# FT of a pulse

Dear All,
Suppose we have a electromagnetic/x-ray pulse with fixed energy with finite line width. I want to know the schematic of a plot how it looks in time- and frequency-domain?
I think I understand in time domain: there will a straight vertical line on plotting intensity vs time in x-axis.
Regards, raj.

BvU
Homework Helper
Dear All,
Suppose we have a electromagnetic/x-ray pulse with fixed energy with finite line width. I want to know the schematic of a plot how it looks in time- and frequency-domain?
the line width you mention IS the width of the spectrum in the frequency domain.
I think I understand in time domain: there will a straight vertical line on plotting intensity vs time in x-axis.
Regards, raj.
In that case you have a delta function; the frequency spectrum for that is a constant for all frequencies.

You have to compromise for realistic cases; the easiest is a pulse with a gaussian shape: the frequency spectrum is also a gaussian. The sharper the pulse, the wider the frequency spectrum.
Check out some fourier transforms

Hello,
So if there is a vertical line in the time domain then it will be a horizontal line in the frequency domain. If yes, please give me the physical meaning!
Thanks, raj.

BvU
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