Neon-31

Properties and data of the isotope ³¹Ne.

Contents

Neon-31 is a radioisotope of the chemical element neon, which has 21 neutrons in its atomic nucleus in addition to the element-specific 10 protons; the sum of the number of these atomic nucleus building blocks results in a mass number of 31. The very short-lived, only artificially produced, unstable and thus radioactive nuclide has no practical significance; the study of ³¹Ne is exclusively for academic purposes and experimental research.

The production and identification of the neutron-rich isotope was first reported in 1996. Neon-31 was observed as a fragment during irradiation of a tantalum-181 target with titanium-50 (80 MeV per nucleon) [1].

Neon-31 is one of the heaviest halo nuclei discovered so far [2]; based on the TODRHBc results of a study, an prolate one-neutron halo forms around the nearly spherical ³¹Ne nucleus [3].

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

General data

Name of the isotope:Neon-31; Ne-31Symbol:³¹Ne or 3110NeMass number A:31 (= number of nucleons)Atomic number Z:10 (= number of protons)Neutrons N:21Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):2.1 (= neutron-proton ratio)Neutron excess (N-Z):11Isotopic mass:31.033470(290) u (atomic weight of Neon-31)Nuclide mass:31.0279842 u (calculated nuclear mass without electrons)Mass excess:31.1771 MeVMass defect:0.226743556 u (per nucleus)Nuclear binding energy:211.21026195 MeV (per nucleus)
6.81323426 MeV (average binding energy per nucleon)Separation energy:S_N = 0.170(127) MeV (first neutron)
S_P = 25.068(567) MeV (first proton)Half-life:3.4(8) msDecay constant λ:203.86681781175 s^-1Specific activity α:3.960369979127 × 10⁺²⁴ Bq g^-1
1.070370264628 × 10⁺¹⁴ Ci g^-1Spin and parity:
(nuclear angular momentum)(3/2-)Year of discovery:1996

Radioactive Decay

Half-life T_½ = 3.4(8) ms respectively 3.4 × 10^-3 seconds s.

Decay mode	Daughter	Probability	Decay energy
β^-	³¹Na	100 %	18.94(27) MeV
β^-, n	³⁰Na	?	14.64(27) MeV
β^-, 2n	²⁹Na	?

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 21) and isobaric (same nucleon number A = 31) with Neon-31. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 21	Isobar A = 31
9	³⁰F	³¹F
10	³¹Ne	³¹Ne
11	³²Na	³¹Na
12	³³Mg	³¹Mg
13	³⁴Al	³¹Al
14	³⁵Si	³¹Si
15	³⁶P	³¹P
16	³⁷S	³¹S
17	³⁸Cl	³¹Cl
18	³⁹Ar	³¹Ar
19	⁴⁰K	³¹K
20	⁴¹Ca
21	⁴²Sc
22	⁴³Ti
23	⁴⁴V
24	⁴⁵Cr
25	⁴⁶Mn
26	⁴⁷Fe
27	⁴⁸Co
28	⁴⁹Ni

External data and identifiers

Adopted Levels, Gammas:NuDat 31Ne

Literature and References

[1] - H. Sakurai, N. Aoi, A. Goto et al.:
Production and identification of new neutron-rich nuclei, ³¹Ne and ³⁷Mg, in the reaction 80A MeV ⁵⁰Ti+¹⁸¹Ta.
In: Physical Review C, 54, R2802(R), (1996), DOI 10.1103/PhysRevC.54.R2802.

[2] - Juhee Hong, C. A. Bertulani, A. T. Kruppa:
Neutron removal from the deformed halo nucleus ³¹Ne.
In: Physical Review C, 96, 064603, (2017), DOI 10.1103/PhysRevC.96.064603.

[3] - Cong Pan, Kaiyuan Zhang, Shuangquan Zhang:
Nuclear magnetism in the deformed halo nucleus ³¹Ne.
In: Physics Letters B, 855, 138792, (2024), DOI 10.1016/j.physletb.2024.138792.