Lab Notebook reference Vol. 2 pp. 86 - 88.
Notes: Data collected at -2V applied detector bias, T = 7K, 14.1µm filter, pinhole.
Purpose:
1. Quantify spot size as function of echelle turns
2. Verify echelle best focus
3. Calculate echelle resolving power at best focus
4. Investigate grating parameters and determine grating input angle using spot locations
5. Calculate km/s per pixel at best focus for this grating angle
6) Compare km/s spot size to theory for this angle and grating parameters
1) In this data set the echelle was set to the C2H2 Q-branch. A sample image (at nominal best focus of 14T) is shown here:
Odd/even variation is apparent, suggesting broadening is not an issue in this data. We can use ImageJ to make a profile plot along the line:
An unfortunate fact is that we did not save a rinsed cell at each focus position in this set, just at the initial (14T position). Using Matt's clickfit idl procedure in 2D mode is going to be problematic. To get a idea of focus we can use ImageJ to grab profile plots and then fit them with gaussian profiles in Kaleidagraph. Let's try to select the same line in each frame, and do an x- and a y- gaussfit.
File : turns : FWHM-x : FWHM-y
boo5.fits : 14T :
Turns out that it isn't worth pursuing this much further without the rinsed cell data. Will retake (with rinses) in CD9.
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