Anamalous positive magnetization signal at the onset of normal to superconductor transition in single crystal Nb sphere by P. D. Kulkarni; S. S. Banerjee; H. Suderow; H. Takeya; S. Ramakrishnan

We report the observation of positive magnetization signal at the onset of superconducting transition in isothemral and isomagnetic measurements in single crystal Niobium sphere. The PME displays two regimes, viz., low applied magnetic fields H < 4 Oe) and higher fields H > 120 Oe, and the PME signal is absent at the intermediate magnetic fields. Subsequently, the isothermal magnetization data shows the presence of positive signal at the superconductor to normal transition. Using this data we are able to plot the H(c3)-T(c3) line, at which the positive magnetization signal nucleates, in the phase diagram of single crystal Nb.