Gray Gy
About the Gray
The gray measures absorbed dose of ionising radiation, one joule of energy deposited per kilogram of matter. It is named after the British physicist Louis Harold Gray. It replaced the rad, which is exactly 0.01 Gy.
Related Units
Becquerel
Bq1 Bq = 1 s⁻¹ (one decay per second)
The becquerel is an activity of one radioactive decay per second, named after Henri Becquerel, who discovered...
Sievert
Sv1 Sv = 1 J/kg = 1 m²·s⁻²
The sievert measures the biological effect of radiation, weighting the absorbed dose by radiation type and tissue...
Curie
Ci3.7 × 10¹⁰ Bq (exact)
The curie, exactly 3.7 × 10¹⁰ decays per second, was based on the activity of one gram of radium-226. It is named after...
Roentgen
R2.58 × 10⁻⁴ C/kg (exact)
The roentgen measures exposure to X-rays and gamma rays by the ionisation they produce in air, exactly 2.58 × 10⁻⁴...