SCYON Abstract

Received on April 23 2001

Star clusterings in the Carina complex: UBVRI photometry of Bochum 9, 10 and 11

AuthorsF. Patat(1), G. Carraro(2)
Affiliation(1) ESO
(2) Padova
Accepted byMonthly Notices of the Royal Astronomical Society
Links Bochum 9 / Bochum 10 / Bochum 11


We report on the first UBVRI CCD photometry of three poorly known star clusterings in the region of eta Carinae: Bochum 9, Bochum 10 and Bochum 11. We found that they are young, rather poor and loose open clusters.
We argue that Bochum 9 is probably a small and loose open cluster with about 30 probable members having E(B-V) = 0.63 ± 0.08, located 4.6 kpc far from the Sun, beyond the Carina spiral arm.
Similarly, Bochum 10 is a sparse aggregate with 14 probable members having E(B-V) = 0.47 ± 0.05 and at a distance of 2.7 kpc from the Sun.
Finally, Bochum 11 is a less than 4 x 106 yrs old cluster for which we identify 24 members. It has a reddening E(B-V) = 0.58 ± 0.05, and lies between Bochum 10 and 9, at 3.5 kpc from the Sun. We propose that in the field of the cluster some stars might be pre Main Sequence (MS) candidates.