T474 phone conference 
Thursday 18 may 2006, 16:30 GMTPhone number : 0871 271 2900 (inside UK) +44 870 050 6800 (outside UK)Meeting code : 255404 
discussion points 

minutes 
Minutes of the 18 May 2006 T474 Phone conference   Yury will distribute a stripped down of the analysis code based upon the BaBar framework, together with scripts to extract the cavity parameters. We will install this code at UCL and set up the processing of the data on our cluster.  Yury produced a somewhat of a 'chronological' list of analysis tasks: 1. Need to define some quick algorithm to get the BPM resolutions *Bino* will put this as a routine in libRooEsa which is available from the UCL CVS repository and send around. 2. We need to study in detail the extrapolation for saturated pulses and define some standard way of handling these events We volunteered *Mark* to do this. > Steward raised the question whether the FFT for a saturated and unsaturated waveform are the same. This should be checked ! > One important point here brought up by Yury is the t0 determination, he will study this. 3. Optimization of the DDC algorithm (frequencies, gamma) either by common sense tuning of the parameters or finding somehow a mathematical best optimization. *Fillimon* and *Bino* will look into this. 4. Go over the calibrations for all the runs, IQ 5. Look at the resolution and stability 6. Overall orbit fitting, see remark mike below. 7. Added here a little additional list from stewart on systematic studies :  correlate temperature (BPM, ambient) with resolution, stability  study effect of bunch charge, bunch length  internal vs. external clocking  beam optics (455 vs. 458)  Mike brought up the point that we should first handle the last runs taken as these have the best data in, so it might be a good idea to process the runs in the opposite order.  Yury gave a brief explanation of how the BaBar framework is structured. The code is organized in different more or less independent modules (classes) which add different levels of processing to a central event object.  Mike stated that we should start studying different ways of establishing the orbit as T480 can also benifit from this as well as the stability studies. A weighted (1/resolution^2) fit would be the way to go, prefereably using a parabola to account for the earth's magnetic field. We also need to be aware here that Q38 was never completely off, albeit at very low field, so this might introduce a correction to the trajectory. Bino is working on a least squares fitting algorithm that will be able to extract the misalignments.  Fillimon will provide a runlist with calibration runs, with internal and external clock and send it around.  The online logbooks are copied over from SLAC and can be found under https://www.hep.ucl.ac.uk/elog/ILC+eSpec+@+ESA/ Next to these we have setup a T474 analysis logbook as well under : https://www.hep.ucl.ac.uk/elog/Linear+Collider/ Need to setup a wiki page either at Berkeley or UCL.  We will try to organize a phone conference with SLAC during our visit to Dubna. Details will be sent around.  The next T474 phone conference will be held 2 weeks from now on June 1st 16:30 UK time. We will look for an alternative phonenumber. Details will be send around some days before the meeting. 