Hi,

To illustrate technical articles about EM radiations, I' m searching for
thermal images of antennas during transmission ?

Wow...

That's no longer very common.

Some people have run smaller antennas on thermal paper to map the
currents/voltages.

But a true thermal digital image of an antenna in situ is very difficult,
because of convection currents.

A more common mode is to attach thermal sensors at various points on the
antenna and map the temp as a function of time.

Is that what you had in mind?

73,
Chip N1IR