Decades: 470s BC 460s BC 450s BC 440s BC 430s BC - 420s BC - 410s BC 400s BC 390s BC 380s BC 370s BC
Years: 427 BC 426 BC 425 BC 424 BC 423 BC - 422 BC - 421 BC 420 BC 419 BC 418 BC 417 BC
... from Scintillation counter
A scintillometer measures ionizing radiation. The sensor is a crystal that fluoresces when ionizing radiation ...
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