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A brown dwarf candidate in the Praesepe Open Cluster

A. Magazzu·R. Rebolo·M. R. Zapatero Osorio·E. L. Martin·S. T. Hodgkin
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Abstract

We present optical and infrared observations of RPr1, a faint (I = 21.01) and very red object (I - K = 4.57) discovered in a deep CCD survey, covering an area of 800 square arcmin of the Praesepe open cluster. A low resolution spectrum shows that RPr1 is a very late object, the latest object in Praesepe for which a spectrum has been taken to date. Our estimates give a mass between 0.063 and 0.084 solar masses, and indicate that RPr1 may turn out to be the first brown dwarf in this cluster.

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A. Magazzu, R. Rebolo, M. R. Zapatero Osorio, E. L. Martin, S. T. Hodgkin. 1998-02-13. A brown dwarf candidate in the Praesepe Open Cluster. https://doi.org/10.1086/311273

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