Projects per year
Abstract
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.
Original language | English |
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Article number | 103 |
Number of pages | 11 |
Journal | The Astrophysical Journal |
Volume | 915 |
Issue number | 2 |
DOIs | |
Publication status | Published - 10 Jul 2021 |
Projects
- 2 Finished
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The stars that should not exist
Casey, A. (Primary Chief Investigator (PCI))
Australian Research Council (ARC)
28/08/19 → 31/12/22
Project: Research
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ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions
Kewley, L. (Primary Chief Investigator (PCI)), Stuart B Wyithe, J. (Chief Investigator (CI)), Sadler, E. M. (Chief Investigator (CI)), Staveley-Smith, L. (Chief Investigator (CI)), Glazebrook, K. (Chief Investigator (CI)), Jackson, C. (Chief Investigator (CI)), Bland-Hawthorn, J. (Chief Investigator (CI)), Asplund, M. B. (Chief Investigator (CI)), Trott, C. M. (Chief Investigator (CI)), Webster, R. (Chief Investigator (CI)), trenti, M. (Chief Investigator (CI)), Colless, M. (Chief Investigator (CI)), Croom, S. (Chief Investigator (CI)), Ryan-Weber, E. V. (Chief Investigator (CI)), Power, C. (Chief Investigator (CI)), Croton, D. J. (Chief Investigator (CI)), Driver, S. (Chief Investigator (CI)), Abraham, R. (Partner Investigator (PI)), Ball, L. (Partner Investigator (PI)), Bunker, A. (Partner Investigator (PI)), Couch, W. (Partner Investigator (PI)), Dalcanton, J. (Partner Investigator (PI)), Davies, R. L. (Partner Investigator (PI)), Gaensler, B. M. (Partner Investigator (PI)), Hopkins, A. (Partner Investigator (PI)), Kirby, E. (Partner Investigator (PI)), Koribalski, B. (Partner Investigator (PI)), Li, D. (Partner Investigator (PI)), Christopher Martin, D. (Partner Investigator (PI)), Morales, M. F. (Partner Investigator (PI)), Morganti, R. (Partner Investigator (PI)), Springel, V. (Partner Investigator (PI)), Wise, M. W. (Partner Investigator (PI)) & Karakas, A. (Chief Investigator (CI))
Monash University – Internal Faculty Contribution
30/06/17 → 31/12/24
Project: Research