Fitting

  • For numerical way try doubling the x range
  • look at running the fit for more iterations to get correct value
  • wings have some other complicated structure
  • restrict $\gamma$ and $\sigma$ to be positive and put bounds on parameters
  • run the fit to get good guesses to speed up the fitting process
  • Look at the published vega lines and determine whether parameters are similar
  • look at eloide [http://atlas.obs-hp.fr/elodie/] spectra,
    • look at data file
    • convolute with our instrumental response and compare to our fit
  • Plot a vertical dotted line for the real value of $\lambda$
  • Look at how $\sigma$ scales with the central value of the line
  • look at finding physical parameters from the $\sigma$ and $\gamma$

Errors

  • think about what is causing the fluctuation within the lamp
  • Look at using a larger gain, as could be an underestimate
  • could be the noise of the electronics,
    • Look at the errors when the CCD is cooled right down

-- JosephBayley - 29 Jan 2016

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Topic revision: r1 - 29 Jan 2016 - JosephBayley

 
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