Boron-20

Properties and data of the isotope ²⁰B.

Contents

Boron-20 is a radioisotope of the chemical element boron, which has 15 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 20. The very short-lived, only artificially produced, unstable and thus radioactive nuclide has no practical significance; the study of ²⁰B is exclusively for academic purposes.

²⁰Boron was first artificially produced and characterized in 2018 [1].

General data

Name of the isotope:Boron-20; B-20Symbol:²⁰B or 205BMass number A:20 (= number of nucleons)Atomic number Z:5 (= number of protons)Neutrons N:15Isotopic mass:20.07451(59) u (atomic weight of Boron-20)Nuclide mass:20.0717671 u (calculated nuclear mass without electrons)Mass excess:69.40562 MeVMass defect:0.094588900000002 u (per nucleus)Nuclear binding energy:88.10899282 MeV (per nucleus)
4.40544964 MeV (average binding energy per nucleon)Half-life:< 260 nsDecay constant λ:2665950.6944613 s^-1Specific activity α:8.027365303846 × 10⁺²⁸ Bq g^-1
2.169558190228 × 10⁺¹⁸ Ci g^-1Spin and parity:
(nuclear angular momentum)(1-. 2-)Year of discovery:2018

Radioactive Decay

Half-life T_½ = < 260 ns respectively 2.6 × 10^-7 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
n	¹⁹B

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 15) and isobaric (same nucleon number A = 20) with Boron-20. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 15	Isobar A = 20
5	²⁰B	²⁰B
6	²¹C	²⁰C
7	²²N	²⁰N
8	²³O	²⁰O
9	²⁴F	²⁰F
10	²⁵Ne	²⁰Ne
11	²⁶Na	²⁰Na
12	²⁷Mg	²⁰Mg
13	²⁸Al	²⁰Al
14	²⁹Si
15	³⁰P
16	³¹S
17	³²Cl
18	³³Ar
19	³⁴K
20	³⁵Ca
21	³⁶Sc