English

Comprehensive Analysis of Middle-Aged Open Cluster NGC 6793 in Vulpecula via Gaia DR3 Data

Astrophysics of Galaxies 2025-03-26 v1

Abstract

We conducted an in-depth analysis of NGC 6793 open cluster via Gaia DR3 data, including astrometric, spectroscopic, and photometric measurements. Selection of 147 stars, which show membership probabilities P0.5P\geq0.5 were classified as likely members. The mean trigonometric parallaxes and proper-motion components of the cluster were found to be ϖ=1.674±0.045\varpi = 1.674 \pm0.045 mas and (μαcosδ\mu_{\alpha}\cos \delta,~μδ\mu_{\delta}) =(3.814±0.0313.814\pm0.031,~3.547±0.0343.547\pm0.034) mas yr1^{-1}. Fundamental astrophysical parameters of NGC 6793 are derived simultaneously as tt = 650±50650 \pm 50 Myr, μ\mu = 9.508±0.0709.508\pm0.070 mag, and E(GBPGRP)E(G_{\rm BP}-G_{\rm RP}) = 0.361±0.0350.361 \pm 0.035 mag. Additionally, the cluster's luminosity function analysis reveals the GG-absolute magnitude limit of the most likely stars, indicating a well-defined stellar population. The total mass of the cluster, determined through the mass function (MF) and considering stars with membership probabilities P0.5P \geq 0.5, was estimated as 139 ±\pm 12 M/MM/M_{\odot}. The slope of the MF was found to be Γ=1.40±0.26\Gamma = 1.40 \pm 0.26, a result consistent with the Salpeter value. The kinematic analyses present velocity ellipsoid parameters as well as the convergent point (Ao, Do)=(85.85±0.11, 3.12±0.57)(A_{\rm o},~D_{\rm o}) = \left(85^{\circ}.85 \pm 0^{\circ}.11,~3^{\circ}.12 \pm 0^{\circ}.57\right). Analyses have shown that it is moving in a box-shaped orbit beyond the Sun's galactic radius and belongs to the thin disk population of the Milky Way. The calculated relaxation time suggests that NGC 6793 has reached a dynamically relaxed state, where the dynamical evolution parameter τ\tau significantly exceeds one. These results highlight both the cluster's internal stability and its connection to the thin disc population.

Keywords

Cite

@article{arxiv.2503.19015,
  title  = {Comprehensive Analysis of Middle-Aged Open Cluster NGC 6793 in Vulpecula via Gaia DR3 Data},
  author = {Seval Taşdemir and Deniz Cennet Çınar and Remziye Canbay and Serkan Taştan and Waleed Elsanhoury and Aly Haroon},
  journal= {arXiv preprint arXiv:2503.19015},
  year   = {2025}
}

Comments

20 pages, 11 figures and 6 tables, accepted for publication in Physics and Astronomy Reports