Boron-13

Properties and data of the isotope ¹³B.

Content

General data

Name of the isotope:Boron-13; B-13Symbol:¹³B or 135BMass number A:13 (= number of nucleons)Atomic number Z:5 (= number of protons)Neutrons N:8Isotopic mass:13.0177800(11) u (atomic weight of Boron-13)Nuclide mass:13.0150371 u (calculated nuclear mass without electrons)Mass excess:16.56196 MeVMass defect:0.090664488 u (per nucleus)Nuclear binding energy:84.45342659 MeV (per nucleus)
6.49641743 MeV (average binding energy per nucleon)Separation energy:S_N = 4.8788(17) MeV (first neutron)
S_P = 15.8048(21) MeV (first proton)Half-life:17.33(17) msDecay constant λ:39.996952138485 s^-1Specific activity α:1.852825228816 × 10⁺²⁴ Bq g^-1
50076357535573 Ci g^-1Spin and parity:
(nuclear angular momentum)3/2-Isobaric spin: 3/2Magnetic dipole moment:μ(μ_N) = +3.1778(5)Quadrupole moment Q:+0.0365(8) barn (100 fm²)Nuclear g-factor:g_l = 2.1185333333333Mirror nucleus:Oxygen-13Year of discovery:1956

Radioactive Decay

Half-life T_½ = 17.33(17) ms respectively 1.733 × 10^-2 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	¹³C	99.72 %	13.4369(10) MeV
β^-, n	¹²C	0.286(37) %

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 8) and isobaric (same nucleon number A = 13) with Boron-13. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.