Bismuth-215

Properties and data of the isotope ²¹⁵Bi.

Contents

Bismuth-215 is the radioisotope of the element Bismuth, whose atomic nucleus has 132 neutrons in addition to the element-specific 83 protons, resulting in a mass number of 215: ²¹⁵Bi.

General data

Name of the isotope:Bismuth-215; Bi-215Symbol:²¹⁵Bi or 21583BiMass number A:215 (= number of nucleons)Atomic number Z:83 (= number of protons)Neutrons N:132Isotopic mass:215.001749(6) u (atomic weight of Bismuth-215)Nuclide mass:214.9562221 u (calculated nuclear mass without electrons)Mass excess:1.62918 MeVMass defect:1.791497568 u (per nucleus)Nuclear binding energy:1668.76923561 MeV (per nucleus)
7.76171737 MeV (average binding energy per nucleon)Separation energy:S_N = 5.241(13) MeV (first neutron)
S_P = 5.477(6) MeV (first proton)Half-life:7.6(2) minDecay constant λ:0.0015200596064911 s^-1Specific activity α:4.25768049571 × 10⁺¹⁸ Bq g^-1
115072445.83016 Ci g^-1Spin and parity:
(nuclear angular momentum)(9/2-)Year of discovery:1953

Radioactive Decay

Half-life T_½ = 7.6(2) min (minutes) respectively 4.56 × 10² seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	²¹⁵Po	100 %	2.171(6) MeV

Parent Nuclides

Direct parent isotope is: ²¹⁹At.

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
^215mBi	1347+x keV	36.9(6) s	(25/2-)

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 132) and isobaric (same nucleon number A = 215) with Bismuth-215. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 132	Isobar A = 215
80	²¹²Hg	²¹⁵Hg
81	²¹³Tl	²¹⁵Tl
82	²¹⁴Pb	²¹⁵Pb
83	²¹⁵Bi	²¹⁵Bi
84	²¹⁶Po	²¹⁵Po
85	²¹⁷At	²¹⁵At
86	²¹⁸Rn	²¹⁵Rn
87	²¹⁹Fr	²¹⁵Fr
88	²²⁰Ra	²¹⁵Ra
89	²²¹Ac	²¹⁵Ac
90	²²²Th	²¹⁵Th
91	²²³Pa	²¹⁵Pa
92	²²⁴U	²¹⁵U
93	²²⁵Np