Accelerating apparatus for a radiation device

An accelerating apparatus, comprising:

• a plurality of acceleration cavity units including a plurality of acceleration cavities;
• and
• a plurality of coupling cavity units each of which includes a coupling cavity, two adjacent acceleration cavities being electromagnetically coupled via the coupling cavity, wherein
• the plurality of acceleration cavity units has a plurality of holes each of which is configured to form a coupling channel between an acceleration cavity and a coupling cavity;
• at least one of the plurality of holes is located at a location of an inner surface of the acceleration cavity where electromagnetic field strength is maximum.

An accelerating apparatus, comprising:

• a plurality of acceleration cavity units including a plurality of acceleration cavities;
• and
• a plurality of coupling cavity units each of which includes a coupling cavity, two adjacent acceleration cavities being electromagnetically coupled via the coupling cavity, wherein
• the plurality of acceleration cavity units has a plurality of holes each of which is configured to form a coupling channel between an acceleration cavity and a coupling cavity;
• and
• a long axis of the each hole is perpendicular to a moving direction of a radiation beam in the acceleration cavity.