Blue straggler populations of seven open clusters with Gaia DR2

Vaidya, Kaushar; Rao, Khushboo K; Agarwal, Manan; Bhattacharya, Souradeep

doi:10.1093/mnras/staa1667

Cited by 37 publications

(22 citation statements)

References 71 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…However, there are cases such as NGC 2477, whose AL07 BSS are all members, but that appear concentrated around the TO and sub-giant branch in the Gaia CMD. On the other hand, for close and very well studied clusters with spectroscopically confirmed BSS, it is possible to retrieve about 70% and in some cases up to 100%, as Vaidya et al (2020) have demonstrated. We are aware that some BSS are lost given our stringent and conservative selection criteria.…”

Section: Comparison With Al95 and Al07mentioning

confidence: 73%

A new, Gaia-based, catalogue of blue straggler stars in open clusters

Rain

Ahumada

Carraro

2021

A&A

View full text Add to dashboard Cite

Context. Blue straggler stars are exotic objects present in all stellar environments whose nature and formation channels are still partially unclear. They seem to be particularly abundant in open clusters (OCs), thus offering a unique chance to tackle these problems statistically. Aims. We aim to build up a new and homogeneous catalogue of blue straggler stars (BSS) in Galactic OCs using Gaia to provide a more solid assessment of the membership of these stars. We also aim to explore possible relationships of the straggler abundance with the parent cluster's structural and dynamical parameters. As a by-product, we also search for possible yellow straggler stars (YSS), which are believed to be stragglers in a more advanced evolution stage. Methods. We employed photometry, proper motions, and parallaxes extracted from Gaia DR2 for 408 Galactic star clusters and searched for stragglers within them after performing a careful membership analysis. Results. The number of BBS emerging from our more stringent, selection criteria turns out to be significantly smaller than in previous versions of this catalogue. OCs are therefore not a preferable environment for these kinds of stars anymore. In addition, we found that BSS start to appear in clusters with ages larger than log(t) ∼ 8.7 and are therefore absent in very young star clusters. Conclusions. The present catalogue supersedes the previous ones in several ways: membership assessment, number of stragglers found, and so forth. The new list includes 897 BSS and 77 YSS candidates in 408 OCs. We expect this catalogue to be the basis for a new round of studies of BSS and YSS.

show abstract

Section: Comparison With Al95 and Al07mentioning

confidence: 73%

A new, Gaia-based, catalogue of blue straggler stars in open clusters

Rain

Ahumada

Carraro

2021

A&A

View full text Add to dashboard Cite

show abstract

“…Bhattacharya et al 2017b), as well as through the radial distribution of massive objects, such as blue stragglers (e.g. Bhattacharya et al 2019;Vaidya et al 2020;Rao et al 2021). Alongside this internal effect, Galactic potential perturbs star clusters leading to the formation of tidal structures.…”

Section: Introductionmentioning

confidence: 99%

Tidal tails in the disintegrating open cluster NGC 752

Bhattacharya,

Agarwal,

Rao

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

We utilize the robust membership determination algorithm, ML-MOC, on the precise astrometric and deep photometric data from Gaia Early Data Release 3 within a region of radius 5 • around the center of the intermediate-age galactic open cluster NGC 752 to identify its member stars. We report the discovery of the tidal tails of NGC 752, extending out to ∼35 pc on either side of its denser central region and following the cluster orbit. From comparison with PARSEC stellar isochrones, we obtain the mass function of the cluster with a slope, 𝜒 = −1.26 ± 0.07. The high negative value of 𝜒 is indicative of a disintegrating cluster undergoing mass-segregation. 𝜒 is more negative in the intra-tidal regions as compared to the outskirts of NGC 752. We estimate a present day mass of the cluster, M C = 297 ± 10 M . Through mass-loss due to stellar evolution and tidal interactions, we further estimate that NGC 752 has lost nearly 95.2-98.5% of its initial mass, M i = 0.64 − 2 × 10 4 M .

show abstract

“…Our method for assessing membership using proper motions and parallaxes from Gaia DR2 decreases, but does not remove all the contamination by such field young stars. To do so, and following Vaidya et al (2020), we limited each cluster's radius to that at which there are more cluster stars than field stars. We estimated the cluster size as the radius R where the cluster density profile sepa- 3.…”

Section: Field Contaminationmentioning

confidence: 99%

“…Finally, in the Family III class of GCs, the external maximum disappears, and the only noticeable peak in the distribution is the central one, followed by a minimum. A similar work in open clusters has been carried out by Vaidya et al (2020). The authors determined accurate stellar membership and studied the BS radial distribution on seven open clusters.…”

Section: Introductionmentioning

confidence: 97%

The blue straggler population of the open clusters Trumpler 5, Trumpler 20, and NGC 2477

Rain,

Carraro,

Ahumada

et al. 2020

Preprint

View full text Add to dashboard Cite

We present a study, based on Gaia DR2, of the population of blue straggler stars (BSS) in the open clusters Trumpler 5, Trumpler 20, and NGC 2477. All candidates were selected according to their position in the color-magnitude diagram, to their proper motion components, and to their parallax. We also looked for yellow stragglers, i.e., possible evolved blue stragglers. We found that Trumpler 5 hosts a large BSS population, which allowed us to analyze their radial distribution as a probe of the cluster's dynamical status. The BSS distribution was compared with that of red giant branch stars (RGB) to evaluate mass segregation. Our results indicate that BSS are not more centrally concentrated than RGB stars in any of the clusters. The radial distribution of BSS in Trumpler 5 is flat. Additionally, using a multi-epoch radial velocity survey conducted with the high-resolution spectrograph FLAMES/GIRAFFE at VLT, we measured the radial velocities of a sample of stragglers, for the sake of comparison with the mean radial velocity and velocity dispersion of the clusters. Based on the radial velocity variations for different epochs, we roughly classified these stars as possible closeor long-period binaries.

show abstract

Blue straggler populations of seven open clusters with Gaia DR2

Cited by 37 publications

References 71 publications

A new, Gaia-based, catalogue of blue straggler stars in open clusters

A new, Gaia-based, catalogue of blue straggler stars in open clusters

Tidal tails in the disintegrating open cluster NGC 752

The blue straggler population of the open clusters Trumpler 5, Trumpler 20, and NGC 2477

Contact Info

Product

Resources

About