Structure of Open Clusters - Gaia DR2 and its limitations

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F22%3A00125034" target="_blank" >RIV/00216224:14310/22:00125034 - isvavai.cz</a>

Result on the web

<a href="https://astro.bas.bg/AIJ/issues/n36/MPiecka.pdf" target="_blank" >https://astro.bas.bg/AIJ/issues/n36/MPiecka.pdf</a>

DOI - Digital Object Identifier

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Result language

angličtina

Original language name

Structure of Open Clusters - Gaia DR2 and its limitations

Original language description

Very precise observational data are needed for studying the stellar cluster parameters (distance, reddening, age, metallicity) and cluster internal kinematics. In turn, these give us an insight into the properties of our Galaxy, for example, by giving us the ability to trace Galactic spiral structure, star formation rates and metallicity gradients. We investigated the available Gaia DR2 catalogue of 1229 open clusters and studied cluster distances, sizes and membership distributions in the 3D space. An appropriate analysis of the parallax to-distance transformation problem is presented in the context of getting distances toward open clusters and estimating their sizes. Based on our investigation of the Gaia DR2 data we argue that, within 2 kpc, the inverse-parallax method gives comparable results (distances and sizes) as the Bayesian approach based on the exponentially decreasing volume density prior. Both of these methods show very similar dependence of the line-of-sight elongation of clusters (needle-like shapes resulting from the parallax uncertainties) on the distance. We also looked at a measure of elongations of the studied clusters and find the maximum distance of 665 pc at which a spherical fit still contains about half of the stellar population of a cluster. It follows from these results that the 3D structure of an open cluster cannot be properly studied beyond similar to 500 pc when using any of the mentioned standard transformations of parallaxes to distances.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10308 - Astronomy (including astrophysics,space science)

Project

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Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2022

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Bulgarian Astronomical Journal

ISSN

1313-2709

e-ISSN

1314-5592

Volume of the periodical

36

Issue of the periodical within the volume

July

Country of publishing house

BG - BULGARIA

Number of pages

27

Pages from-to

1-27

UT code for WoS article

000709909100001

EID of the result in the Scopus database

2-s2.0-85119957436