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Related papers: Cluster radius and sampling radius in the determin…

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In this work we improve a previously published method to calculate in a reliable way the radius of an open cluster. The method is based on the behaviour of stars in the proper motion space as the sampling changes in the position space. Here…

Astrophysics of Galaxies · Physics 2020-05-27 Nestor Sanchez , Emilio Alfaro , Fatima Lopez-Martinez

We propose a method for calculating the radius of an open cluster in an objective way from an astrometric catalogue containing, at least, positions and proper motions. It uses the minimum spanning tree (hereinafter MST) in the proper motion…

Astrophysics of Galaxies · Physics 2018-01-24 Nestor Sanchez , Emilio J. Alfaro , Fatima Lopez-Martinez

Interstellar polarimetric data of the six open clusters Hogg 15, NGC 6611, NGC 5606, NGC 6231, NGC 5749 and NGC 6250 have been used to estimate the membership probability for the stars within them. For proper-motion member stars, the…

Astrophysics of Galaxies · Physics 2015-06-12 Biman J. Medhi , Motohide Tamura

We present a new geometrical method aimed at determining the members of open clusters. The methodology estimates, in an N-dimensional space, the membership probabilities by means of the distances between every star and the cluster central…

Solar and Stellar Astrophysics · Physics 2016-02-10 Laura Sampedro , Emilio J. Alfaro

Using the linear polarimetric observations, we present a method to derive the membership probability of stars in cluster NGC 2345. The polarimetric observations of cluster NGC 2345 are performed using the instrument ARIES IMaging…

Solar and Stellar Astrophysics · Physics 2023-08-17 Sadhana Singh , Jeewan C. Pandey , Vishal Joshi

Membership analysis is an important tool for studying star clusters. There are various approaches to membership determination, including supervised and unsupervised machine learning (ML) methods. We perform membership analysis using the…

Astrophysics of Galaxies · Physics 2024-09-25 A. Bissekenov , M. Kalambay , E. Abdikamalov , X. Pang , P. Berczik , B. Shukirgaliyev

Membership of stars in open clusters is one of the most crucial parameters in studies of star clusters. Gaia opened a new window in the estimation of membership because of its unprecedented 6-D data. In the present study, we used published…

Solar and Stellar Astrophysics · Physics 2021-07-28 Md Mahmudunnobe , Priya Hasan , Mudasir Raja , S N Hasan

Relative proper motions and cluster membership probabilities have been derived for ~ 2500 stars in the field of the open star cluster NGC 3766. The cluster has been observed in $B$ and $V$ broadband filters at two epochs separated by ~ 6…

Astrophysics of Galaxies · Physics 2015-06-15 R. K. S. Yadav , Devesh P. Sariya , R. Sagar

Clusters of galaxies are important laboratories for understanding both galaxy evolution and constraining cosmological quantities. Any analysis of clusters, however, is best done when one can reliably determine which galaxies are members of…

Astrophysics · Physics 2009-10-31 R. J. Brunner , L. M. Lubin

In order to study the galaxy population of galaxy clusters with photometric data one must be able to accurately discriminate between cluster members and non-members. The redMaPPer cluster finding algorithm treats this problem…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-19 Eduardo Rozo , Eli S. Rykoff , Matthew Becker , Rachel M. Reddick , Risa H. Wechsler

Star clusters are interesting laboratories to study star formation, single and binary stellar evolution, and stellar dynamics. We have used the exquisite data from $Gaia$'s data release 3 (DR3) to study 21 relatively rich and nearby open…

Solar and Stellar Astrophysics · Physics 2025-09-03 Anindya Ganguly , Prasanta K. Nayak , Sourav Chatterjee

The existing open cluster membership determination algorithms are either prior dependent on some known parameters of clusters or are not automatable to large samples of clusters. In this paper, we present, ML-MOC, a new machine learning…

Instrumentation and Methods for Astrophysics · Physics 2021-02-16 Manan Agarwal , Khushboo K. Rao , Kaushar Vaidya , Souradeep Bhattacharya

We introduce a new method to determine galaxy cluster membership based solely on photometric properties. We adopt a machine learning approach to recover a cluster membership probability from galaxy photometric parameters and finally derive…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-26 P. A. A. Lopes , A. L. B. Ribeiro

We have made a new compilation of observations of maximum stellar mass versus cluster membership number from the literature, which we analyse for consistency with the predictions of a simple random drawing hypothesis for stellar mass…

Astrophysics · Physics 2009-11-13 Th. Maschberger , C. J. Clarke

The open clusters fundamental physical parameters are important tools to understand the formation and evolution of the Galactic disk and as grounding tests for star formation and evolution models. However only a small fraction of the known…

Astrophysics of Galaxies · Physics 2010-05-24 Wagner J. B. Corradi , Francisco F. S. Maia , Joao F. C. Santos

We present a statistical system that can be used in the study of cluster populations. The basis of our approach is the construction of synthetic cluster color-magnitude-radius diagrams (CMRDs), which we compare with the observed data using…

Astrophysics · Physics 2012-08-27 Andrew E. Dolphin , Robert C. Kennicutt,

Stars form predominantly in groups usually denoted as clusters or associations. The observed stellar groups display a broad spectrum of masses, sizes and other properties, so it is often assumed that there is no underlying structure in this…

Solar and Stellar Astrophysics · Physics 2016-02-03 S. Pfalzner , H. Kirk , A. Sills , J. S. Urquhart , J. Kauffmann , M. A. Kuhn , A. Bhandare , K. M. Menten

In this paper, we apply the machine learning clustering algorithm Density Based Spatial Clustering of Applications with Noise (DBSCAN) to study the membership of stars in twelve open clusters (NGC~2264, NGC~2682, NGC~2244, NGC~3293,…

Astrophysics of Galaxies · Physics 2024-04-17 Mudasir Raja , Priya Hasan , Md Mahmudunnobe , Md Saifuddin , S N Hasan

A combination of two unsupervised machine learning algorithms, DBSCAN and GMM are used to find members with a high probability of twelve open clusters, M38, NGC2099, Coma Ber, NGC752, M67, NGC2243, Alessi01, Bochum04, M34, M35, M41, and…

Astrophysics of Galaxies · Physics 2023-05-30 Mohammad Noormohammadi , Mehdi Khakian Ghomi , Hossein Haghi

The primary difficulty in measuring dynamical masses of galaxy clusters from galaxy data lies in the separation between true cluster members from interloping galaxies along the line of sight. We study the impact of membership contamination…

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