Question

What is the nominal value of Dmax for 6MV and 10MV?

please show work.

Answer 1

Dmax is the depth at which maximum dose ( i.e 100 %) of the incident high energy X-ray beams is delivered inside a medium. Beyond that the energy is absorbed in the medium. This term is mainly used in radiotherapy treatment where the medium is human tissue.

Dmax is a parameter that depends on the energy of the primary photon. Ideally it independent of other parameters such as source to skin distance (SSD) and field size.

Dmax values for 6MV and 10MV photons are as follows:

6MV - 1.5 cm

10MV -   2.5 cm