Projects per year
The recently discovered Indus stellar stream exhibits a diverse chemical signature compared to what is found for most other streams due to the abundances of two outlier stars, Indus_0 and Indus_13. Indus_13 exhibits an extreme enhancement in rapid neutron-capture (r-)process elements with [Eu/Fe] = + 1.81. It thus provides direct evidence of the accreted nature of r-process-enhanced stars. In this paper we present a detailed chemical analysis of the neutron-capture elements in Indus_13, revealing the star to be slightly actinide poor. The other outlier, Indus_0, displays a globular cluster-like signature with high N, Na, and Al abundances, while the rest of the Indus stars show abundances compatible with a dwarf galaxy origin. Hence, Indus_0 provides the first chemical evidence of a fully disrupted dwarf containing a globular cluster. We use the chemical signature of the Indus stars to discuss the nature of the stream progenitor which was likely a chemically evolved system, with a mass somewhere in the range from Ursa Minor to Fornax.
|Number of pages||11|
|Journal||The Astrophysical Journal|
|Publication status||Published - 10 Jul 2021|
ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions
Kewley, L., Stuart B Wyithe, J., Sadler, E. M., Staveley-Smith, L., Glazebrook, K., Jackson, C., Bland-Hawthorn, J., Asplund, M. B., Trott, C. M., Webster, R., trenti, M., Colless, M., Croom, S., Ryan-Weber, E. V., Power, C., Croton, D. J., Driver, S., Abraham, R., Ball, L., Bunker, A., Couch, W., Dalcanton, J., Davies, R. L., Gaensler, B. M., Hopkins, A., Kirby, E., Koribalski, B., Li, D., Christopher Martin, D., Morales, M. F., Morganti, R., Springel, V., Wise, M. W. & Karakas, A.
Monash University – Internal Faculty Contribution
30/06/17 → 30/06/24
The stars that should not exist
Australian Research Council (ARC)
28/08/19 → 31/12/22