Difference: 20151104_MSciSpectrocopyMeeting ( vs. 1)

Revision 104 Nov 2015 - AshleaKemp

Line: 1 to 1
META TOPICPARENT name="StewartBoogertSpectroscopy2015"
Meeting Notes

Present: Ashlea Kemp, Joe Bayley, Elena Cukanovaite, David Hadden, Professor Boogert, Professor Cowan

  • Make sure to include some mathematics onto twiki i.e. the functions that were plotted to graphs, explain each parameter
  • Make sure to include numerical values onto twiki (values for mean positions, etc)
  • Check $\chi^{2}$ value - should not be that small!
 \begin{equation} \chi2 = \sum \frac{(x_i - \mu)^2}{\sigma^2} \end{equation} <br />

  • Want to find wavelength as a function of pixel position along x axis and micrometer setting, i.e. $\lambda(x,m)$
  • Fit one peak at a time in each frame, and find 3 parameters for each spectral lines: mean position $\mu_{i}$, its corresponding wavelength $\lambda_{i}$ and micrometer setting $m_{i}$. Once complete for whole spectrum, try and fit function $\lambda(x,m)$ for data. Find $\chi^{2}$ for functional fit to help determine the best functional fit i.e. linear, quadratic etc.
  • Origin of increasing background from left - right: at one side of CCD, there is some electronics generating heat and noise, hence there is some unavoidable rising background due the way camera is built. Can take Bias frame with 0 exposure to explore this
  • Normalise values to pixel per second exposure time.
  • Algorithm to search for hot pixels: for 1D, want to look at some derivative change.
 \begin{equation} \frac {P_2-P_1}{\delta x} \end{equation} <br />

-- AshleaKemp - 04 Nov 2015

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