Yttrium-77

Properties and data of the isotope ⁷⁷Y.

Contents

General data

Name of the isotope:Yttrium-77; Y-77Symbol:⁷⁷Y or 7739YMass number A:77 (= number of nucleons)Atomic number Z:39 (= number of protons)Neutrons N:38Isotopic mass:76.95015(22) u (atomic weight of Yttrium-77)Nuclide mass:76.9287563 u (calculated nuclear mass without electrons)Mass excess:-46.43498 MeVMass defect:0.684293056 u (per nucleus)Nuclear binding energy:637.41487591 MeV (per nucleus)
8.27811527 MeV (average binding energy per nucleon)Separation energy:S_N = 16.03(36) MeV (first neutron)Half-life:57 msDecay constant λ:1.2160476851929 s^-1Specific activity α:9.635803227146 × 10⁺²¹ Bq g^-1
260427114247.21 Ci g^-1Spin and parity:
(nuclear angular momentum)(5/2+)Mirror nucleus:Strontium-77Year of discovery:1999

Radioactive Decay

Half-life T_½ = 57 ms respectively 5.7 × 10^-1 seconds s.

Decay mode	Daughter	Probability	Decay energy
p	⁷⁶Sr	> 99.9 %
EC/β⁺	⁷⁷Sr	< 0.1 %	11.36(20) MeV
EC, p		?

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 38) and isobaric (same nucleon number A = 77) with Yttrium-77. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

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