# CCD UBVRI photometry of the open cluster Berkeley 8

## TL;DR

This study provides detailed photometric analysis of the open cluster Berkeley 8, determining its fundamental parameters and kinematic properties, and compares these with Gaia data to understand its Galactic context.

## Contribution

First detailed CCD UBVRI photometry and analysis of Berkeley 8, including distance, age, reddening, and kinematic properties, with comparison to Gaia data.

## Key findings

- Distance of 3410 +- 300 pc from photometry, 3676 +- 810 pc from Gaia
- Age of 2.8 +- 0.2 Gyr for Berkeley 8
- Kinematic parameters consistent with Galactic thin disc

## Abstract

The poorly studied Berkeley 8 (Be8) open cluster is analysed from CCD UBVRI photometric data taken with the 0.90 m telescope at the Sierra Nevada Observatory. The Z = +0.008 PARSEC isochrone gave us a reddening of E(B-V) = 0.69 +- 0.03, a distance of 3410 +- 300 pc and an age of 2.8 +- 0.2 Gyr. Its median Gaia DR2 distance, d = 3676 +- 810 pc is in good agreement with our photometric distances, 3410 - 3620 pc within the uncertainties. The kinematic parameters of five likely members of Be 8 with the circular orbits, ecc = [0.23, 0.30] reflect the properties of the Galactic thin disc, which is also consistent with what is expected of its metal content ([M/H] = -0.27). Be8 with R > 9 kpc (co-rotation gap at 9 kpc) may have been originating from different galactic radius or different star formation region.