¹⁸⁴Bi — Unstable · t½ ≈ 6.0 ms · Decay: α → ¹⁸⁰Tl · Type: synthetic · Uses: research.
¹⁸⁵Bi — Unstable · t½ ≈ 10.0 ms · Decay: α → ¹⁸¹Tl · Type: synthetic · Uses: research.
¹⁸⁶Bi — Unstable · t½ ≈ 15.0 ms · Decay: α → ¹⁸²Tl · Type: synthetic · Uses: research.
¹⁸⁷Bi — Unstable · t½ ≈ 30.0 ms · Decay: α → ¹⁸³Tl · Type: synthetic · Uses: research.
¹⁸⁸Bi — Unstable · t½ ≈ 46.0 ms · Decay: α → ¹⁸⁴Tl · Type: synthetic · Uses: research.
¹⁸⁹Bi — Unstable · t½ ≈ 0.5 s · Decay: α → ¹⁸⁵Tl · Type: synthetic · Uses: research.
¹⁹⁰Bi — Unstable · t½ ≈ 1.3 s · Decay: α → ¹⁸⁶Tl · Type: synthetic · Uses: research.
¹⁹¹Bi — Unstable · t½ ≈ 2.0 s · Decay: α → ¹⁸⁷Tl · Type: synthetic · Uses: research.
¹⁹²Bi — Unstable · t½ ≈ 2.5 s · Decay: α → ¹⁸⁸Tl · Type: synthetic · Uses: research.
¹⁹³Bi — Unstable · t½ ≈ 3.0 s · Decay: α → ¹⁸⁹Tl · Type: synthetic · Uses: research.
¹⁹⁴Bi — Unstable · t½ ≈ 3.9 s · Decay: α → ¹⁹⁰Tl · Type: synthetic · Uses: research.
¹⁹⁵Bi — Unstable · t½ ≈ 7.0 s · Decay: α → ¹⁹¹Tl · Type: synthetic · Uses: research.
¹⁹⁶Bi — Unstable · t½ ≈ 9.0 s · Decay: α → ¹⁹²Tl · Type: synthetic · Uses: research.
¹⁹⁷Bi — Unstable · t½ ≈ 10.0 s · Decay: α → ¹⁹³Tl · Type: synthetic · Uses: research.
¹⁹⁸Bi — Unstable · t½ ≈ 18.0 s · Decay: α → ¹⁹⁴Tl · Type: synthetic · Uses: research.
¹⁹⁹Bi — Unstable · t½ ≈ 28.0 s · Decay: α → ¹⁹⁵Tl · Type: synthetic · Uses: research.
²⁰⁰Bi — Unstable · t½ ≈ 37.0 s · Decay: α → ¹⁹⁶Tl · Type: synthetic · Uses: research.
²⁰¹Bi — Unstable · t½ ≈ 1.7 min · Decay: α → ¹⁹⁷Tl · Type: synthetic · Uses: research.
²⁰²Bi — Unstable · t½ ≈ 2.0 min · Decay: α → ¹⁹⁸Tl · Type: synthetic · Uses: research.
²⁰³Bi — Unstable · t½ ≈ 11.8 min · Decay: α → ¹⁹⁹Tl · Type: synthetic · Uses: research.
²⁰⁴Bi — Unstable · t½ ≈ 11.2 min · Decay: α → ²⁰⁰Tl · Type: synthetic · Uses: research.
²⁰⁵Bi — Unstable · t½ ≈ 15.3 d · Decay: EC → ²⁰⁵Pb · Type: tracer · Uses: nuclear physics.
²⁰⁶Bi — Unstable · t½ ≈ 6.2 d · Decay: β⁻ → ²⁰⁶Po · Type: tracer · Uses: nuclear physics.
²⁰⁷Bi — Unstable · t½ ≈ 31.6 y · Decay: β⁻ → ²⁰⁷Po · Type: activation product · Uses: environmental tracer.
²⁰⁸Bi — Unstable · t½ ≈ 3.68×10⁵ y · Decay: β⁻ → ²⁰⁸Po · Type: long-lived radionuclide · Uses: astrophysics.
²⁰⁹Bi — Unstable · t½ ≈ 1.9×10¹⁹ y · Decay: α → ²⁰⁵Tl · Type: quasi-stable (was long considered stable) · Uses: standard reference isotope.
²¹⁰Bi — Unstable · t½ ≈ 5.0 d · Decay: β⁻ → ²¹⁰Po · Type: natural (Uranium series) · Uses: tracer, radiation studies.
²¹¹Bi — Unstable · t½ ≈ 2.1 min · Decay: α → ²⁰⁷Tl · Type: natural (Uranium series) · Uses: tracer.
²¹²Bi — Unstable · t½ ≈ 60.6 min · Decay: α/β⁻ → ²⁰⁸Tl/²¹²Po · Type: natural (Thorium series) · Uses: tracer.
²¹³Bi — Unstable · t½ ≈ 45.6 min · Decay: α/β⁻ → ²⁰⁹Tl/²¹³Po · Type: natural (Actinium series) · Uses: tracer.
²¹⁴Bi — Unstable · t½ ≈ 19.9 min · Decay: β⁻ → ²¹⁴Po · Type: natural (Uranium series) · Uses: tracer.
²¹⁵Bi — Unstable · t½ ≈ 7.6 min · Decay: β⁻ → ²¹⁵Po · Type: synthetic · Uses: research.
²¹⁶Bi — Unstable · t½ ≈ 2.3 min · Decay: β⁻ → ²¹⁶Po · Type: synthetic · Uses: research.
²¹⁷Bi — Unstable · t½ ≈ 1.5 min · Decay: β⁻ → ²¹⁷Po · Type: synthetic · Uses: research.
²¹⁸Bi — Unstable · t½ ≈ 30.0 s · Decay: β⁻ → ²¹⁸Po · Type: synthetic · Uses: research.
²¹⁹Bi — Unstable · t½ ≈ 15.0 s · Decay: β⁻ → ²¹⁹Po · Type: synthetic · Uses: research.
²²⁰Bi — Unstable · t½ ≈ 10.0 s · Decay: β⁻ → ²²⁰Po · Type: synthetic · Uses: research.
²²¹Bi — Unstable · t½ ≈ 6.0 s · Decay: β⁻ → ²²¹Po · Type: synthetic · Uses: research.
²²²Bi — Unstable · t½ ≈ 4.0 s · Decay: β⁻ → ²²²Po · Type: synthetic · Uses: research.
²²³Bi — Unstable · t½ ≈ 2.0 s · Decay: β⁻ → ²²³Po · Type: synthetic · Uses: research.
²²⁴Bi — Unstable · t½ ≈ 0.8 s · Decay: β⁻ → ²²⁴Po · Type: synthetic · Uses: research.
Bismuth — isotope count: 41 total · Stable: none (²⁰⁹Bi is quasi-stable with extremely long half-life) · Unstable: 41.
(Data: IAEA LiveChart, NUBASE2020, ENSDF; notable applications: ²⁰⁹Bi as standard reference isotope, ²¹²Bi/²¹³Bi in medical research, Bi isotopes in astrophysics and tracer studies.)
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