Rubidium-82

Properties and data of the isotope ⁸²Rb.

Contents

Rubidium-82 is a radioisotope of the chemical element rubidium, which has 45 neutrons in its atomic nucleus in addition to the element-specific 37 protons; the sum of the number of these atomic nucleus building blocks results in a mass number of 82.

The discovery of the radioactive isotope during the irradiation of ammonium bromide templates with He ions of an energy of 20 to 100 MeV was reported in 1949 [1].

See also: List of individual Rubidium isotopes (and general data sources).

General data

Name of the isotope:Rubidium-82; Rb-82Symbol:⁸²Rb or 8237RbMass number A:82 (= number of nucleons)Atomic number Z:37 (= number of protons)Neutrons N:45Nucleon pairing (Z - N):odd - oddNuclear ratio (N/Z ratio):1.2162162162162 (= neutron-proton ratio)Neutron excess (N-Z):8Isotopic mass:81.918209(3) u (atomic weight of Rubidium-82)Nuclide mass:81.8979123 u (calculated nuclear mass without electrons)Mass excess:-76.18783 MeVMass defect:0.761238404 u (per nucleus)Nuclear binding energy:709.0890059 MeV (per nucleus)
8.6474269 MeV (average binding energy per nucleon)Separation energy:S_N = 8.802(6) MeV (first neutron)
S_P = 5.781(3) MeV (first proton)Half-life:1.2575(2) minDecay constant λ:0.0091868413593101 s^-1Specific activity α:6.753620773808 × 10⁺¹⁹ Bq g^-1
1825302911.84 Ci g^-1Spin and parity:
(nuclear angular momentum)1+Magnetic dipole moment:μ(μ_N) = +0.5545083(11)Quadrupole moment Q:+0.23(10) barn (100 fm²)Nuclear g-factor:g_l = 0.5545083Charge radius:4.2160(42) femtometer fmYear of discovery:1949

Radioactive Decay

Half-life T_½ = 1.2575(2) min (minutes) respectively 7.5450 × 10¹ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EC/β⁺	⁸²Kr	100 %	4.404(3) MeV

Parent Nuclides

Direct parent isotope is: ⁸²Sr.

Nuclear Isomers

Nuclear isomers or excited states with the activation energy in keV related to the ground state.

Nuclear Isomer	Excitation Energy	Half-life	Spin
^82mRb	69.0(15) keV	6.472(6) h	5-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 45) and isobaric (same nucleon number A = 82) with Rubidium-82. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 45	Isobar A = 82
23	⁶⁸V
25	⁷⁰Mn
26	⁷¹Fe
27	⁷²Co
28	⁷³Ni
29	⁷⁴Cu	⁸²Cu
30	⁷⁵Zn	⁸²Zn
31	⁷⁶Ga	⁸²Ga
32	⁷⁷Ge	⁸²Ge
33	⁷⁸As	⁸²As
34	⁷⁹Se	⁸²Se
35	⁸⁰Br	⁸²Br
36	⁸¹Kr	⁸²Kr
37	⁸²Rb	⁸²Rb
38	⁸³Sr	⁸²Sr
39	⁸⁴Y	⁸²Y
40	⁸⁵Zr	⁸²Zr
41	⁸⁶Nb	⁸²Nb
42	⁸⁷Mo	⁸²Mo
43	⁸⁸Tc
44	⁸⁹Ru
45	⁹⁰Rh
46	⁹¹Pd
47	⁹²Ag

External data and identifiers

Adopted Levels, Gammas:NuDat 82Rb

Literature and References

[1] - Frederick L. Reynolds, D. G. Karraker, D. H. Templeton:
Mass Spectrographic Assignment of Rubidium Isotopes.
In: Physical Review, 75, 313, (1949), DOI 10.1103/PhysRev.75.313.

[2] - Jean-François Chatal et al.:
Story of rubidium-82 and advantages for myocardial perfusion PET imaging.
In: Frontiers in Medicine, (2015), DOI 10.3389/fmed.2015.00065.