Discovery of an open cluster with a possible physical association with a planetary nebula

We report the discovery of a new open cluster (OC) in the Galaxy at and ⁠. Its field includes the planetary nebula (PN) PK 167−0.1. We study the possible associations of the PN/OC pairs NGC 2818/2818A, NGC 2438/M 46 (NGC 2437), PK 6+2.5/NGC 6469, as well as of the PN PK 167−0.1 with New Cluster 1. The analyses are based on near-infrared colour–magnitude diagrams (CMDs) and stellar radial density profiles. NGC 6469 is located in a heavily contaminated bulge field. The CMD morphology, especially for the latter two cases, is defined with a field-star decontamination algorithm applied to the 2MASS J, H and Ks photometry. Field decontamination for the OCs NGC 2818A and M 46 produced better defined CMDs and more accurate cluster parameters than in the literature. Those pieces of evidence point to M 46 as physically associated with the PN NGC 2438. The same occurs for the OC NGC 2818A and the PN NGC 2818; however, previous radial velocity arguments indicate that they are not associated. The OC NGC 6469 does not appear to be associated with the PN PK 6+2.5, which probably belongs to the bulge. Finally, the distance of the OC New Cluster 1 is consistent with a physical association with the PN PK 167−0.1.