Periodic Table of Elements

Cs - Cesium

Cesium Menu

Nuclides / Isotopes

SpinHalf LifeDMDTBR
Cs112111.9557Syn 500us    
 0.57sε + PI11379.300
 0.57sε + αTe1100.1615.300
Cs115114.93660Syn 1.4sε + PI114~0.075.800
 1.4sεXe115 8.800
Cs116115.93361Syn>4+3.84sεXe116 10.500
meta state 0.000MeVSyn1+0.7sεXe116 10.500
meta state 0.000MeVSyn1+0.7sε + αTe112>012.400
 0.7sε + PI115>06.700
Cs117116.928662Syn9/2+8.4sεXe117 7.520
meta state 0.150MeVSyn3/2+6.5sεXe117 7.670
Cs118117.926663Syn214sε + PI117<0.044.730
 14sε + αTe114<0.002411.080
 14sεXe118 9.300
meta state 0.000MeVSyn7-17sε + PI117<0.044.730
 17sε + αTe114<0.002411.080
 17sεXe118 9.300
Cs119118.922464Syn9/2+43sεXe119 6.330
meta state 0.000MeVSyn3/2+30.4sεXe119 6.330
Cs120119.920765Syn264sεXe120 7.920
 64sε + PI119 2.470
meta state 0.000MeVSyn 57sεXe120 7.920
Cs121120.917266Syn3/2+155sεXe121 5.400
meta state 0.068MeVSyn9/2+122sεXe121835.468
 122sIT 170.068
Cs122121.916167Syn1+21sεXe122 7.050
meta state 0.076MeVSyn8-3.7mεXe122 7.126
meta state 0.127MeVSyn5-0.36sIT  0.127
Cs123122.91368Syn1/2+5.94mεXe123 4.200
meta state 0.157MeVSyn11/2-1.64sIT  0.157
Cs124123.912269Syn1+30.8sεXe124 5.915
meta state 0.462MeVSyn7+6.3sIT  0.463
Cs125124.909770Syn1/2+45mεXe125 3.092
Cs126125.909471Syn1+1.64mεXe126 4.826
Cs127126.907472Syn1/2+6.25hεXe127 2.085
Cs128127.907873Syn1+3.66mεXe128 3.930
Cs129128.906174Syn1/2+32.06hεXe129 1.196
meta state 0.163MeVSyn5-3.46mIT 99.840.163
Cs131130.905576Syn5/2+9.689dεXe131 0.352
 2.0648yβ-Ba134 2.059
meta state 0.139MeVSyn8-2.903hIT  0.139
Cs135134.90680Syn7/2+2300000yβ-Ba135 0.269
meta state 1.633MeVSyn19/2-53mIT  1.633
Cs136135.907381Syn5+13.16dβ-Ba136 2.548
meta state 0.000MeVSyn8-19sITCs136>0 
 19sβ-Ba136 2.548
Cs137136.907182Syn7/2+30.07yβ-Ba137 1.176
Cs138137.91183Syn3-33.41mβ-Ba138 5.373
meta state 0.080MeVSyn6-2.91mIT 810.080
Cs139138.913484Syn7/2+9.27mβ-Ba139 4.213
Cs140139.917385Syn1-63.7sβ-Ba140 6.219
Cs141140.9286Syn7/2+24.94sβ- + NBa1400.030.735
 24.94sβ-Ba141 5.255
Cs142141.924387Syn0-1.7sβ- + NBa1410.091.137
 1.7sβ-Ba142 7.306
Cs143142.927388Syn3/2+1.78sβ- + NBa1421.622.048
 1.78sβ-Ba143 6.243
Cs144143.93289Syn11.01sβ- + NBa1433.22.560
 1.01sβ-Ba144 8.465
meta state 0.000MeVSyn <1sβ-Ba144 8.465
Cs145144.935490Syn3/2+0.594sβ- + NBa14414.33.550
 0.594sβ-Ba145 7.890
Cs146145.940291Syn1-0.321sβ- + NBa14514.24.320
 0.321sβ-Ba146 9.380
Cs147146.94492Syn3/2+0.225sβ- + NBa14628.54.740
 0.225sβ-Ba147 9.250
Cs148147.94993Syn 158msβ- + NBa14725.110.500
 158msβ-Ba148 10.500
Cs149148.95394Syn >50ms    
Cs150149.95895Syn >50ms    
NuclidePotential Parent Nuclides
Cs112None known
Cs113None known
Cs114Ba114 (Syn)
Cs115Ba115 (Syn)
Cs116Ba116 (Syn)
meta state 0.000MeVNone known
meta state 0.000MeVNone known
Cs117Ba117 (Syn)
meta state 0.150MeVNone known
Cs118Ba118 (Syn)
meta state 0.000MeVNone known
Cs119Ba119 (Syn) La120 (Syn)
meta state 0.000MeVNone known
Cs120Ba120 (Syn)
meta state 0.000MeVNone known
Cs121Ba121 (Syn) La122 (Syn)
meta state 0.068MeVNone known
Cs122Ba122 (Syn)
meta state 0.076MeVNone known
meta state 0.127MeVNone known
Cs123Ba123 (Syn)
meta state 0.157MeVNone known
Cs124Ba124 (Syn)
meta state 0.462MeVNone known
Cs125Ba125 (Syn)
Cs126Ba126 (Syn)
Cs127Ba127 (Syn)
Cs128Ba128 (Syn)
Cs129Ba129 (Syn) Ba129m (Syn)
Cs130None known
meta state 0.163MeVNone known
Cs131Ba131 (Syn)
Cs132None known
Cs133Ba133 (Syn) Ba133m (Syn) Xe133 (Syn)
Cs134None known
meta state 0.139MeVNone known
Cs135Xe135 (Syn) Xe135m (Syn)
meta state 1.633MeVNone known
Cs136Cs136m (Syn)
meta state 0.000MeVNone known
Cs137Xe137 (Syn)
Cs138Xe138 (Syn)
meta state 0.080MeVNone known
Cs139Xe139 (Syn)
Cs140Xe140 (Syn) Xe141 (Syn)
Cs141Xe141 (Syn) Xe142 (Syn)
Cs142Xe142 (Syn)
Cs143Xe143 (Syn)
Cs144Xe144 (Syn) Xe145 (Syn)
meta state 0.000MeVNone known
Cs145Xe145 (Syn)
Cs146None known
Cs147None known
Cs148None known
Cs149None known
Cs150None known
Cs151None known


  • NN = Number of Neutrons
  • Abun % = Natural Abundance (as a percentage)
  • Syn = Synthetic Nuclide (does not occur in nature)
  • DM = Decay Mode
    α = Alpha emission
    β- = Beta emission
    β- β- = Double beta decay
    β+ = Positron emission
    ε = Electron Capture
    IT = Isomeric Transition
    N = Neutron emission
    P = Proton emission
    SF = Spontaneous Fission
  • DT = Decays To
  • BR % = Branch Ratio (as a percentage)

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