See also: List of individual Xenon isotopes (and general data sources).
General data
Name of the isotope:Xenon-138; Xe-138Symbol:138Xe or 13854XeMass number A:138 (= number of nucleons)Atomic number Z:54 (= number of protons)Neutrons N:84Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.5555555555556 (= neutron-proton ratio)Neutron excess (N-Z):30Isotopic mass:137.914146(3) u (atomic weight of Xenon-138)Nuclide mass:137.8845246 u (calculated nuclear mass without electrons)Mass excess:-79.97249 MeVMass defect:1.236258672 u (per nucleus)Nuclear binding energy:1151.56753542 MeV (per nucleus) 8.34469229 MeV (average binding energy per nucleon)Separation energy:SN = 5.6601(28) MeV (first neutron) SP = 10.905(9) MeV (first proton)Half-life:14.14(7) minDecay constant λ:0.00081700516331912 s-1Specific activity α:3.567523881962 × 10+18 Bq g-1 96419564.377362 Ci g-1Spin and parity: (nuclear angular momentum)0+Charge radius:4.8279(79) femtometer fmYear of discovery:1943
Radioactive Decay
Half-life T½ = 14.14(7) min (minutes) respectively 8.484 × 102 seconds s.
The following table shows the atomic nuclei that are isotonic (same neutron number N = 84) and isobaric (same nucleon number A = 138) with Xenon-138. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
