Magnesium-27

Properties and data of the isotope ²⁷Mg.

Contents

General Data

Radioactive Decay

Parent Nuclides

Isotones und Isobares

Literature

Magnesium-27 is a radioisotope of the chemical element magnesium, which has 15 neutrons in its atomic nucleus in addition to the element-specific 12 protons; the sum of the number of these atomic nucleus building blocks results in a mass number of 27. The very short-lived, only artificially produced, unstable and thus radioactive nuclide has no practical significance; the study of ²⁷Mg is exclusively for academic purposes.

According to a publication from 1934, magnesium-27 was first observed during the irradiation of an Al template with neutrons [1].

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

General data

Name of the isotope:Magnesium-27; Mg-27Symbol:²⁷Mg or 2712MgMass number A:27 (= number of nucleons)Atomic number Z:12 (= number of protons)Neutrons N:15Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.25 (= neutron-proton ratio)Neutron excess (N-Z):3Isotopic mass:26.98434065(5) u (atomic weight of Magnesium-27)Nuclide mass:26.9777577 u (calculated nuclear mass without electrons)Mass excess:-14.58659 MeVMass defect:0.239533474 u (per nucleus)Nuclear binding energy:223.12399383 MeV (per nucleus)
8.26385162 MeV (average binding energy per nucleon)Separation energy:S_N = 6.44337(4) MeV (first neutron)
S_P = 15.015(4) MeV (first proton)Half-life:9.458(12) minDecay constant λ:0.0012214477700711 s^-1Specific activity α:2.829127124778 × 10⁺¹⁹ Bq g^-1
764628952.64281 Ci g^-1Spin and parity:
(nuclear angular momentum)1/2+Magnetic dipole moment:μ(μ_N) = -0.4106(15)Nuclear g-factor:g_l = -0.8212Charge radius:0 femtometer fmMirror nucleus:Phosphorus-27Year of discovery:1934

Radioactive Decay

Half-life T_½ = 9.458(12) min (minutes) respectively 5.6748 × 10² seconds s.

Decay mode	Daughter	Probability	Decay energy	Details	γ energy (intensity)
β^-	²⁷Al	100 %	2.61027(7) MeV	β^-: 0.6463(3) MeV [29.06(9) %] β^-: 0.7248(3) MeV [70.94(9) %]	0.17082(10) MeV [0.86(2) %] 0.84376(10) MeV [71.80(2) %] 1.01452(10) MeV [28.20 %]

Parent Nuclides

Direct parent isotope is: ²⁷Na.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 15) and isobaric (same nucleon number A = 27) with Magnesium-27. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

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

External data and identifiers

Adopted Levels, Gammas:NuDat 27Mg

Literature and References

[1] - Enrico Fermi, Edoardo Amaldi, O. D'Agostino, F. Rasetti, E. Segrè:
Artificial radioactivity produced by neutron bombardment.
In: Proceedings of the Royal Society A, 146, 857, (1934), DOI 10.1098/rspa.1934.0168.

[2] - G. S. Zahn, F. A. Genezini:
Half-life determination for ²⁷Mg.
In: Journal of Physics: Conference Series, 630, 012011, (2015), DOI 10.1088/1742-6596/630/1/012011.

[3] - Mohammed Yahya Hadi, Ammar A. Al-Sa’ad:
Calculations of The Shell Model for 27Mg Isotope.
In: Journal of Kufa-Physics, 15(1), (2023), DOI 10.31257/2018/JKP/2023/v15.i01.11214.

[4] - A. I. Kilic:
Analysis of astrophysical ²⁶Mg(n,γ)²⁷Mg reaction via the asymptotic normalization coefficient method.
In: Modern Physics Letters A, 39(2), 2350188, (2024), DOI 10.1142/S0217732323501882.