Need help manipulating absorption spectroscopy data please

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SUMMARY

The discussion centers on manipulating laser absorption spectroscopy data for rubidium isotopes, specifically Rb87 and Rb85, using MATLAB. The users are facing challenges in accurately scaling their oscilloscope plots, which are affected by the fringe pattern from a Michelson Interferometer. They seek a method to stretch the absorption spectrum plot to its correct size, utilizing the numerical data extracted from the oscilloscope. The conversation highlights the need for a formula or technique in MATLAB to achieve this adjustment.

PREREQUISITES
  • Understanding of laser spectroscopy principles, particularly for rubidium isotopes.
  • Familiarity with MATLAB for data manipulation and plotting.
  • Knowledge of Michelson Interferometer operation and its impact on spectral data.
  • Basic skills in data extraction from oscilloscope measurements.
NEXT STEPS
  • Research MATLAB functions for data interpolation and scaling.
  • Explore techniques for correcting spectral data based on interferometric fringe patterns.
  • Learn about data visualization best practices in MATLAB for accurate representation.
  • Investigate methods for analyzing and processing laser absorption spectra.
USEFUL FOR

Researchers and students in the field of spectroscopy, physicists working with laser systems, and data analysts focused on optical measurements will benefit from this discussion.

Calcifur
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Hi guys,
So my project partner and I are struggling to solve a problem with our laser spectroscopy data for rubidium isotopes and I thought it may be a good idea to see if you could help us.

If you take a look at the attached image you will see that the blue line shows our doppler free laser absorption bands for Rb87 f=2 state and Rb85 f=3 state, the yellow line is the fringe pattern of our corresponding Michelson Interferometer which we have been using to monitor the change in frequency of our laser.

Now, the problem that I'm hoping you may be able to help us with is that we want to produce the same plot but streched out to the regular size it should be. In other words if you take a look again at the Michelson line, you will see that the fringes compress together at certain parts and stretch away at others (caused by the scanning of the diffraction grating used to change the laser frequency), and these compressions and rarefactions occur on the absoption line too at the same parts. Consequently,the oscilloscope is not actually showing the absortion spectrum to the correct scale, if you get my meaning.

Given that we have extracted the numerical data for the oscilloscope plots for both lines, do you know if there's a way I can fix the plot in Matlab, with a formula or something?

I know my explanation is vague, Is just its hard for me to describe the problem in words but feel free to message any questions.

Many thanks in advance!
 

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No takers huh? If anyone is having trouble understanding my problem please let me know or ask any questions. Many Thanks
 
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