How can I calculate the errors in using Doppler shifts for binary stars?

[stevemclaren]

hey guys,

im doing a report on binary stars, using doppler shifts to get some results for periods etc but bit unsure about how to do the errors?

i realize that the errors arise in the speed of the stars and the dispersion of the photons but how could i calculate this?

cheers for any help
x

 

[malawi_glenn]

Are you familar with the ordninary error-propagation forumula?

 

[stevemclaren]

yeh i know a bit about that, (dx/X)^2 and all that?
how do i calculate the error in dispersion and that tho?
x

 

[malawi_glenn]

http://sosnick.uchicago.edu/propagation_errors.pdf

Look at page 8, and follow that chapter.

Then you write your formula for Doppler shift as a function of frequency and speed of star. What is the definition of dispersion?