Hi.

I'm looking for information on time bandwidth product in terms of FWHM
and RMS Width for various functions. Specifically, for these
functions:

E(t)= exp(- abs(t/T)) two sided exponential.
E(t) = exp (- t/T) one sided exponential.
E(t) = Sech^2(t/T) hyperbolic secant square
E(t) = rect(t/T) rectangular pulse.

I actually want the width values in terms of the intensity of these
functions I(t) = E(t)E(t)*. , not the amplitude.
I have actually computed all the width values but just want to compare
it to the correct ones. If there's a table, book, or website that has
any info, please let me know.

For the one sided exponential and the rectangular pulse, I believe the
RMS width doesn't exist, or according to my calculation, the integral
for either <t^2> or <w^2> doesn't converge, but I think there's a value
for the rest.