There are two domain results: time-domain and frequency-domain.
To get time-domain results, you will need to use time monitor. You can get the spectrum from the time domain monitor which uses Fourier transform. It does not normalize with the source spectrum. Usually it gives you the resonance for a very broad band.
The data is obtained though discrete Fourier transform during the simulation. It is steady-state, CW result without any time-related information. By default it is normalized with the source spectrum. Please refer