Barn b
About the Barn
The barn, exactly 10⁻²⁸ square metres, measures the cross-section of nuclear reactions. American physicists coined the name during wartime work, joking that a uranium nucleus was as big as a barn by nuclear standards. Particle collider luminosity is measured in inverse femtobarns.
Related Units
Hectare
ha1 ha = 10,000 m² (exact)
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Acre
ac4046.8564224 m² (exact)
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Tsubo
坪400/121 m² ≈ 3.306 m²
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Electronvolt
eV1.602176634 × 10⁻¹⁹ J (exact)
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