J/A+A/651/A104 Spiral arms Gaia EDR3 (Poggio+, 2021)
Galactic spiral structure revealed by Gaia EDR3.
Poggio E., Drimmel R., Cantat-Gaudin T., Ramos P., Ripepi V., Zari E.,
Andrae R., Blomme R., Chemin L., Clementini G., Figueras F., Fouesneau M.,
Fremat Y., Lobel A., Marshall D.J., Muraveva T., Romero-Gomez M.
<Astron. Astrophys. 651, A104 (2021)>
=2021A&A...651A.104P 2021A&A...651A.104P (SIMBAD/NED BibCode)
ADC_Keywords: Milky Way ; Clusters, open ; Proper motions ;
Parallaxes, trigonometric
Keywords: Galaxy: disk - Galaxy: structure - Galaxy: stellar content
Abstract:
Using the astrometry and integrated photometry from the Gaia Early
Data Release 3 (EDR3), we map the density variations in the
distribution of young Upper Main Sequence (UMS) stars, open clusters
and classical Cepheids in the Galactic disk within several kiloparsecs
of the Sun. Maps of relative over/under-dense regions for UMS stars in
the Galactic disk are derived, using both bivariate kernel density
estimators and wavelet transformations. The resulting overdensity maps
exhibit large-scale arches, that extend in a clumpy but coherent way
over the entire sampled volume, indicating the location of the spiral
arms segments in the vicinity of the Sun. Peaks in the UMS overdensity
are well-matched by the distribution of young and intrinsically bright
open clusters. By applying a wavelet transformation to a sample of
classical Cepheids, we find that their overdensities possibly extend
the spiral arm segments on a larger scale (∼10kpc from the Sun).
While the resulting map based on the UMS sample is generally
consistent with previous models of the Sagittarius-Carina spiral arm,
the geometry of the arms in the III quadrant (galactic longitudes
180°<l<270°) differs significantly from many previous models.
In particular we find that our maps favour a larger pitch angle for
the Perseus arm, and that the Local Arm extends into the III quadrant
at least 4kpc past the Sun's position, giving it a total length of at
least 8kpc.
Description:
In this paper, we map the segments of the nearest spiral arms in the
Milky Way using young stellar populations. This catalog contains 1872
Open Clusters, of which 1851 have Gaia EDR3 astrometry.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
ocs_edr3.dat 138 1872 Catalog
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See also:
I/350 : Gaia EDR3 (Gaia Collaboration, 2020)
J/A+A/640/A1 : Portrait Galactic disc (Cantat-Gaudin+, 2020)
Byte-by-byte Description of file: ocs_edr3.dat
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Bytes Format Units Label Explanations
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1- 17 A17 --- Cluster Cluster name
19- 25 F7.3 deg RAdeg [] Mean right ascension of members (ICRS)
at Ep=2015.5
27- 33 F7.3 deg DEdeg Mean declination of members (ICRS)
at Ep=2015.5
35- 41 F7.3 deg GLON Mean Galactic longitude of members
43- 49 F7.3 deg GLAT Mean Galactic latitude of members
51- 56 F6.4 deg r50 Radius containing half the members
58- 61 F4.2 [yr] agenn ? Age (logt) of the cluster (from
Cantat-gaudin et al., 2020A&A...640A...1C 2020A&A...640A...1C)
63- 67 F5.2 mag dmnn ? Distance modulus of the cluster (from
Cantat-gaudin et al., 2020A&A...640A...1C 2020A&A...640A...1C)
69- 75 F7.1 pc distpc ? Distance in parsecs
(converted distance modulus)
77- 84 F8.4 mas/yr pmRA* ? Median proper motion along RA of members,
pmRA*cosDE
86- 91 F6.4 mas/yr e_pmRA* ? Sigma=1.4826*MAD where MAD is the median
absolute deviation of pmRA*
93-100 F8.4 mas/yr pmDE ? Median proper motion along DE of members
102-107 F6.4 mas/yr e_pmDE ? Sigma=1.4826*MAD where MAD is the median
absolute deviation of pmRDE
109-113 F5.3 mas plx ? Median parallax of members
115-120 F6.4 mas e_plx ? Sigma=1.4826*MAD where MAD is the median
absolute deviation of plc
122-125 I4 --- nb Number of members
127-129 I3 --- nbB0 Number of members brighter than
absolute magnitude 0 in the G band
131-133 I3 --- nbB2 Number of members brighter than
absolute magnitude 2 in the G band
135-138 I4 --- nbB4 Number of members brighter than
absolute magnitude 4 in the G band
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Acknowledgements:
Eloisa Poggio, poggio.eloisa(at)gmail.com
(End) Patricia Vannier [CDS] 17-May-2021