Aluminium-39

Properties and data of the isotope ³⁹Al.

Content

General data

Name of the isotope:Aluminium-39; Al-39Symbol:³⁹Al or 3913AlMass number A:39 (= number of nucleons)Atomic number Z:13 (= number of protons)Neutrons N:26Isotopic mass:39.02217(43) u (atomic weight of Aluminium-39)Nuclide mass:39.0150385 u (calculated nuclear mass without electrons)Mass excess:20.65122 MeVMass defect:0.304843232 u (per nucleus)Nuclear binding energy:283.95964155 MeV (per nucleus)
7.28101645 MeV (average binding energy per nucleon)Separation energy:S_N = 3.63(55) MeV (first neutron)
S_P = 20.71(64) MeV (first proton)Half-life:7.6(16) msDecay constant λ:91.203576389466 s^-1Specific activity α:1.408309702429 × 10⁺²⁴ Bq g^-1
38062424389976 Ci g^-1Spin and parity:
(nuclear angular momentum)(5/2+)Year of discovery:1989

Radioactive Decay

Half-life T_½ = 7.6(16) ms respectively 7.6 × 10^-3 seconds s.

Decay mode	Daughter	Probability	Decay energy
β^-	³⁹Si	100 %	18.33(42) MeV
β^-, n	³⁸Si	?	16.75(41) MeV
β^-, 2n	³⁷Si	?

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 26) and isobaric (same nucleon number A = 39) with Aluminium-39. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

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