Boron-13

Properties and data of the isotope ¹³B.

Contents

Boron-13 is a radioisotope of the chemical element boron, which has 8 neutrons in its atomic nucleus in addition to the element-specific 5 protons; the sum of the number of these atomic nucleus building blocks results in a mass number of 13. The very short-lived, only artificially produced, unstable and thus radioactive nuclide has no practical significance; the study of ¹³B is exclusively for academic purposes.

The discovery of boron-13 was first reported in 1956; the nuclide was produced by the following nuclear reaction with a 1.16 MeV beam of lithium-7:

⁷Li(⁷Li,p)¹³B [1].

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(22) MeV (first proton)Half-life:17.16(18) msDecay constant λ:40.393192340323 s^-1Specific activity α:1.871180723507 × 10⁺²⁴ Bq g^-1
50572451986684 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 = 17.16(18) ms respectively 1.716 × 10^-2 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	¹³C	99.734(36) %	13.4369(10) MeV
β^-, n	¹²C	0.266(36) %

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.

Z	Isotone N = 8	Isobar A = 13
2	¹⁰He
3	¹¹Li	¹³Li
4	¹²Be	¹³Be
5	¹³B	¹³B
6	¹⁴C	¹³C
7	¹⁵N	¹³N
8	¹⁶O	¹³O
9	¹⁷F	¹³F
10	¹⁸Ne
11	¹⁹Na
12	²⁰Mg
13	²¹Al
14	²²Si

External data and identifiers

Adopted Levels, Gammas:NuDat 13B

Literature and References

[1] - S. K. Allison, P. G. Murphy, E. Norbeck, Jr.:
Mass of B¹³ from the Nuclear Reaction Li⁷⁢(Li⁷,p)B⁢¹³.
In: Physical Review, 102, 1182, (1956), DOI 10.1103/PhysRev.102.1182.2.

[2] - R. Kalpakchieva, H.G. Bohlen, W. von Oertzen et al.:
Spectroscopy of ¹³B, ¹⁴B, ¹⁵B and ¹⁶B using multi-nucleon transfer reactions.
In: The European Physical Journal A - Hadrons and Nuclei, 7, (2000), DOI 10.1007/PL00013641.