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Isotopes of Fermium (click to see decay chain): 242Fm  243Fm  244Fm  245Fm  246Fm  247Fm  248Fm  249Fm  250Fm  251Fm  252Fm  253Fm  254Fm  255Fm  256Fm  257Fm  258Fm  259Fm  260Fm

257Fm     Half-life Fermion, 100p 157n 100.4976851852 d Spin 9/2 Parity 1 Hide Decay Modes Probability Mode Decay Energy Daughter 100% α 6.86355MeV 253Cf 0.21% SF N/A Variable Hide Ultimate Decay Products Yield Nuclide 100.3267523065% 205Tl 6.959134788519×10-10% 207Pb Atomic Weight 257.095104724 Abundance None Mass Excess 88.589481MeV Binding Energy 7.422196MeV Magnetic Moment N/A Quadrupole Moment N/A   Show Isotope Symbols. Also show decay chains leading to this isotope. Show only decays with probability >0.1%. Show Decay Image Full Size.

Decay chain image generated by Mathematica's GraphPlot and IsotopeData functions from Wolfram Research, Inc..