Yttrium-87m

Properties and data of the isotope ⁸⁷Y.

Content

General data

Name of the isotope:Yttrium-87m; Y-87mSymbol:⁸⁷Y or 8739YMass number A:87 (= number of nucleons)Atomic number Z:39 (= number of protons)Neutrons N:48Isotopic mass:86.9108761(12) u (atomic weight of Yttrium-87m)
Excitation energy: 380.82(7) keVNuclide mass:86.8894824 u (calculated nuclear mass without electrons)Mass excess:-83.01838 MeVMass defect:0.81021611600001 u (per nucleus)Nuclear binding energy:754.71145076 MeV (per nucleus)
8.67484426 MeV (average binding energy per nucleon)Half-life:13.37(3) hDecay constant λ:1.440096361173 × 10^-5 s^-1Specific activity α:1.0084259463 × 10⁺¹⁷ Bq g^-1
2725475.5307568 Ci g^-1Spin and parity:
(nuclear angular momentum)9/2+Magnetic dipole moment:μ(μ_N) = + 6.24(2)Quadrupole moment Q:-0.50(6) barn (100 fm²)Nuclear g-factor:g_l = 1.3866666666667

Radioactive Decay

Half-life T_½ = 13.37(3) h (hours) respectively 4.8132 × 10⁴ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
Iso	⁸⁷Y	98.43(11) %
EE/β⁺	⁸⁷Sr	1.57(11) %

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
⁸⁷Y		79.8(3) h	1/2-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 48) and isobaric (same nucleon number A = 87) with Yttrium-87m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 48	Isobar A = 87
26	⁷⁴Fe
27	⁷⁵Co
28	⁷⁶Ni
29	⁷⁷Cu
30	⁷⁸Zn
31	⁷⁹Ga	⁸⁷Ga
32	⁸⁰Ge	⁸⁷Ge
33	⁸¹As	⁸⁷As
34	⁸²Se	⁸⁷Se
35	⁸³Br	⁸⁷Br
36	⁸⁴Kr	⁸⁷Kr
37	⁸⁵Rb	⁸⁷Rb
38	⁸⁶Sr	⁸⁷Sr
39	⁸⁷Y	⁸⁷Y
40	⁸⁸Zr	⁸⁷Zr
41	⁸⁹Nb	⁸⁷Nb
42	⁹⁰Mo	⁸⁷Mo
43	⁹¹Tc	⁸⁷Tc
44	⁹²Ru	⁸⁷Ru
45	⁹³Rh
46	⁹⁴Pd
47	⁹⁵Ag
48	⁹⁶Cd
49	⁹⁷In