J/AN/329/801 Agglomerate of early-type Hipparcos stars (Caballero+, 2008)
A revisit to agglomerate of early-type Hipparcos stars.
Caballero J.A., Dinis L.
<Astron. Nachrichten, 329, 801-834 (2008)>
=2008AN....329..801C 2008AN....329..801C
ADC_Keywords: Associations, stellar ; Stars, early-type ; Proper motions
Keywords: stars: early-type - open clusters and associations: general -
open clusters and associations: individual (Ori OB1b, P Puppis) -
methods: data analysis - astronomical data bases: miscellaneous
Abstract:
We study the spatial structure and sub-structure of regions rich in
Hipparcos stars with blue BT-VT colours. These regions, which
comprise large stellar complexes, OB associations, and young open
clusters, are tracers of on-going star formation in the Galaxy. The
DBSCAN (Density-Based Spatial Clustering of Applications with Noise)
data clustering algorithm is used to look for spatial overdensities of
early-type stars. Once an overdensity, "agglomerate", is identified,
we carry out a data and bibliographic compilation of their star member
candidates. The actual membership in agglomerate of each early-type
star is studied based on its heliocentric distance, proper motion, and
previous spectro-photometric information. We identify 35 agglomerates
of early-type Hipparcos stars. Most of them are associated to
previously known clusters and OB associations. The previously unknown
P Puppis agglomerate is subject of a dedicated study with Virtual
Observatory tools.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 109 35 Agglomerates of early-type Hipparcos stars
tablea1.dat 105 406 Early-type Hipparcos stars in aggregates
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See also:
I/239 : The Hipparcos and Tycho Catalogues (ESA 1997)
I/311 : Hipparcos, the New Reduction (van Leeuwen, 2007)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- --- Escorial
10- 11 I2 --- Escorial Agglomerate designation (Escorial NN)
13- 25 A13 ---- Star Reference star
27- 31 F5.1 deg GLON Galactic longitude
33- 37 F5.1 deg GLAT Galactic latitude
39- 45 A7 --- Sup-Aggl Super-Agglomerate designation
47- 72 A26 --- Assoc Cluster/Association/Complex/Region
74- 75 I2 --- Nstar Number of star in the agglomerate
77-109 A33 --- Cont Possible contaminant(s)
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- --- Escorial
10- 11 I2 --- Escorial Agglomerate designation (Escorial NN)
13- 18 I6 --- HIP HIP number
20- 33 A14 --- Name Other name
35- 45 A11 --- SpType MK spectral type
47- 50 I4 pc Dist ?=- Heliocentric distance
52- 54 I3 pc e_Dist ?=- rms uncertainty on Dist
55 A1 --- n_Dist [:h] Note on Dist (1)
57- 58 I2 h RAh Right ascension (J2000)
60- 61 I2 min RAm Right ascension (J2000)
63- 67 F5.2 s RAs Right ascension (J2000)
69 A1 --- DE- Declination sign (J2000)
70- 71 I2 deg DEd Declination (J2000)
73- 74 I2 arcmin DEm Declination (J2000)
76- 79 F4.1 arcsec DEs Declination (J2000)
81- 86 F6.2 mas/yr pmRA ?=- Proper motion along RA, pmRA*cosDE
88- 91 F4.2 mas/yr e_pmRA ?=- rms uncertainty on pmRA
92 A1 --- n_pmRA [)] Difference in pmRA (2)
94- 99 F6.2 mas/yr pmDE ?=- Proper motion along DE
101-104 F4.2 mas/yr e_pmDE ?=- rms uncertainty on pmDE
105 A1 --- n_pmDE [)] Difference in pmDE (2)
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Note (1): Note as follows:
: = proper motion with very large error bars and improbable distance
h = distance from original HIP (I/239) reduction with lower error
bars (only in these particular cases) than in van Leeuwen
(2007, Cat. I/311) HIP new reduction.
Note (2): Proper motions differs from those of van Leeuwen (2007, Cat.
I/311) HIP new reduction
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 16-Jan-2009