CCD BV and 2MASS photometric study of the open cluster NGC 1513

Abstract

We present CCD BV and JHK${}_s$ 2MASS photometric data for the open cluster NGC 1513. We observed 609 stars in the direction of the cluster up to a limiting magnitude of $V\sim 19$ mag. The star count method shows that the centre of the cluster lies at $\hat{I}{\pm }_{2000}=04^{h}09^{m}36^s$, $\hat{I}{´}_{2000}=49^{\circ }28^{{}^{\prime }}43^{{}^{\prime \prime }}$ and its angular size is $r=10$ arcmin. The optical and near-infrared two-colour diagrams reveal the colour excesses in the direction of the cluster as $E(B-V)=0.68\pm 0.06$, $E(J-H)=0.21\pm 0.02$ and $E(J-K_s)=0.33\pm 0.04$ mag. These results are consistent with normal interstellar extinction values. Optical and near-infrared Zero Age Main-Sequences (ZAMS) provided an average distance modulus of $(m-M{)}_0=10.80\pm 0.13$ mag, which can be translated into a distance of $1440\pm 80$ pc. Finally, using Padova isochrones we determined the metallicity and age of the cluster as $Z=0.015\pm 0.004$ ($[M/H]=-0.10\pm 0.10$ dex) and $\log (t/yr)=8.40\pm 0.04$, respectively.

15 pages, 12 figures and 4 tables, accepted for publication in Astrophysics & Space Science