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-groupsize: 5 is a good number. Increasing this number will make better references, but they may also make them less accurate, as you would be averaging a larger number of profiles. If you decide to increase this number by a factor, then I would also increase n by the same factor, so in the end the total number of reference is the same. (see also thoughts from Tim Maxwell below).

-roexpand and roiwaistthres: Call the method 'ProcessedXTCAVImage'. If the image does not look clipped, the parameters are fine.

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• For single bunch: As low as possible while still removing the noise (i.e.) not getting noise current profiles.
• For double bunch: As low as possible while separating the two bunches. Call the 'ProcessedXTCAVImage' method again, and look at the size of axis 0: this will be the number of bunches detected. You can probably write a program to automatize the determination of this parameter, until you get lets say a 95% of two bunch detection.

Thoughts from Tim Maxwell on Number of Groups

Two cases:

• normal sase (not many beam-related fluctuations): take sqrt of number shots and use that many groups (beat down background noise with lots of averaging)
• slotted foil (many beam-related of fluctuations): restrict it to 5-10 images per group, make as many groups as possible using typically 30 seconds to a minute of data at 60Hz.

120Hz Operation Issues

(Thought from Tim Maxwell on 2/2/2015, discouraging this mode of operation)

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