A deep IZ survey of 1.1 deg2 of the Pleiades cluster: three candidate members with M < 0.04 Msolar

The results of an I - and Z -band survey and infrared follow-up of 1.1 deg 2 of the Pleiades open cluster complete to I ≈ 21.4 ( I c ∼ 22) are presented. A total of 23 candidate cluster members has been unearthed, 15 of which are previously unpublished. Assuming canonical cluster age and distance, and using the latest theoretical models, we determine that the cluster mass function continues to rise down to a mass of 0.03 M⊙, following a power law with α = 0.8. By considering several potential sources of uncertainty we show that this result is robust and we compare it with the results from other work on young clusters.

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