Solving the distance discrepancy for the open cluster NGC 2453: The planetary nebula NGC 2452 is not a cluster member

Abstract

<p><em>Context</em>. The open cluster (OC) NGC 2453 is of particular importance since it has been considered to host the planetary nebula (PN) NGC 2452, however their distances and radial velocities are strongly contested.</p> <p><em>Aims</em>. In order to obtain a complete picture of the fundamental parameters of the OC NGC 2453, 11 potential members were studied. The results allowed us to resolve the PN NGC 2452 membership debate.</p> <p><em>Methods</em>. Radial velocities for the 11 stars in NGC 2453 and the PN were measured and matched with <em>Gaia</em> data release 2 (DR2) to estimate the cluster distance. In addition, we used deep multi-band UBVRI photometry to get fundamental parameters of the cluster via isochrone fitting on the most likely cluster members, reducing inaccuracies due to field stars.</p> <p><em>Results</em>. The distance of the OC NGC 2453 (4.7 &plusmn; 0.2 kpc) was obtained with an independent method solving the discrepancy reported in the literature. This result is in good agreement with an isochrone fitting of 40&ndash;50 Myr. On the other hand, the radial velocity of NGC 2453 (78 &plusmn; 3 km s^&minus;1 ) disagrees with the velocity of NGC 2452 (62 &plusmn; 2 km s^&minus;1 ). Our results show that the PN is a foreground object in the line of sight.</p> <p><em>Conclusions</em>. Due to the discrepancies found in the parameters studied, we conclude that the PN NGC 2452 is not a member of the OC NGC 2453.</p>