Isotopes of curium

Isotopes of curium (96Cm)
Main isotopes[1] Decay
abun­dance half-life (t1/2) mode pro­duct
242Cm synth 162.8 d α 238Pu
SF –
CD 208Pb
243Cm synth 29.1 y α 239Pu
ε 243Am
SF –
244Cm synth 18.11 y α 240Pu
SF –
245Cm synth 8250 y α 241Pu
SF –
246Cm synth 4760 y α 242Pu
SF –
247Cm synth 1.56×107 y α 243Pu
248Cm synth 3.480×105 y α 244Pu
SF –
250Cm synth 8300 y SF –
α 246Pu
β− 250Bk

Curium (96Cm) is an artificial element with an atomic number of 96. Because it is an artificial element, a standard atomic weight cannot be given, and it has no stable isotopes. The first isotope synthesized was 242Cm in 1944, which has 146 neutrons.

There are 19 known radioisotopes ranging from 233Cm to 251Cm. There are also ten known nuclear isomers. The longest-lived isotope is 247Cm, with half-life 15.6 million years – orders of magnitude longer than that of any known isotope beyond curium, and long enough to study as a possible extinct radionuclide that would be produced by the r-process.[2][3] The longest-lived known isomer is 246mCm with a half-life of 1.12 seconds.

  1. ^ Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae.
  2. ^ Côté, Benoit; Eichler, Marius; Yagüe López, Andrés; Vassh, Nicole; Mumpower, Matthew R.; Világos, Blanka; Soós, Benjámin; Arcones, Almudena; Sprouse, Trevor M.; Surman, Rebecca; Pignatari, Marco; Pető, Mária K.; Wehmeyer, Benjamin; Rauscher, Thomas; Lugaro, Maria (26 February 2021). "129I and 247Cm in meteorites constrain the last astrophysical source of solar r-process elements". Science. 371 (6532): 945–948. arXiv:2006.04833. Bibcode:2021Sci...371..945C. doi:10.1126/science.aba1111. PMID 33632846. S2CID 232050526.
  3. ^ Davis, A.M.; McKeegan, K.D. (2014). "Short-Lived Radionuclides and Early Solar System Chronology". Treatise on Geochemistry: 383. doi:10.1016/B978-0-08-095975-7.00113-3. ISBN 9780080983004.