Zirconium-78

Properties and data of the isotope ⁷⁸Zr.

Content

General data

Name of the isotope:Zirconium-78; Zr-78Symbol:⁷⁸Zr or 7840ZrMass number A:78 (= number of nucleons)Atomic number Z:40 (= number of protons)Neutrons N:38Isotopic mass:77.95615(43) u (atomic weight of Zirconium-78)Nuclide mass:77.9342078 u (calculated nuclear mass without electrons)Mass excess:-40.84601 MeVMass defect:0.686118088 u (per nucleus)Nuclear binding energy:639.11488226 MeV (per nucleus)
8.19378054 MeV (average binding energy per nucleon)Separation energy:S_N = 16.88(56) MeV (first neutron)
S_P = 1.70(45) MeV (first proton)Half-life:170 nsDecay constant λ:4077336.356235 s^-1Specific activity α:3.188869333842 × 10⁺²⁸ Bq g^-1
8.618565767142 × 10⁺¹⁷ Ci g^-1Spin and parity:
(nuclear angular momentum)0+Mirror nucleus:Strontium-78Year of discovery:2001

Radioactive Decay

Half-life T_½ = 170 ns respectively 1.70 × 10^-7 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EE/β⁺	⁷⁸Y	?	11.32(50) MeV

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 38) and isobaric (same nucleon number A = 78) with Zirconium-78. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 38	Isobar A = 78
20	⁵⁸Ca
21	⁵⁹Sc
22	⁶⁰Ti
23	⁶¹V
24	⁶²Cr
25	⁶³Mn
26	⁶⁴Fe
27	⁶⁵Co
28	⁶⁶Ni	⁷⁸Ni
29	⁶⁷Cu	⁷⁸Cu
30	⁶⁸Zn	⁷⁸Zn
31	⁶⁹Ga	⁷⁸Ga
32	⁷⁰Ge	⁷⁸Ge
33	⁷¹As	⁷⁸As
34	⁷²Se	⁷⁸Se
35	⁷³Br	⁷⁸Br
36	⁷⁴Kr	⁷⁸Kr
37	⁷⁵Rb	⁷⁸Rb
38	⁷⁶Sr	⁷⁸Sr
39	⁷⁷Y	⁷⁸Y
40	⁷⁸Zr	⁷⁸Zr