Protostars and Planets VI, Heidelberg, July 15-20, 2013

Poster 1K088

The Low-Mass Content of the Hyades stellar cluster

Goldman, Bertrand (MPIA)
Roeser, Siegfried (ARI)
Schilbach, Elena (ARI)
Henning, Thomas (MPIA)
Olczak, Christoph (ARI/MPIA)
Magnier, Eugene A. (IfA)

Abstract:
The Hyades cluster is an ideal target to study the dynamical evolution of a star cluster over the entire mass range due to its intermediate age and proximity to the Sun. We extend the Hyades mass function towards lower masses into the brown dwarf regime and use the full three-dimensional spatial information to characterize the dynamical evolution of the cluster. In addition, once binaries are identified, the new members will allow us to characterize the evolution of ultra-cool dwarfs at an age of 650 Myr. We perform a kinematic and photometric selection using the PPMXL and Pan-STARRS1 sky surveys, to search for cluster members up to 30 pc from the cluster centre. We determine our detection efficiency and field star contamination rate to derive the cluster luminosity and mass function. A minimum spanning tree algorithm is used to quantify the mass segregation. As likeliest candidates, we discover 43 new Hyades member candidates with mass estimates below 0.43 Msun, and double the number of low-mass member candidates. The cluster is significantly mass segregated. The extension of the mass function towards lower masses provides an even clearer signature than estimated before.

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