Bromine-80

Properties and data of the isotope ⁸⁰Br.

Contents

Bromine-80 is a radioisotope of the chemical element bromine, which has 45 neutrons in its atomic nucleus in addition to the element-specific 35 protons; the sum of the number of these atomic nucleus building blocks results in a mass number of 80.

A report on the discovery of the radioactive isotope appeared in 1937 [1]: According to this report, bromine-80 could be produced and observed by irradiating natural bromine samples with gamma rays of an energy of 17.5 MeV. The isotope was initially formed from bromine-81 according to the radionuclear reaction:

⁸¹Br(γ,n)⁸⁰Br.

The neutrons released in this reaction could then react with the bromine-79 present in the sample to form bromine-80:

⁷⁹Br(n,γ)⁸⁰Br.

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

General data

Name of the isotope:Bromine-80; Br-80Symbol:⁸⁰Br or 8035BrMass number A:80 (= number of nucleons)Atomic number Z:35 (= number of protons)Neutrons N:45Nucleon pairing (Z - N):odd - oddNuclear ratio (N/Z ratio):1.2857142857143 (= neutron-proton ratio)Neutron excess (N-Z):10Isotopic mass:79.9185298(11) u (atomic weight of Bromine-80)Nuclide mass:79.8993302 u (calculated nuclear mass without electrons)Mass excess:-75.889 MeVMass defect:0.74526754 u (per nucleus)Nuclear binding energy:694.2122419 MeV (per nucleus)
8.67765302 MeV (average binding energy per nucleon)Separation energy:S_N = 7.89228(13) MeV (first neutron)
S_P = 7.2605(10) MeV (first proton)Half-life:17.68(2) minDecay constant λ:0.00065341928785817 s^-1Specific activity α:4.98099112921 × 10⁺¹⁸ Bq g^-1
134621381.87073 Ci g^-1Spin and parity:
(nuclear angular momentum)1+Magnetic dipole moment:μ(μ_N) = 0.5140(6)Quadrupole moment Q:+0.182(3) barn (100 fm²)Nuclear g-factor:g_l = 0.514Year of discovery:1937

Radioactive Decay

Half-life T_½ = 17.68(2) min (minutes) respectively 1.0608 × 10³ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EC/β⁺	⁸⁰Se	8.3(2) %	1.8705(14) MeV
β^-	⁸⁰Kr	91.7(2) %	2.0044(11) MeV

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
^80mBr	85.843(4) keV	4.4205(8) 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 = 80) with Bromine-80. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

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