Explain the difference between a fluorescence emission spectrum and a fluorescence excitation spectrum. which more closely resembles an absorption spectrum?

In a fluorescence emission spectrum, the excitation wavelength is held constant and the emission intensity is measured as a function of the emission wavelength. In an excitation spectrum, the emission is measured at one wavelength while the excitation wavelengths are scanned. The excitation spectrum closely resembles an absorption spectrum since the emission intensity is usually proportional to the absorbance of the molecule.

For me a person with a phd and who knows what there talking about.i know the chances of a radiation leak is low but if it does the area within a 96.3 mile radius would be unusable because of contamination