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Thin screen scintillation model

 

tex2html_wrap_inline3922   Inhomogeneities of refractive index in a thin screen, mid way between source and observer
tex2html_wrap_inline3922   Essentially a Young's double slit experiment, but with multiple slits
tex2html_wrap_inline3922   An interference pattern forms
tex2html_wrap_inline3922   Earth and pulsar motion cause different parts of the interference pattern to be sampled
tex2html_wrap_inline3922   Results in random flux variations
tex2html_wrap_inline3922   Interference pattern is frequency dependent

   figure310
Figure 11: The thin screen model. From Lyne & Graham-Smith 1990 [23]

tex2html_wrap_inline3922   Wavelength scale of amplitude variations is tex2html_wrap_inline4332

equation233

tex2html_wrap_inline3922   In practice the screen has thickness D and the frequency bandwidth of amplitude variations is

equation237

   figure328
Figure 12: Amplitude variations of PSR B0329+54 as a function of time as observed using MERLIN



Jon Bell
Thu Dec 19 15:15:11 GMT 1996