We report specific heat measurements at magnetic fields up to 20 T on the recently discovered superconductor SmFeAsO 0.85 F 0.15 . The B-T diagram of a polycrystalline SmFeAsO 0.85 F 0.15 sample with T c = 46 K was investigated. The temperature dependence of B c2 was extracted from the specific heat curves, the corresponding B c2 (T = 0) value derived from the Werthamer-Helfand-Hohenberg formula being 150 T. Based on magnetization measurements up to 9 T, a first estimation of the field dependence of the inductive critical current J c is given. Evidence for granularity is found. The presence of a peak effect is reported, suggesting a crossover in the vortex dynamics, in analogy to the behaviour observed in high T c cuprates.

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