# Difference between revisions of "Doppler Broadening"

## Photon emmision along direction of fission fragment velocit

= amount of energy the gamma ray was shifted by

where is the Doppler-shifted -ray energy which was measured

=- for an excited fragment in det-1
=- for an excited fragment in det-2

is the polar emission angle of excited fragment and the fragment velocity

=0.04634

Our Calculations

For example for energy E=2617 keV and the fragment velocity v= cm/s(speed of light c=3x cm/s, =0.033, =0.999455352)
We obtained the following results for different angles between the direction of the fission fragment propagation and the direction of the gamma emission

(i) =

=2532.02 keV

(ii) =

=2618.43 keV

(iii) =

=2704.83 keV

FWHM(for energy 2617 keV)=2.5 keV(experimental data)

Energy difference -=172.8 keV. This result shows us that we do not have Doppler Shift.

# Cf-252 Fission

## Photon Spectra from Cf-252

References: http://prola.aps.org/pdf/PR/v104/i3/p699_1

Smith, A. B.; Fields, P. R.; Friedman A. M., Physical Review, vol. 104, Issue 3, pp. 699 - 702