[Olympus] Summary of collaboration meeting 8-11 July, 2013

[Douglas Kenneth Hasell]

Dear Colleagues,

	Over the past 4 days I think we have enjoyed a very useful collaboration m=
eeting.  The slides are of course available on the Wiki:

https://olympus-docu.hiskp.uni-bonn.de/dokuwiki/doku.php?id=3Dcollaboration=
-meeting-jul2013

but I would like to summarise some of the main points here for those who we=
re not able to attend:

1. The next collaboration meeting will be 17-18 October at DESY.  This is a=
 week before the PRC meeting 24-25 October at DESY.

2. There was some discussion about also having a radiative corrections work=
shop at DESY around the time of the collaboration meeting.  There is also a=
 radiative corrections workshop at Orsay 7-8 October which we are investiga=
ting combining.

3. I encourage every group or individual to document their work and keep th=
is up to date.  These can be internal notes or on the Wiki but they should =
be clearly written so so one can come along in a year and reproduce the wor=
k if necessary just following your documentations.

4. The analysis of the magnetic field mapping is well along and should be f=
inished in a few weeks.  Residuals in the wire chamber volume are small.  T=
he 12 degree and Moller region is not as good and Axel is investigating a s=
eparate fit to that area.

5. The optical survey analysis by Jan is also well advanced and during the =
workshop on Tuesday a number of outstanding issues were resolved.  Still a =
few things to finish.  Colton will put everything into the GDML.

6. During numerous discussions we converged on a coordinate system with ori=
gin at the  centre of the target cell and Z axis along the scattering chamb=
er axis.

7. The Monte Carlo has been incorporated in the cooker framework.  Everyone=
 should use this.  Monday afternoon Brian gave some instruction of using th=
e cooker followed by Lauren with instructions on using the new MC.

8. People are urged to implement digitization for each detector.  The TOF i=
s mostly done.  WC work has started.  MWPC needs to be ported to repository=
.  A GEM digitization has started.

9. Generators should be added to the MC. Plan is to have common radiative c=
orrections with JLAB and Novosibirsk. Nicola has a generator based on Maxim=
on and Tjon which should be added to the repository and tested.

10. Most runs are usable with the simple quality flag.  A more detailed exa=
mination has started but then need to decide on skipping Moller blocks or s=
imulating.

11. The TOF analysis and status is quite good. Denis found the problem with=
 overflow in the ADC that caused funny behavior.  Timing offsets and ADC ga=
ins seem to be consistent and more or less complete between the various ana=
lyses.  Attenuation lengths are consistent but disappointing. Digitization =
is mostly finished with some small details to fix. Falling edge of ADC sign=
al for proton is sharper in data than in MC which is not understood. Worksh=
op discussed things still to do like a global analysis once tracking in pla=
ce, correct the bar offsets from cosmic, redo top/bottom offsets.  Question=
 about speed of light or TDC calibration unclear.  Leading edge discriminat=
ors in last bars need special handling for walk.  There is still an discrep=
ancy between the pedestals determined in the pedestal data at the start of =
each run and that collected during the run.  Further detailed work probably=
 needs the tracking.

12. A GDML problem for the TOF was discovered and Colton is fixing that.  C=
olton will also produce a list of material in the MC for all detectors.

13. Algorithm for PID from the TOF can be started.

14. Philipp reported on the reprocessing of ZEBRA raw files underway at Bon=
n.  Should finish this week then can be checked, fixed, and new ROOT files =
sent to DESY and MIT.

15. Upcoming talks:

Nicola - Gomel, Belarus
Roberto - JLAB
Jan - Boppard
Michael - APS
Ozgur - APS
Brian - APS
Rebecca - APS
Michael - EINN

16. Wire Chamber work that needs to be done is to revisit T0 calibration af=
ter removing 100 ns bumps.  Create data base of TDC widths for scaling time=
 to distance.  Redo pattern matching with new magnetic field.  =


17. Work on track reconstruction will start once magnetic field and optical=
 survey, WC calibration, new raw ROOT files, etc. in place.  Will use an it=
erative approach to determine time to distance from fit tracks.

18. Still some discussion on blinding the data.  Purpose is to stop people =
from tuning fits or cuts to get a specific result.  Also prevents accidenta=
l release of a result.

19. Nicola updated his analysis of the February data.  Analysis is fine but=
 reconstruction of negative field data poor and leads to bad ratios.

20. Moller/Bhabha analysis progressing.  MC is running but needs detector d=
igitization.  Losses larger than previously reported and now ratio not as g=
ood.  Needs to be investigated further.  Need to investigate beyond tree le=
vel. Also compare coincidence and master-slave results.

21. Ozgur showed very nice results from the GEM telescopes.  Digitization n=
eeds to be implemented.  Efficiencies are too high and need to be investiga=
ted. Very good resolutions around 60 microns are found.  J=FCrgen will writ=
e a SiPM plug-in.  Lorentz angle effects should be included in analysis and=
 MC.

22. MWPC digitization ready but should be put in repository.  Alexander wil=
l update the geometry with Jan. Rate of events in MWPC less than SC expecta=
tions.

23. Once TOF simulation complete need to write a trigger simulation.

	If I have forgotten or misrepresented anything please let me know.

                                                    Cheers,
                                                            Douglas

26-415 M.I.T.                                 Tel: +1 (617) 258-7199
77 Massachusetts Avenue                       Fax: +1 (617) 258-5440
Cambridge, MA 02139, USA                      E-mail: hasell at mit.edu       =
    =




-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/pkcs7-signature
Size: 1586 bytes
Desc: not available
Url : http://mailman.mit.edu/pipermail/olympus/attachments/20130712/6b51b95=
e/attachment.bin