ASTRONOMISCHE NACHRICHTEN, vol.345, no.8, pp.1-24, 2024 (SCI-Expanded)
This study outlines a detailed investigation using CCD UBV and Gaia DR3 data sets
of the two open clusters Ruprecht 1 (Rup-1) and Ruprecht 171 (Rup-171). Fundamental astrophysical parameters such as color excesses, photometric metallicities,
ages, and isochrone distances were based on UBV-data analyses, whereas membership probability calculations, structural and astrophysical parameters, as well as the
kinematic analyses were based on Gaia DR3-data. We identified 74 and 596 stars
as the most probable cluster members with membership probabilities over 50% for
Rup-1 and Rup-171, respectively. The color excesses 𝐸(𝐵 − 𝑉 ) were obtained as
0.166 ± 0.022 and 0.301 ± 0.027 mag for Rup-1 and Rup-171, respectively. Photometric metallicity analyses were performed by considering F-G type main-sequence
member stars and found to be [Fe/H]=−0.09 ± 0.16 and [Fe/H]=−0.20 ± 0.20 dex
for Rup-1 and Rup-171, respectively. Ages and distances were based on both UBV
and Gaia-data analyses; according to isochrone-fitting these values were estimated
to be 𝑡 = 580 ± 60 Myr, 𝑑 = 1469 ± 57 pc for Rup-1 and 𝑡 = 2700 ± 200 Myr,
𝑑 = 1509 ± 69 pc for Rup-171. The present-day mass function slope of Rup-1 was
estimated as 1.26 ± 0.32 and Rup-171 as 1.53 ± 1.49. Galactic orbit integration analyses showed that both of the clusters might be formed outside the solar circle.