The globular cluster ω Centauri shows the largest spread in chemical element abundances of known clusters. We discuss the recent proposal that the most metal-rich stars have a bulk transverse motion with respect to the other cluster members and show that this could arise as a spurious effect resulting from a residual color/magnitude-related term in the proper motions. We briefly discuss the possibility of self-enrichment for this most metal-rich component, including Type la supernovae ejecta.
Bibliographical noteFunding Information:
We thank J. Norris, J. Pringle, and C. Pryor for useful discussions and two referees for a number of suggestions. This work has been supported in part by NSF grant AST 03-21794 to Johns Hopkins University (I. P.). Y.-W. L. and S.-C. R. acknowledge support from the Creative Research Initiative Program of the Korean Ministry of Science and Technology.
All Science Journal Classification (ASJC) codes
- Astronomy and Astrophysics
- Space and Planetary Science