J/AJ/166/183 High-mass YSOs between 350 and 4000pc (Vioque+, 2023)
Clustering properties of intermediate and high-mass Young Stellar Objects.
Vioque M., Cavieres M., Pantaleoni Gonzalez M., Ribas A., Oudmaijer R.D.,
Mendigutia I., Kilian L., Canovas H., Kuhn M.A.
<Astron. J. 166, 183 (2023)>
=2023AJ....166..183V 2023AJ....166..183V (SIMBAD/NED BibCode)
ADC_Keywords: YSOs ; Associations, stellar ; Optical
Keywords: Star formation - Clustering - Young star clusters - Star clusters -
Young stellar objects - Herbig Ae/Be stars - Massive stars -
T Tauri stars - Emission line stars - Protoplanetary disks
Abstract:
We have selected 337 intermediate- and high-mass young stellar objects
(YSOs; 1.5-20M☉) well-characterized with spectroscopy. By means
of the clustering algorithm HDBSCAN, we study their clustering and
association properties in the Gaia DR3 catalog as a function of
stellar mass. We find that the lower-mass YSOs (1.5-4M☉) have
clustering rates of 55%-60% in Gaia astrometric space, a percentage
similar to that found in the T Tauri regime. However,
intermediate-mass YSOs in the range 4-10M☉ show a decreasing
clustering rate with stellar mass, down to 27%. We find tentative
evidence suggesting that massive YSOs (>10M☉) often (yet not
always) appear clustered. We put forward the idea that most massive
YSOs form via a mechanism that demands many low-mass stars around
them. However, intermediate-mass YSOs form in a classical
core-collapse T Tauri way, yet they do not appear often in the
clusters around massive YSOs. We also find that intermediate- and
high-mass YSOs become less clustered with decreasing disk emission and
accretion rate. This points toward an evolution with time. For those
sources that appear clustered, no major correlation is found between
their stellar properties and the cluster sizes, number of cluster
members, cluster densities, or distance to cluster centers. In doing
this analysis, we report the identification of 55 new clusters. We
tabulated all of the derived cluster parameters for the considered
intermediate- and high-mass YSOs.
Description:
This study constitutes the first large-scale analysis of the
clustering properties of intermediate- and high-mass YSOs
(1.5-20M☉), encompassing the classical groups of Herbig Ae/Be
stars, MYSOs, and intermediate-mass T Tauris. We applied an HDBSCAN
clustering methodology to 337 spectroscopically characterized
intermediate- and high-mass YSOs with Gaia data. We analyzed the
clustering properties of the 263 stars located in the distance range
where our methodology works best (350-4000pc). We present the
resulting cluster parameters for these sources in Table 1.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 221 263 Clustering properties of the 263 intermediate and
high-mass YSOs analysed between 350 and 4000pc
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See also:
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 28 A28 --- Name Main SIMBAD identifier
30- 48 I19 --- GaiaDR3 Gaia DR3 identifier
50- 53 F4.2 --- 5D-30-30 HDBSCAN cluster probability in 5d astrometric
space with 'min_samples'=30 and
'minclustersize'=30
55- 58 F4.2 --- 3D-30-30 HDBSCAN cluster probability in 3d astrometric
space with 'min_samples'=30 and
'minclustersize'=30
60- 63 F4.2 --- 5D-10-10 HDBSCAN cluster probability in 5d astrometric
space with 'min_samples'=10 and
'minclustersize'=10
65- 68 F4.2 --- 3D-10-10 HDBSCAN cluster probability in 3d astrometric
space with 'min_samples'=10 and
'minclustersize'=10
70- 89 F20.16 deg RAdeg Right Ascension in decimal degrees
(ICRS) at Ep=2016
91- 92 I2 h RAh Right Ascension (ICRS) at Ep=2016
94- 95 I2 min RAm Right Ascension (ICRS) at Ep=2016
97- 98 I2 s RAs Right Ascension (ICRS) at Ep=2016
100-120 F21.17 deg DEdeg Declination in decimal degrees
(ICRS) at Ep=2016
122 A1 --- DE- Declination sign (ICRS) at Ep=2016
123-124 I2 deg DEd Declination (ICRS) at Ep=2016
126-127 I2 arcmin DEm Declination (ICRS) at Ep=2016
129-132 F4.1 arcsec DEs Declination (ICRS) at Ep=2016
134-138 F5.2 mag Gmag Gaia DR3 mean G band magnitude
140-146 F7.2 pc Dist Distance to source
148-154 F7.2 pc E_Dist Upper uncertainty in Dist
156-161 F6.2 pc e_Dist Lower uncertainty in Dist
163-167 F5.2 Msun Mass ? Stellar mass
169-173 F5.2 Msun E_Mass ? Upper uncertainty in Mass
175-178 F4.2 Msun e_Mass ? Lower uncertainty in Mass
180-183 I4 --- Num ? Number of cluster members
185-189 F5.2 pc R80 ? Radius containing 80% of cluster's stars
191-196 F6.2 pc-2 CDen ? Density of stars per pc2
198-202 F5.2 pc DCenter ? Distance to cluster center
204-211 A8 --- HDBSCAN HDBSCAN configuration that yielded cluster
identification, or isolated stars
213-221 A9 --- Note Additional notes (1)
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Note (1): Notes as follows:
new = new cluster identification
cont = possible cluster miss-identification
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Acknowledgements:
Miguel Vioque, miguel.vioque(at)alma.cl
(End) Prepared by [AAS], Patricia Vannier [CDS] 11-Oct-2023