Yttrium-87
Properties and data of the isotope 87Y.
See also: list of Yttrium isotopes.
General data
Name of the isotope:Yttrium-87; Y-87Symbol: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-87)Nuclide 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)Separation energy:SN = 11.807(14) MeV (first neutron)
SP = 5.7843(11) MeV (first proton)Half-life:79.8(3) hDecay constant λ:2.412793026176 × 10-6 s-1Specific activity α:1.689555752268 × 10+16 Bq g-1
456636.68980224 Ci g-1Spin and parity:
(nuclear angular momentum)1/2-Magnetic dipole moment:μ(μN) = - 0.19(2)Nuclear g-factor:gl = -0.38Charge radius:4.2498(22) femtometer fmYear of discovery:1940
Radioactive Decay
Half-life T½ = 79.8(3) h (hours) respectively 2.87280 × 105 seconds s.
Decay mode | Daughter | Probability | Decay energy | γ energy (intensity) |
---|
EC/β+ | 87Sr | 100 % | 1.8617(11) MeV | |
Parent Nuclides
Direct parent isotope is: 87Zr.
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 |
---|
87mY | 380.82(7) keV | 13.37(3) h | 9/2+ |
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-87. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
Z | 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 | |
External data and identifiers
Last update: 2020-10-14
Perma link: https://www.chemlin.org/isotope/yttrium-87
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