Which term refers to energy per unit mass absorbed by an object?

The term that refers to energy per unit mass absorbed by an object is known as the Gray (Gy). This measurement specifically quantifies the amount of radiation energy deposited in a material, where one Gray is defined as the absorption of one joule of radiation energy by one kilogram of matter.

The Gray is a crucial unit in the context of radiation dosage in medical physics and radiation safety. It serves to assess the potential biological effects of radiation exposure, as the amount of energy absorbed by tissue can influence the degree of damage incurred.

While the term "Gyt" is essentially a representation of the Gray, it is more commonly noted as "Gy," so understanding the context of the unit being discussed is vital. Hence, the correct answer aligns with the specific terminology referencing the unit of energy absorption relevant in medical and safety contexts.

Other terms listed, such as LET (Linear Energy Transfer) and Sv (Sievert), pertain to different aspects of radiation measurement. LET refers to the energy transferred per unit distance traveled by ionizing radiation, while the Sievert measures the biological effect of radiation, not just the energy absorbed. These distinctions underscore the correct selection of the Gray based on its direct relation to energy absorption per unit mass.