Argon-41

Properties and data of the isotope ⁴¹Ar.

Content

General data

Name of the isotope:Argon-41; Ar-41Symbol:⁴¹Ar or 4118ArMass number A:41 (= number of nucleons)Atomic number Z:18 (= number of protons)Neutrons N:23Isotopic mass:40.9645006(4) u (atomic weight of Argon-41)Nuclide mass:40.9546263 u (calculated nuclear mass without electrons)Mass excess:-33.06748 MeVMass defect:0.375643044 u (per nucleus)Nuclear binding energy:349.90924163 MeV (per nucleus)
8.53437175 MeV (average binding energy per nucleon)Separation energy:S_N = 6.0989(3) MeV (first neutron)
S_P = 12.80(3) MeV (first proton)Half-life:109.61(4) minDecay constant λ:0.00010539597672961 s^-1Specific activity α:1.586773544840 × 10⁺¹⁸ Bq g^-1
42885771.482184 Ci g^-1Spin and parity:
(nuclear angular momentum)7/2-Magnetic dipole moment:μ(μ_N) = -1.310(8)Nuclear g-factor:g_l = -0.37428571428571Mirror nucleus:Vanadium-41Year of discovery:1936

Radioactive Decay

Half-life T_½ = 109.61(4) min (minutes) respectively 6.5766 × 10³ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	⁴¹K	100 %	2.4920(3) MeV

Parent Nuclides

Direct parent isotope is: ⁴¹Cl.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 23) and isobaric (same nucleon number A = 41) with Argon-41. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 23	Isobar A = 41
10	³³Ne
11	³⁴Na
12	³⁵Mg
13	³⁶Al	⁴¹Al
14	³⁷Si	⁴¹Si
15	³⁸P	⁴¹P
16	³⁹S	⁴¹S
17	⁴⁰Cl	⁴¹Cl
18	⁴¹Ar	⁴¹Ar
19	⁴²K	⁴¹K
20	⁴³Ca	⁴¹Ca
21	⁴⁴Sc	⁴¹Sc
22	⁴⁵Ti	⁴¹Ti
23	⁴⁶V	⁴¹V
24	⁴⁷Cr	⁴¹Cr
25	⁴⁸Mn
26	⁴⁹Fe
27	⁵⁰Co
28	⁵¹Ni