAGAL Source name in ALMAGAL catalogue
(AGLLL.llll+B.bbbb)
19- 24 I6 --- ID Internal source name
26- 32 F7.3 deg GLON Galactic longitude
34- 39 F6.3 deg GLAT Galactic latitude
41- 46 F6.1 km/s VLSR ALMAGAL LSR velocity
48- 51 I4 pc Dist ALMAGAL Distance
53- 56 I4 Msun Mass ALMAGAL Mass
58- 63 I6 Lsun Lum ALMAGAL Luminosity
65- 66 I2 K ModelTemp Temperature estimate
68- 79 A12 --- Class Stellar classification
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Byte-by-byte Description of file: tabled2.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- ID Internal source name
8- 13 F6.2 arcsec Xoffset Core offset from source central
position (x)
15- 20 F6.2 arcsec Yoffset Core offset from source central
position (y)
22- 27 F6.3 10-4Msun/yr FlowRateLout Outer left flowrate
29- 34 F6.3 10-4Msun/yr FlowRateLin Inner left flowrate
36- 41 F6.3 10-4Msun/yr FlowRateRin Inner right flowrate
43- 48 F6.3 10-4Msun/yr FlowRateRout Outer right flowrate
50- 56 F7.3 Msun Masscore Core mass estimate
58 I1 --- Idx [0/7] Astrodendro core ID number
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Acknowledgements:
Molly Wells, wells(at)mpia.de
(End) Patricia Vannier [CDS] 30-Aug-2024