Arsenic-73

Properties and data of the isotope ⁷³As.

Contents

General Data

Radioactive Decay

Parent Nuclides

Isotones und Isobares

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

General data

Name of the isotope:Arsenic-73; As-73Symbol:⁷³As or 7333AsMass number A:73 (= number of nucleons)Atomic number Z:33 (= number of protons)Neutrons N:40Nucleon pairing (Z - N):odd - evenNuclear ratio (N/Z ratio):1.2121212121212 (= neutron-proton ratio)Neutron excess (N-Z):7Isotopic mass:72.923829(4) u (atomic weight of Arsenic-73)Nuclide mass:72.9057265 u (calculated nuclear mass without electrons)Mass excess:-70.95283 MeVMass defect:0.680993696 u (per nucleus)Nuclear binding energy:634.34154186 MeV (per nucleus)
8.68961016 MeV (average binding energy per nucleon)Separation energy:S_N = 10.794(6) MeV (first neutron)
S_P = 5.656(4) MeV (first proton)Half-life:80.30(6) dDecay constant λ:9.990705868040 × 10^-8 s^-1Specific activity α:8.356310837157 × 10⁺¹⁴ Bq g^-1
22584.62388421 Ci g^-1Spin and parity:
(nuclear angular momentum)3/2-Year of discovery:1948

Radioactive Decay

Half-life T_½ = 80.30(6) d respectively 6.937920 × 10⁶ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EC	⁷³Ge	100 %	0.345(4) MeV

Parent Nuclides

Direct parent isotope is: ⁷³Se.

Nuclear Isomers

Nuclear isomers or excited states with the activation energy in keV related to the ground state.

Nuclear Isomer	Excitation Energy	Half-life	Spin
^73mAs	427.902(21) keV	5.7(2) μs	9/2+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 40) and isobaric (same nucleon number A = 73) with Arsenic-73. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 40	Isobar A = 73
19	⁵⁹K
21	⁶¹Sc
22	⁶²Ti
23	⁶³V
24	⁶⁴Cr
25	⁶⁵Mn
26	⁶⁶Fe	⁷³Fe
27	⁶⁷Co	⁷³Co
28	⁶⁸Ni	⁷³Ni
29	⁶⁹Cu	⁷³Cu
30	⁷⁰Zn	⁷³Zn
31	⁷¹Ga	⁷³Ga
32	⁷²Ge	⁷³Ge
33	⁷³As	⁷³As
34	⁷⁴Se	⁷³Se
35	⁷⁵Br	⁷³Br
36	⁷⁶Kr	⁷³Kr
37	⁷⁷Rb	⁷³Rb
38	⁷⁸Sr	⁷³Sr
39	⁷⁹Y
40	⁸⁰Zr
41	⁸¹Nb
42	⁸²Mo