Sulfur-42

Properties and data of the isotope ⁴²S.

Contents

General data

Name of the isotope:Sulfur-42; S-42Symbol:⁴²S or 4216SMass number A:42 (= number of nucleons)Atomic number Z:16 (= number of protons)Neutrons N:26Isotopic mass:41.981065(3) u (atomic weight of Sulfur-42)Nuclide mass:41.9722878 u (calculated nuclear mass without electrons)Mass excess:-17.63784 MeVMass defect:0.369423328 u (per nucleus)Nuclear binding energy:344.11561349 MeV (per nucleus)
8.19322889 MeV (average binding energy per nucleon)Separation energy:S_N = 6.70(5) MeV (first neutron)
S_P = 19.95(12) MeV (first proton)Half-life:1.016(15) sDecay constant λ:0.68223147692908 s^-1Specific activity α:1.002071720280 × 10⁺²² Bq g^-1
270830194670.38 Ci g^-1Spin and parity:
(nuclear angular momentum)0+Year of discovery:1979

Radioactive Decay

Half-life T_½ = 1.016(15) s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	⁴²Cl	> 96 %	7.23549 MeV
β^-, n	⁴¹Cl	< 4 %

Parent Nuclides

Direct parent isotopes are: ⁴²P, ⁴³P.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 26) and isobaric (same nucleon number A = 42) with Sulfur-42. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

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