Bohr magneton

https://dx.doi.org/10.1351/goldbook.B00692
Electromagnetic fundamental physical constant:
μ B = e ℏ 2 m e = 9.274 0154 31 × 10 −24 J T −1
where e is the elementary charge, ℏ the Planck constant divided by 2 π and m e the electron rest mass.
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