Magnesium-38

Properties and data of the isotope ³⁸Mg.

Contents

Magnesium-38 is a radioisotope of the chemical element magnesium, which has 26 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 38. The very short-lived, only artificially produced, unstable and thus radioactive nuclide has no practical significance; the study of ³⁸Mg is exclusively for academic purposes.

A report from 1997 describes the first observation of the neutron-rich isotope during irradiation of tantalum-181 with calcium-48 ions (70 MeV/nucleon) [1].

General data

Name of the isotope:Magnesium-38; Mg-38Symbol:³⁸Mg or 3812MgMass number A:38 (= number of nucleons)Atomic number Z:12 (= number of protons)Neutrons N:26Isotopic mass:38.03658(54) u (atomic weight of Magnesium-38)Nuclide mass:38.0299971 u (calculated nuclear mass without electrons)Mass excess:34.07405 MeVMass defect:0.2826082 u (per nucleus)Nuclear binding energy:263.24784265 MeV (per nucleus)
6.92757481 MeV (average binding energy per nucleon)Separation energy:S_N = 2.209(534) MeV (first neutron)
S_P = 26.349(851) MeV (first proton)Half-life:> 260 nsDecay constant λ:2665950.6944613 s^-1Specific activity α:4.224929107287 × 10⁺²⁸ Bq g^-1
1.141872731699 × 10⁺¹⁸ Ci g^-1Spin and parity:
(nuclear angular momentum)0+Year of discovery:1997

Radioactive Decay

Half-life T_½ = > 260 ns respectively 2.60 × 10^-7 seconds s.

Decay mode	Daughter	Probability	Decay energy
β^-	³⁸Al	100 %	17.60(53) MeV
β^-, n	³⁷Al	?	16.193(534) MeV
β^-, n	³⁶Al	?

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 26) and isobaric (same nucleon number A = 38) with Magnesium-38. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 26	Isobar A = 38
11	³⁷Na	³⁸Na
12	³⁸Mg	³⁸Mg
13	³⁹Al	³⁸Al
14	⁴⁰Si	³⁸Si
15	⁴¹P	³⁸P
16	⁴²S	³⁸S
17	⁴³Cl	³⁸Cl
18	⁴⁴Ar	³⁸Ar
19	⁴⁵K	³⁸K
20	⁴⁶Ca	³⁸Ca
21	⁴⁷Sc	³⁸Sc
22	⁴⁸Ti	³⁸Ti
23	⁴⁹V
24	⁵⁰Cr
25	⁵¹Mn
26	⁵²Fe
27	⁵³Co
28	⁵⁴Ni
29	⁵⁵Cu
30	⁵⁶Zn

External data and identifiers

Adopted Levels, Gammas:NuDat 38Mg

Literature and References

[1] - H. Sakurai, N. Aoi, D. Beaumel et al.:
Search for new neutron-rich nuclei with a 70A MeV ⁴⁸Ca beam.
In: Nuclear Physics A, 616, 1-2, (1997), DOI 10.1016/S0375-9474(97)00102-4.