J/A+A/593/A116 Open clusters within 1.8 kpc of the Sun (Joshi+, 2016)
Study of open clusters within 1.8 kpc and understanding the Galactic structure.
Joshi Y.C., Dambis A.K., Pandey A.K., Joshi S.
<Astron. Astrophys. 593, A116 (2016)>
=2016A&A...593A.116J 2016A&A...593A.116J (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; Radial velocities ; Proper motions ; Milky Way
Keywords: methods: statistical - methods: data analysis -
open clusters and associations: general - Galaxy: structure
Abstract:
Based on an almost complete sample of Galactic open star clusters
within 1.8kpc, we perform a comprehensive statistical analysis of
various cluster parameters like spatial position, age, size, mass and
extinction in order to understand the general properties of the open
cluster system in the Galaxy and the Galactic structure. Based on the
distribution of 1241 open clusters about the Galactic plane and in
different age bins, we find the average Galactic scale height as
Zh=60±2pc for the youngest cluster population having Age<700Myr,
however, it increases up to 64±2pc when we also include older
population of clusters. The solar offset is found to be 6.2±1.1pc
above the formal Galactic plane. We derive a local mass density of
ρ0=0.090±0.005M☉/pc3 and found a negligibly small
amount of dark matter in the solar neighbourhood. The reddening in the
direction of clusters suggests a strong correlation with their
vertical distance from the Galactic plane having a respective slope of
dE(B-V)/dz=0.40±0.04 and 0.42±0.05 mag/kpc below and above the GP.
We observe a linear mass-radius and mass-age relations in the open
clusters and derive a slope of dR/d(logM)=2.08±0.10 and
d(logM)/d(logT)=-0.36±0.05,respectively.
Description:
The basic cluster data were taken from the Kharchenko et al. (2013,
Cat. J/A+A/558/A53), Schmeja et al. (2014, Cat. J/A+A/568/A51) and
Scholz et al. (2015, Cat. J/A+A/581/A39) which uses all-sky catalogue
2MASS (2Mass with Astrometry), that was extracted from the all-sky
catalogues PPMXL (Roeser et al. 2010, Cat. I/317) and 2MASS (Cutri et
al. 2003, Cat. II/246). Additionally, we incorporated data on masses
from Piskunov (2007, Cat. J/A+A/468/151/table2). We also added X, Y
and Z positions, and galactocentric distance of the clusters
determined in the present study.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 125 1241 Catalog of parameters for open clusters,
given by the increasing order of right ascension
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See also:
J/A+A/468/151 : Nearby open clusters radii and masses (Piskunov+, 2007)
J/A+A/558/A53 : MWSC II. The catalogue of basic parameters (Kharchenko+, 2013)
J/A+A/568/A51 : MWSC III. 139 new open clusters (Schmeja+, 2014)
J/A+A/581/A39 : MWSC IV. 63 new open clusters (Scholz+, 2015)
Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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1- 17 A17 --- Name Cluster name
19- 25 F7.4 h RAhour Right Ascension in decimal hours (J2000.0)
27- 33 F7.3 deg DEdeg Declination in decimal degrees (J2000.0)
35- 41 F7.3 deg GLON Galactic longitude
43- 49 F7.3 deg GLAT Galactic latitude
51- 57 F7.3 kpc Dist Distance from the Sun
59- 63 F5.3 mag E(B-V) Colour-excess in (B-V)
65- 69 F5.2 pc Diam Linear diameter
71- 74 F4.2 kpc Rgc Galactocentric distance
76- 80 F5.3 [yr] logt [6/10.1] Logarithm of average age
82- 86 F5.3 [yr] e_logt ?=0 Error of logt
88- 92 F5.2 Msun logM ?=99.99 Mass
94- 98 F5.2 Msun e_logM ?=99.99 Error of logM
100-107 F8.2 pc X Axes point toward the Galactic center
109-116 F8.2 pc Y Axes to the direction of Galactic rotation
118-125 F8.2 pc Z Axes to the North Galactic pole
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Acknowledgements:
Yogesh Chandra Joshi, yogesh(at)aries.res.in
(End) Patricia Vannier [CDS] 13-Jul-2016