[esa-t474] analysis plan

[Bino Maiheu]

Dear all,

I was thinking it might be beneficial to have a more or less detailed 
analysis plan that would lead up to the next ESA publication. Please
feel free to edit. I've put in some remarks on what should go in the
paper ( type of plots etc... ) as well, in order to direct the analysis
in a certain way. There is for sure a lot more to be learned from the
data, but I guess we will want to make some choices to get a paper out
fast-ish. 


1. goals for the analysis
   * demonstrate the upgrades to the BPM system : calibration tone
   * energy measurement : method, resolution, systematics, simulation


2. BPM positions
   * check internal clock issue : get the frequencies, need to d
     determine t0Offset by fit
     -> so adjusted calibrations are needed

   * helmholtz calibrations : regress against BPMs 31/32 to take out 
     beam jitter and clean up the steps

   * incorporate the toroid information for absolute charge into the 
     calibration scheme
     -> charge information from here instead of the reference cavity... 
     -> can just use raw toroid values, don't need toroid calibration 
        for it
     

3. Calibration tone date
   * find way to correct the BPM data with the calibration tone :

     correct the cavity amplitude before calibration probably, and then 
     use the corrected amplitude in the rest. Level should be set at 
     calibration time and corrections applied afterwards, so we need an 
     additional calibration constant which sets the gain level at the 
     time of calibration... 

     As calibration tone data is sparse, we need to have a structure in 
     memory with calibration tone data which gets updated everytime new 
     calib tone data is available...
     
   * use calib tone phase as well, or just amplitude ??

   * we need position data corrected with calibration tone and without, 
     have to compare the stability over long timescale for both : hope 
     to show that drifts are taken care of by the system
 
   * need plot of calib tone data: amplitude, frequency, phase over 
     long time period compared to temperature, plot it vs temperature & 
     determine correlation


4. Spectrometer

   * routines for energy calculation 
     http://www.hep.ucl.ac.uk/~bino/spectrometer/doc/ 
   * determine energy resolution
   * determine stability of energy resolution, investigate systematic 
     effects
   * comparison with energy BPM readings -> so need them well 
     calibrated as well


I'm starting with item 2 on the list. 

As libbpm will be a well defined contribution to the "BPM world", I feel
it is important to do this analysis while shaving off it's rough edges,
so the BPM routine library is at least left in a good state after our
money runs out or we move on to do different things. So I'll try as much
as I can to do this, but will try to get some ESA results in a
reasonable timescale as well. Probably that will mean using the library
+ esaProcess as it was used for mark's analysis. 

bino


	
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