Kinematic evidence for an old stellar halo in the Large Magellanic Cloud

Minniti, D; Borissova, J.; Rejkuba, M; Alves, DR; Cook, KH; Freeman, KC

Abstract

The oldest and most metal-poor Milky Way stars form a kinematically hot halo, which motivates the two major formation scenarios for our galaxy: extended hierarchical accretion and rapid collapse. RR Lyrae stars are excellent tracers of old and metal-poor populations. We measured the kinematics of 43 RR Lyrae stars in the inner regions of the nearby Large Magellanic Cloud (LMC) galaxy. The velocity dispersion equals 53 ± 10 kilometers per second, which indicates that a kinematically hot metal-poor old halo also exists in the LMC. This result suggests that our galaxy and smaller late-type galaxies such as the LMC have similar early formation histories.

Más información

Título según WOS: Kinematic evidence for an old stellar halo in the Large Magellanic Cloud
Título según SCOPUS: Kinematic evidence for an old stellar halo in the large Magellanic Cloud
Título de la Revista: SCIENCE
Volumen: 301
Número: 5639
Editorial: AMER ASSOC ADVANCEMENT SCIENCE
Fecha de publicación: 2003
Página de inicio: 1508
Página final: 1510
Idioma: English
URL: http://www.sciencemag.org/cgi/doi/10.1126/science.1088529
DOI:

10.1126/science.1088529

Notas: ISI, SCOPUS