MV - not a unit of energy (MeV, however, is)

[Carotenoid]

---

Members do not see this ad.

I am confused, please help!

Why is it that photon beam energy is discussed in terms of mega volts? volt is a unit of potential, not energy... Or does the MV designation refer to the potential through which the electrons that ultimately produce the the photons, are accelerated? e.g. "6 MV photons" are produced when electrons are accelerated through the potential of 6 MV (where electrons themselves acquire 6 MeV of energy).

Thank you!!!

 

[deleted4401]

Come on man... Surgeons still say "sonti-meters" and we say "ob-LIKE". It's all convention. Yes, 6MV photons are actually at an average... But we say it for ease and standardization

 

[hot sauce]

I am confused, please help!

Why is it that photon beam energy is discussed in terms of mega volts? volt is a unit of potential, not energy... Or does the MV designation refer to the potential through which the electrons that ultimately produce the the photons, are accelerated? e.g. "6 MV photons" are produced when electrons are accelerated through the potential of 6 MV (where electrons themselves acquire 6 MeV of energy).

Thank you!!!

You basically understand it. The electrons are accelerated to 6 MeV (there isn't actually a 6 MV field - microwaves are used to accelerate the electrons) prior to colliding with the target. So, a 6MV photon beam is actually a heterogenous beam with a maximum energy of 6 MeV (and an average of ~1.5 MeV if I recall correctly).