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arXiv · astro-ph/0511166

Ultra low-mass star and substellar formation in sigma Orionis

J. A. Caballero
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Abstract

The nearby young sigma Orionis cluster (~360 pc, ~3 Ma) is becoming one of the most important regions for the study of ultra low-mass star formation and its extension down to the mass regimes of the brown dwarfs and planetary-mass objects. Here, I introduce the sigma Orionis cluster and present three studies that the JOVIAN group is developing: a pilot programme of near-infrared adaptive-optics imaging, intermediate-resolution optical spectroscopy of a large sample of stars of the cluster and a study of the mass function down to the planetary-mass domain. This paper is a summary of the content of four posters that I presented in the Ultra low-mass star formation and evolution Workshop, as single author or on behalf of different collaborations.

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J. A. Caballero. 2005-11-07. Ultra low-mass star and substellar formation in sigma Orionis. https://doi.org/10.1002/asna.200510468

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