What are the air kerma units for measuring dose?

The air kerma units for measuring dose are expressed in Joules per kilogram (J/kg) and Gray (Gy). Air kerma is specifically defined as the kinetic energy released per unit mass of air and is a crucial measurement in radiation dosimetry.

The Gray is a SI unit that directly denotes the amount of absorbed dose in the material, which in this case is air. Specifically, one Gray is defined as the absorption of one joule of radiation energy by one kilogram of matter. This representation highlights the relationship between energy deposition and mass, which is essential for evaluating the effects of ionizing radiation.

While other choices present various units related to radiation, they do not pertain specifically to air kerma. For instance, Gy and Rad both measure dose, but only Gy is the SI unit. The Sievert (Sv) and Roentgen deal more with biological effects and exposure, while the Roentgen (R) and Rem relate to exposure and dose equivalent, respectively, not specifically to air kerma. Therefore, the correct answer reflects the appropriate units relevant to measuring air kerma in radiation physics.