The Annals of Applied Statistics

Streaming motion in Leo I

Bodhisattva Sen, Moulinath Banerjee, Michael Woodroofe, Mario Mateo, and Matthew Walker

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Whether a dwarf spheroidal galaxy is in equilibrium or being tidally disrupted by the Milky Way is an important question for the study of its dark matter content and distribution. This question is investigated using 328 recent observations from the dwarf spheroidal Leo I. For Leo I, tidal disruption is detected, at least for stars sufficiently far from the center, but the effect appears to be quite modest. Statistical tools include isotonic and split point estimators, asymptotic theory, and resampling methods.

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Ann. Appl. Stat., Volume 3, Number 1 (2009), 96-116.

First available in Project Euclid: 16 April 2009

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Asymptotic distributions bootstrap change point models dark matter dwarf spheroidal galaxies isotonic estimation permutation tests split points


Sen, Bodhisattva; Banerjee, Moulinath; Woodroofe, Michael; Mateo, Mario; Walker, Matthew. Streaming motion in Leo I. Ann. Appl. Stat. 3 (2009), no. 1, 96--116. doi:10.1214/08-AOAS211.

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