Based on a review of comprehensive nuclear data, the elements with the most isotopes are Xenon (Xe) and Caesium (Cs), with 36 isotopes each.1

Both elements have a large number of radioactive isotopes.2 Xenon is notable for having the most stable isotopes of any element, with a total of nine, while Caesium only has one.3

This is the most common answer to this question, but it is important to note that the exact number of known isotopes is constantly being updated as new research is conducted.

Xenon (Xe)

  • Atomic Number: 544
  • Symbol: Xe5
  • Number of Isotopes: 36 (9 stable, 27 radioactive)6
  • Key Isotopes:
    • 136Xe: The most abundant stable isotope.
    • 124Xe: The lightest stable isotope.
    • 126Xe: An extremely long-lived radioactive isotope.
    • 133Xe: A key radioactive isotope used in medical imaging with a half-life of 5.247 days.
    • 129Xe: One of the stable isotopes with a wide range of applications, including in medical imaging and as a propellant for ion engines.

Caesium (Cs)

  • Atomic Number: 55
  • Symbol: Cs
  • Number of Isotopes: 36 (1 stable, 35 radioactive)7
  • Key Isotopes:
    • 133Cs: The only stable isotope.8
    • 137Cs: A highly dangerous radioactive isotope with a half-life of 30.07 years, produced in nuclear reactors and released during nuclear disasters. It decays via beta decay.
    • 135Cs: Another long-lived radioactive isotope with a half-life of 2.3 million years, produced in nuclear fission.
    • 131Cs: An isotope used in brachytherapy for cancer treatment with a half-life of 9.689 days.

Antimony (Sb) – Neodymium (Nd)

Antimony (Sb)

  • Atomic Number: 51
  • Symbol: Sb
  • Isotopes:
    • $^{104}$Sb: Half-life is 200 ms, decays via β+ (positron emission) and proton emission.
    • $^{105}$Sb: Half-life is 1.12 s, decays via β+ (positron emission).
    • $^{106}$Sb: Half-life is 2.15 s, decays via β+ (positron emission).
    • $^{107}$Sb: Half-life is 3.26 s, decays via β+ (positron emission).
    • $^{108}$Sb: Half-life is 6.5 s, decays via β+ (positron emission).
    • $^{109}$Sb: Half-life is 17.6 s, decays via β+ (positron emission).
    • $^{110}$Sb: Half-life is 23.4 s, decays via β+ (positron emission).
    • $^{111}$Sb: Half-life is 75 s, decays via β+ (positron emission).
    • $^{112}$Sb: Half-life is 5.1 min, decays via β+ (positron emission).
    • $^{113}$Sb: Half-life is 6.67 min, decays via β+ (positron emission).
    • $^{114}$Sb: Half-life is 3.50 min, decays via β+ (positron emission).
    • $^{115}$Sb: Half-life is 32.1 min, decays via β+ (positron emission).
    • $^{116}$Sb: Half-life is 15.6 min, decays via β+ (positron emission) and electron capture.
    • $^{117}$Sb: Half-life is 2.80 h, decays via β+ (positron emission) and electron capture.
    • $^{118}$Sb: Half-life is 3.6 min, decays via β+ (positron emission) and electron capture.
    • $^{119}$Sb: Half-life is 38.0 h, decays via electron capture.
    • $^{120}$Sb: Half-life is 5.76 d, decays via β+ (positron emission) and electron capture.
    • $^{121}$Sb: Stable.
    • $^{122}$Sb: Half-life is 2.723 d, decays via β− (beta decay).
    • $^{123}$Sb: Stable.
    • $^{124}$Sb: Half-life is 60.20 d, decays via β− (beta decay).
    • $^{125}$Sb: Half-life is 2.758 y, decays via β− (beta decay).
    • $^{126}$Sb: Half-life is 19.1 min, decays via β− (beta decay).
    • $^{127}$Sb: Half-life is 3.85 h, decays via β− (beta decay).
    • $^{128}$Sb: Half-life is 9.01 h, decays via β− (beta decay).
    • $^{129}$Sb: Half-life is 4.40 h, decays via β− (beta decay).
    • $^{130}$Sb: Half-life is 39.5 min, decays via β− (beta decay).
    • $^{131}$Sb: Half-life is 23.03 min, decays via β− (beta decay).
    • $^{132}$Sb: Half-life is 2.79 min, decays via β− (beta decay) and neutron emission.
    • $^{133}$Sb: Half-life is 2.47 min, decays via β− (beta decay) and neutron emission.
    • $^{134}$Sb: Half-life is 1.10 s, decays via β− (beta decay) and neutron emission.
    • $^{135}$Sb: Half-life is 1.6 s, decays via β− (beta decay) and neutron emission.
    • $^{136}$Sb: Half-life is 800 ms, decays via β− (beta decay) and neutron emission.
    • $^{137}$Sb: Half-life is 250 ms, decays via β− (beta decay) and neutron emission.

Tellurium (Te)

  • Atomic Number: 52
  • Symbol: Te
  • Isotopes:
    • $^{106}$Te: Half-life is 70 ms, decays via β+ (positron emission) and proton emission.
    • $^{107}$Te: Half-life is 3.1 ms, decays via β+ (positron emission).
    • $^{108}$Te: Half-life is 2.1 s, decays via β+ (positron emission) and alpha decay.
    • $^{109}$Te: Half-life is 4.6 s, decays via β+ (positron emission) and alpha decay.
    • $^{110}$Te: Half-life is 18.3 s, decays via β+ (positron emission).
    • $^{111}$Te: Half-life is 1.05 min, decays via β+ (positron emission).
    • $^{112}$Te: Half-life is 2.0 min, decays via β+ (positron emission).
    • $^{113}$Te: Half-life is 2.5 min, decays via β+ (positron emission).
    • $^{114}$Te: Half-life is 15.2 min, decays via β+ (positron emission).
    • $^{115}$Te: Half-life is 5.8 min, decays via β+ (positron emission).
    • $^{116}$Te: Half-life is 2.49 h, decays via β+ (positron emission) and electron capture.
    • $^{117}$Te: Half-life is 6.2 min, decays via β+ (positron emission) and electron capture.
    • $^{118}$Te: Half-life is 6.0 d, decays via electron capture.
    • $^{119}$Te: Half-life is 16.0 h, decays via β+ (positron emission) and electron capture.
    • $^{120}$Te: Stable.
    • $^{121}$Te: Half-life is 19.17 d, decays via electron capture.
    • $^{122}$Te: Stable.
    • $^{123}$Te: Stable.
    • $^{124}$Te: Stable.
    • $^{125}$Te: Stable.
    • $^{126}$Te: Stable.
    • $^{127}$Te: Half-life is 9.35 h, decays via β− (beta decay).
    • $^{128}$Te: Stable.
    • $^{129}$Te: Half-life is 69.6 min, decays via β− (beta decay).
    • $^{130}$Te: Stable.
    • $^{131}$Te: Half-life is 25.0 min, decays via β− (beta decay).
    • $^{132}$Te: Half-life is 78.2 h, decays via β− (beta decay).
    • $^{133}$Te: Half-life is 12.5 min, decays via β− (beta decay) and neutron emission.
    • $^{134}$Te: Half-life is 41.8 min, decays via β− (beta decay) and neutron emission.
    • $^{135}$Te: Half-life is 19.0 s, decays via β− (beta decay) and neutron emission.
    • $^{136}$Te: Half-life is 17.5 s, decays via β− (beta decay) and neutron emission.
    • $^{137}$Te: Half-life is 2.49 s, decays via β− (beta decay) and neutron emission.
    • $^{138}$Te: Half-life is 1.54 s, decays via β− (beta decay) and neutron emission.

Iodine (I)

  • Atomic Number: 53
  • Symbol: I
  • Isotopes:
    • $^{110}$I: Half-life is 2.42 s, decays via β+ (positron emission).
    • $^{111}$I: Half-life is 2.5 s, decays via β+ (positron emission).
    • $^{112}$I: Half-life is 3.4 s, decays via β+ (positron emission).
    • $^{113}$I: Half-life is 6.6 s, decays via β+ (positron emission).
    • $^{114}$I: Half-life is 2.1 s, decays via β+ (positron emission).
    • $^{115}$I: Half-life is 1.4 min, decays via β+ (positron emission).
    • $^{116}$I: Half-life is 2.91 min, decays via β+ (positron emission).
    • $^{117}$I: Half-life is 3.34 min, decays via β+ (positron emission).
    • $^{118}$I: Half-life is 13.7 min, decays via β+ (positron emission).
    • $^{119}$I: Half-life is 19.1 min, decays via β+ (positron emission).
    • $^{120}$I: Half-life is 1.35 h, decays via β+ (positron emission) and electron capture.
    • $^{121}$I: Half-life is 2.12 h, decays via β+ (positron emission) and electron capture.
    • $^{122}$I: Half-life is 3.63 min, decays via β+ (positron emission).
    • $^{123}$I: Half-life is 13.22 h, decays via electron capture.
    • $^{124}$I: Half-life is 4.176 d, decays via β+ (positron emission) and electron capture.
    • $^{125}$I: Half-life is 59.4 d, decays via electron capture.
    • $^{126}$I: Half-life is 13.0 d, decays via β+ (positron emission), electron capture, and β− (beta decay).
    • $^{127}$I: Stable.
    • $^{128}$I: Half-life is 24.99 min, decays via β− (beta decay) and electron capture.
    • $^{129}$I: Half-life is 1.57 x 107 y, decays via β− (beta decay).
    • $^{130}$I: Half-life is 12.36 h, decays via β− (beta decay).
    • $^{131}$I: Half-life is 8.0207 d, decays via β− (beta decay).
    • $^{132}$I: Half-life is 2.295 h, decays via β− (beta decay).
    • $^{133}$I: Half-life is 20.8 h, decays via β− (beta decay).
    • $^{134}$I: Half-life is 52.6 min, decays via β− (beta decay).
    • $^{135}$I: Half-life is 6.57 h, decays via β− (beta decay).
    • $^{136}$I: Half-life is 83.4 s, decays via β− (beta decay) and neutron emission.
    • $^{137}$I: Half-life is 24.5 s, decays via β− (beta decay) and neutron emission.
    • $^{138}$I: Half-life is 6.2 s, decays via β− (beta decay) and neutron emission.
    • $^{139}$I: Half-life is 2.2 s, decays via β− (beta decay) and neutron emission.

Xenon (Xe)

  • Atomic Number: 54
  • Symbol: Xe
  • Isotopes:
    • $^{113}$Xe: Half-life is 2.74 s, decays via β+ (positron emission).
    • $^{114}$Xe: Half-life is 10.0 s, decays via β+ (positron emission).
    • $^{115}$Xe: Half-life is 18 s, decays via β+ (positron emission).
    • $^{116}$Xe: Half-life is 59 s, decays via β+ (positron emission).
    • $^{117}$Xe: Half-life is 61 s, decays via β+ (positron emission).
    • $^{118}$Xe: Half-life is 3.8 min, decays via β+ (positron emission).
    • $^{119}$Xe: Half-life is 5.8 min, decays via β+ (positron emission).
    • $^{120}$Xe: Half-life is 40 min, decays via β+ (positron emission).
    • $^{121}$Xe: Half-life is 38.8 min, decays via β+ (positron emission).
    • $^{122}$Xe: Half-life is 20.1 h, decays via electron capture.
    • $^{123}$Xe: Half-life is 2.08 h, decays via β+ (positron emission) and electron capture.
    • $^{124}$Xe: Stable.
    • $^{125}$Xe: Half-life is 16.9 h, decays via electron capture.
    • $^{126}$Xe: Stable.
    • $^{127}$Xe: Half-life is 36.34 d, decays via electron capture.
    • $^{128}$Xe: Stable.
    • $^{129}$Xe: Stable.
    • $^{130}$Xe: Stable.
    • $^{131}$Xe: Stable.
    • $^{132}$Xe: Stable.
    • $^{133}$Xe: Half-life is 5.247 d, decays via β− (beta decay).
    • $^{134}$Xe: Stable.
    • $^{135}$Xe: Half-life is 9.14 h, decays via β− (beta decay).
    • $^{136}$Xe: Stable.
    • $^{137}$Xe: Half-life is 3.818 min, decays via β− (beta decay).
    • $^{138}$Xe: Half-life is 14.08 min, decays via β− (beta decay).
    • $^{139}$Xe: Half-life is 39.7 s, decays via β− (beta decay).
    • $^{140}$Xe: Half-life is 13.6 s, decays via β− (beta decay) and neutron emission.
    • $^{141}$Xe: Half-life is 1.73 s, decays via β− (beta decay) and neutron emission.
    • $^{142}$Xe: Half-life is 1.22 s, decays via β− (beta decay) and neutron emission.
    • $^{143}$Xe: Half-life is 455 ms, decays via β− (beta decay) and neutron emission.
    • $^{144}$Xe: Half-life is 380 ms, decays via β− (beta decay) and neutron emission.
    • $^{145}$Xe: Half-life is 190 ms, decays via β− (beta decay) and neutron emission.
    • $^{146}$Xe: Half-life is 140 ms, decays via β− (beta decay) and neutron emission.
    • $^{147}$Xe: Half-life is 80 ms, decays via β− (beta decay) and neutron emission.

Cesium (Cs)

  • Atomic Number: 55
  • Symbol: Cs
  • Isotopes:
    • $^{112}$Cs: Half-life is 500 ns, decays via proton emission.
    • $^{113}$Cs: Half-life is 18 ms, decays via β+ (positron emission) and proton emission.
    • $^{114}$Cs: Half-life is 570 ms, decays via β+ (positron emission).
    • $^{115}$Cs: Half-life is 1.4 s, decays via β+ (positron emission).
    • $^{116}$Cs: Half-life is 3.3 s, decays via β+ (positron emission).
    • $^{117}$Cs: Half-life is 8.4 s, decays via β+ (positron emission).
    • $^{118}$Cs: Half-life is 14 s, decays via β+ (positron emission).
    • $^{119}$Cs: Half-life is 43 s, decays via β+ (positron emission).
    • $^{120}$Cs: Half-life is 64 s, decays via β+ (positron emission).
    • $^{121}$Cs: Half-life is 2.0 min, decays via β+ (positron emission).
    • $^{122}$Cs: Half-life is 21 min, decays via β+ (positron emission).
    • $^{123}$Cs: Half-life is 5.8 min, decays via β+ (positron emission).
    • $^{124}$Cs: Half-life is 30.9 min, decays via β+ (positron emission).
    • $^{125}$Cs: Half-life is 45.4 min, decays via β+ (positron emission).
    • $^{126}$Cs: Half-life is 1.64 min, decays via β+ (positron emission).
    • $^{127}$Cs: Half-life is 6.25 h, decays via β+ (positron emission) and electron capture.
    • $^{128}$Cs: Half-life is 3.62 min, decays via β+ (positron emission).
    • $^{129}$Cs: Half-life is 32.06 h, decays via electron capture.
    • $^{130}$Cs: Half-life is 29.2 min, decays via β+ (positron emission) and electron capture.
    • $^{131}$Cs: Half-life is 9.689 d, decays via electron capture.
    • $^{132}$Cs: Half-life is 6.479 d, decays via β+ (positron emission), electron capture, and β− (beta decay).
    • $^{133}$Cs: Stable.
    • $^{134}$Cs: Half-life is 2.065 y, decays via β− (beta decay) and electron capture.
    • $^{135}$Cs: Half-life is 2.3 x 106 y, decays via β− (beta decay).
    • $^{136}$Cs: Half-life is 13.16 d, decays via β− (beta decay).
    • $^{137}$Cs: Half-life is 30.07 y, decays via β− (beta decay).
    • $^{138}$Cs: Half-life is 33.41 min, decays via β− (beta decay).
    • $^{139}$Cs: Half-life is 9.27 min, decays via β− (beta decay).
    • $^{140}$Cs: Half-life is 63.7 s, decays via β− (beta decay) and neutron emission.
    • $^{141}$Cs: Half-life is 24.9 s, decays via β− (beta decay) and neutron emission.
    • $^{142}$Cs: Half-life is 1.68 s, decays via β− (beta decay) and neutron emission.
    • $^{143}$Cs: Half-life is 1.78 s, decays via β− (beta decay) and neutron emission.

Barium (Ba)

  • Atomic Number: 56
  • Symbol: Ba
  • Isotopes:
    • $^{114}$Ba: Half-life is 430 ms, decays via β+ (positron emission) and alpha decay.
    • $^{115}$Ba: Half-life is 500 ms, decays via β+ (positron emission).
    • $^{116}$Ba: Half-life is 1.4 s, decays via β+ (positron emission).
    • $^{117}$Ba: Half-life is 1.75 s, decays via β+ (positron emission).
    • $^{118}$Ba: Half-life is 5.2 s, decays via β+ (positron emission).
    • $^{119}$Ba: Half-life is 5.4 s, decays via β+ (positron emission).
    • $^{120}$Ba: Half-life is 24 s, decays via β+ (positron emission).
    • $^{121}$Ba: Half-life is 29.7 s, decays via β+ (positron emission).
    • $^{122}$Ba: Half-life is 1.95 min, decays via β+ (positron emission).
    • $^{123}$Ba: Half-life is 2.74 min, decays via β+ (positron emission).
    • $^{124}$Ba: Half-life is 11.8 min, decays via β+ (positron emission).
    • $^{125}$Ba: Half-life is 3.5 min, decays via β+ (positron emission).
    • $^{126}$Ba: Half-life is 100 min, decays via β+ (positron emission) and electron capture.
    • $^{127}$Ba: Half-life is 12.7 min, decays via β+ (positron emission) and electron capture.
    • $^{128}$Ba: Half-life is 2.43 d, decays via electron capture.
    • $^{129}$Ba: Half-life is 2.23 h, decays via β+ (positron emission).
    • $^{130}$Ba: Stable.
    • $^{131}$Ba: Half-life is 11.5 d, decays via β+ (positron emission) and electron capture.
    • $^{132}$Ba: Stable.
    • $^{133}$Ba: Half-life is 10.51 y, decays via electron capture.
    • $^{134}$Ba: Stable.
    • $^{135}$Ba: Stable.
    • $^{136}$Ba: Stable.
    • $^{137}$Ba: Stable.
    • $^{138}$Ba: Stable.
    • $^{139}$Ba: Half-life is 83.1 min, decays via β− (beta decay).
    • $^{140}$Ba: Half-life is 12.75 d, decays via β− (beta decay).
    • $^{141}$Ba: Half-life is 18.27 min, decays via β− (beta decay).
    • $^{142}$Ba: Half-life is 10.6 min, decays via β− (beta decay).
    • $^{143}$Ba: Half-life is 14.7 s, decays via β− (beta decay) and neutron emission.
    • $^{144}$Ba: Half-life is 11.5 s, decays via β− (beta decay) and neutron emission.
    • $^{145}$Ba: Half-life is 4.3 s, decays via β− (beta decay) and neutron emission.
    • $^{146}$Ba: Half-life is 2.22 s, decays via β− (beta decay) and neutron emission.

Lanthanum (La)

  • Atomic Number: 57
  • Symbol: La
  • Isotopes:
    • $^{117}$La: Half-life is 22 ms, decays via proton emission and β+ (positron emission).
    • $^{118}$La: Half-life is 1.5 s, decays via β+ (positron emission).
    • $^{119}$La: Half-life is 1.2 s, decays via β+ (positron emission).
    • $^{120}$La: Half-life is 2.8 s, decays via β+ (positron emission).
    • $^{121}$La: Half-life is 5.3 s, decays via β+ (positron emission).
    • $^{122}$La: Half-life is 8.6 s, decays via β+ (positron emission).
    • $^{123}$La: Half-life is 16.6 s, decays via β+ (positron emission).
    • $^{124}$La: Half-life is 29.2 s, decays via β+ (positron emission).
    • $^{125}$La: Half-life is 64.8 s, decays via β+ (positron emission).
    • $^{126}$La: Half-life is 1.14 min, decays via β+ (positron emission).
    • $^{127}$La: Half-life is 4.8 min, decays via β+ (positron emission).
    • $^{128}$La: Half-life is 5.1 min, decays via β+ (positron emission) and electron capture.
    • $^{129}$La: Half-life is 11.6 min, decays via β+ (positron emission) and electron capture.
    • $^{130}$La: Half-life is 8.7 min, decays via β+ (positron emission) and electron capture.
    • $^{131}$La: Half-life is 59 min, decays via β+ (positron emission).
    • $^{132}$La: Half-life is 4.8 h, decays via β+ (positron emission) and electron capture.
    • $^{133}$La: Half-life is 3.9 h, decays via β+ (positron emission).
    • $^{134}$La: Half-life is 6.67 min, decays via β+ (positron emission) and electron capture.
    • $^{135}$La: Half-life is 1.83 h, decays via β+ (positron emission).
    • $^{136}$La: Half-life is 1.48 min, decays via β+ (positron emission) and electron capture.
    • $^{137}$La: Half-life is 6.0 x 104 y, decays via electron capture.
    • $^{138}$La: Half-life is 1.05 x 1011 y, decays via electron capture and β− (beta decay).
    • $^{139}$La: Stable.
    • $^{140}$La: Half-life is 40.27 h, decays via β− (beta decay).
    • $^{141}$La: Half-life is 3.92 h, decays via β− (beta decay).
    • $^{142}$La: Half-life is 91.1 s, decays via β− (beta decay) and neutron emission.
    • $^{143}$La: Half-life is 14.2 min, decays via β− (beta decay).
    • $^{144}$La: Half-life is 40.5 s, decays via β− (beta decay) and neutron emission.

Cerium (Ce)

  • Atomic Number: 58
  • Symbol: Ce
  • Isotopes:
    • $^{121}$Ce: Half-life is 1.2 s, decays via β+ (positron emission).
    • $^{122}$Ce: Half-life is 2.0 s, decays via β+ (positron emission).
    • $^{123}$Ce: Half-life is 3.8 s, decays via β+ (positron emission).
    • $^{124}$Ce: Half-life is 11.2 s, decays via β+ (positron emission).
    • $^{125}$Ce: Half-life is 21 s, decays via β+ (positron emission).
    • $^{126}$Ce: Half-life is 51 s, decays via β+ (positron emission).
    • $^{127}$Ce: Half-life is 3.8 min, decays via β+ (positron emission).
    • $^{128}$Ce: Half-life is 3.6 min, decays via β+ (positron emission).
    • $^{129}$Ce: Half-life is 3.12 min, decays via β+ (positron emission).
    • $^{130}$Ce: Half-life is 22.2 min, decays via β+ (positron emission).
    • $^{131}$Ce: Half-life is 29 min, decays via β+ (positron emission).
    • $^{132}$Ce: Half-life is 3.51 h, decays via electron capture.
    • $^{133}$Ce: Half-life is 97 min, decays via β+ (positron emission) and electron capture.
    • $^{134}$Ce: Half-life is 3.16 d, decays via electron capture.
    • $^{135}$Ce: Half-life is 17.7 h, decays via β+ (positron emission) and electron capture.
    • $^{136}$Ce: Stable.
    • $^{137}$Ce: Half-life is 9.0 h, decays via β+ (positron emission) and electron capture.
    • $^{138}$Ce: Stable.
    • $^{139}$Ce: Half-life is 137.6 d, decays via electron capture.
    • $^{140}$Ce: Stable.
    • $^{141}$Ce: Half-life is 32.50 d, decays via β− (beta decay).
    • $^{142}$Ce: Stable.
    • $^{143}$Ce: Half-life is 33.03 h, decays via β− (beta decay).
    • $^{144}$Ce: Half-life is 284.91 d, decays via β− (beta decay).
    • $^{145}$Ce: Half-life is 2.5 min, decays via β− (beta decay) and neutron emission.
    • $^{146}$Ce: Half-life is 13.5 min, decays via β− (beta decay).
    • $^{147}$Ce: Half-life is 56.4 s, decays via β− (beta decay) and neutron emission.
    • $^{148}$Ce: Half-life is 28.2 s, decays via β− (beta decay) and neutron emission.
    • $^{149}$Ce: Half-life is 5.3 s, decays via β− (beta decay) and neutron emission.
    • $^{150}$Ce: Half-life is 4.0 s, decays via β− (beta decay) and neutron emission.
    • $^{151}$Ce: Half-life is 1.2 s, decays via β− (beta decay) and neutron emission.
    • $^{152}$Ce: Half-life is 0.9 s, decays via β− (beta decay) and neutron emission.

Praseodymium (Pr)

  • Atomic Number: 59
  • Symbol: Pr
  • Isotopes:
    • $^{124}$Pr: Half-life is 1.2 s, decays via β+ (positron emission).
    • $^{125}$Pr: Half-life is 3.3 s, decays via β+ (positron emission).
    • $^{126}$Pr: Half-life is 3.1 s, decays via β+ (positron emission).
    • $^{127}$Pr: Half-life is 4.0 s, decays via β+ (positron emission).
    • $^{128}$Pr: Half-life is 6.8 s, decays via β+ (positron emission).
    • $^{129}$Pr: Half-life is 15.0 s, decays via β+ (positron emission).
    • $^{130}$Pr: Half-life is 40 s, decays via β+ (positron emission).
    • $^{131}$Pr: Half-life is 1.2 min, decays via β+ (positron emission).
    • $^{132}$Pr: Half-life is 1.5 min, decays via β+ (positron emission).
    • $^{133}$Pr: Half-life is 3.1 min, decays via β+ (positron emission).
    • $^{134}$Pr: Half-life is 11 min, decays via β+ (positron emission) and electron capture.
    • $^{135}$Pr: Half-life is 24 min, decays via β+ (positron emission).
    • $^{136}$Pr: Half-life is 13.1 min, decays via β+ (positron emission) and electron capture.
    • $^{137}$Pr: Half-life is 1.35 h, decays via β+ (positron emission).
    • $^{138}$Pr: Half-life is 1.45 min, decays via β+ (positron emission) and electron capture.
    • $^{139}$Pr: Half-life is 4.41 h, decays via β+ (positron emission).
    • $^{140}$Pr: Half-life is 3.39 min, decays via β+ (positron emission) and electron capture.
    • $^{141}$Pr: Stable.
    • $^{142}$Pr: Half-life is 19.12 h, decays via β− (beta decay).
    • $^{143}$Pr: Half-life is 13.57 d, decays via β− (beta decay).
    • $^{144}$Pr: Half-life is 17.28 min, decays via β− (beta decay).
    • $^{145}$Pr: Half-life is 5.98 h, decays via β− (beta decay).
    • $^{146}$Pr: Half-life is 24.15 min, decays via β− (beta decay) and neutron emission.
    • $^{147}$Pr: Half-life is 12.2 min, decays via β− (beta decay) and neutron emission.
    • $^{148}$Pr: Half-life is 2.29 min, decays via β− (beta decay) and neutron emission.
    • $^{149}$Pr: Half-life is 2.26 min, decays via β− (beta decay) and neutron emission.

Neodymium (Nd)

  • Atomic Number: 60
  • Symbol: Nd
  • Isotopes:
    • $^{127}$Nd: Half-life is 1.8 s, decays via β+ (positron emission).
    • $^{128}$Nd: Half-life is 5.3 s, decays via β+ (positron emission).
    • $^{129}$Nd: Half-life is 8.8 s, decays via β+ (positron emission).
    • $^{130}$Nd: Half-life is 21 s, decays via β+ (positron emission).
    • $^{131}$Nd: Half-life is 33 s, decays via β+ (positron emission).
    • $^{132}$Nd: Half-life is 1.3 min, decays via β+ (positron emission).
    • $^{133}$Nd: Half-life is 5.0 min, decays via β+ (positron emission).
    • $^{134}$Nd: Half-life is 8.5 min, decays via β+ (positron emission).
    • $^{135}$Nd: Half-life is 12.4 min, decays via β+ (positron emission).
    • $^{136}$Nd: Half-life is 50.6 min, decays via β+ (positron emission).
    • $^{137}$Nd: Half-life is 3.85 min, decays via β+ (positron emission) and electron capture.
    • $^{138}$Nd: Half-life is 5.04 h, decays via β+ (positron emission).
    • $^{139}$Nd: Half-life is 29.7 min, decays via β+ (positron emission) and electron capture.
    • $^{140}$Nd: Half-life is 3.37 d, decays via electron capture.
    • $^{141}$Nd: Half-life is 2.49 h, decays via β+ (positron emission).
    • $^{142}$Nd: Stable.
    • $^{143}$Nd: Stable.
    • $^{144}$Nd: Half-life is 2.29 x 1015 y, decays via alpha decay.
    • $^{145}$Nd: Stable.
    • $^{146}$Nd: Stable.
    • $^{147}$Nd: Half-life is 10.98 d, decays via β− (beta decay).
    • $^{148}$Nd: Stable.
    • $^{149}$Nd: Half-life is 1.72 h, decays via β− (beta decay).
    • $^{150}$Nd: Half-life is 7.9 x 1018 y, decays via double beta decay.
    • $^{151}$Nd: Half-life is 12.4 min, decays via β− (beta decay).
    • $^{152}$Nd: Half-life is 11.2 min, decays via β− (beta decay).
    • $^{153}$Nd: Half-life is 3.12 min, decays via β− (beta decay).
    • $^{154}$Nd: Half-life is 1.5 min, decays via β− (beta decay).
    • $^{155}$Nd: Half-life is 1.0 min, decays via β− (beta decay) and neutron emission.
    • $^{156}$Nd: Half-life is 600 ms, decays via β− (beta decay) and neutron emission.
    • $^{157}$Nd: Half-life is < 260 ns, decays via β− (beta decay) and neutron emission.

Master Isotope Table (Z = 1–118) – SolveForce Communications