Dysprosium-163

Main isotopes of dysprosium

iso NA half-life DM DE (MeV) DP 154Dy syn 3.0×106 y α 2.947 150Gd 156Dy 0.056% is stable with 90 neutrons 158Dy 0.095% is stable with 92 neutrons 160Dy 2.329% is stable with 94 neutrons 161Dy 18.889% is stable with 95 neutrons 162Dy 25.475% is stable with 96 neutrons 163Dy 24.896% is stable with 97 neutrons 164Dy 28.260% is stable with 98 neutrons
Standard atomic weight (Ar)	162.500(1)

Naturally occurring dysprosium (Dy) is composed of 7 stable isotopes, ¹⁵⁶Dy, ¹⁵⁸Dy, ¹⁶⁰Dy, ¹⁶¹Dy, ¹⁶²Dy, ¹⁶³Dy and ¹⁶⁴Dy, with ¹⁶⁴Dy being the most abundant (28.18% natural abundance). Twenty-nine radioisotopes have been characterized, with the most stable being ¹⁵⁴Dy with a half-life of 3.0 million years, ¹⁵⁹Dy with a half-life of 144.4 days, and ¹⁶⁶Dy with a half-life of 81.6 hours. All of the remaining radioactive isotopes have half-lives that are less than 10 hours, and the majority of these have half-lives that are less than 30 seconds. This element also has 12 meta states, with the most stable being ^165mDy (t_1/2 1.257 minutes), ^147mDy (t_1/2 55.7 seconds) and ^145mDy (t_1/2 13.6 seconds).

The primary decay mode before the most abundant stable isotope, ¹⁶⁴Dy, is electron capture, and the primary mode after is beta decay. The primary decay products before ¹⁶⁴Dy are terbium isotopes, and the primary products after are holmium isotopes.

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