SUMMARY OF THE DISCUSSIONS AT THE JAMBOREE ========================================== The jamboree held at DESY on February 13-15 2006 provided an unprecedented opportunity for in-depth presentations and discussions on beam and cosmic-ray tests of TPCs. All the groups from ILC, T2K and even PANDA had a chance to present their methods, ideas and this reflects in the tranparencies available from the TPC jamboree web site: https://ilcsupport.desy.de/cdsagenda/fullAgenda.php?ida=a0591 (easy to link by google TPC jamboree) We try here to complement the transparencies by adding a summary of the questions raised all along the discussions and recommendations for presentations of future results and analysis. Four implementations of the global likelihood fit exist (JTPC in Java by Dean Karlen, FTPC in Fortran 95 by Kirsten Sachs, one in C++ in DESY by M.E. Janssen, one in C++ in Barcelona). They should be compared. General informations to be provided in a talk: - pad pitch and layout - gas used (preferably P5 as a reference) - magnetic field - gain - noise level (for instance r.m.s. in ADC counts) Plots showing the data content, as: - detector acceptance phi distribution theta distribution ? intercept x_0, z_0 - charge deposition of a row (a hit) (to show the amount of saturation and noise) QUALITY STANDARDS A lot of good will was shown by the participants to define quality criteria of an analysis to allow meaningful comparisons. Track selection, hit selection To avoid biasing the results by selecting very specific tracks, the selection cuts should be reduced to a minimum and justified. However fiducial cuts to ensure a good data quality are recommended if needed. Effect of cutting or keeping saturated hits has to be assessed. An estimate of the selection efficiency has to be given. Resolution analysis We should show residual distributions (for instance at a given z) to allow estimating the tails and the shape. To define the resolution, we should use - RMS of residual distibution, after cutting outliers * not less than 5*RMS cut (iterative process) - Avoid bias from the track extrapolation error. To this end, taking the geometric mean of fits with and without the test row is the preferred method. Also simple methods like the triplet method or the extrapolation between adjacent rows are correct, provided the right statistical factor is used. - For cosmics, a phi cut at +-0.1 rad is recommended, for sake of comparison without cutting too much statistics. However, depending on trigger and aspect ratio, one can have to change this. The best, if statistics allows, is to show phi dependence of the resolution. The same is true for theta, here a cut at 0.2 rad is indicated. Useful information that should be provided: - fraction of 1-pad, 2-pad, 3-pad hits (especially if one of these categories is rejected) - fit of the resolution with a sigma0 and a Neff for large enough drift distance that a parabolic dependence can be fitted: sigma = sqrt(sigma0**2+(CD**2/Neff)*z) We should also provide checks - bias plots (residuals vs position in the pad) - probability of the chi^2 (if one uses such a fit) or pull distribution IMPLEMENTATION ISSUES The question was raised of keeping a universal LCIO format, to facilitate exchanges, while being able to generate separately the ionisation in the gas (time consumming) and the digitization by the amplification device, that we want to modify easily (technology, pad geometry). This problem should be brought to EUDET/NA2. FUTURE COMMUNICATION ideas - web site - use the following mailing list (to be completed) - next telephone meeting in 2-3 months - a jamboree every 6 months (next in September? in Aachen?) Matthias Enno Janssen and Paul Colas Appendix - List of Registered Participants Paul Colas Paul.Colas@cea.fr CEA SAclay Ron Settles settles@mppmu.mpg.de Max-Planck-Institute for Physics, Munich & Desy, Hamburg Federico Sanchez fsanchez@ifae.es Universitat Autonoma de Barcelona Katsumasa Ikematsu Katsumasa.Ikematsu@desy.de DESY Quirin Weitzel qweitzel@e18.physik.tu-muenchen.de TU Muenchen, E18 Adrian Vogel adrian.vogel@desy.de DESY Vincent Lepeltier lepeltie@lal.in2p3.fr LAL Orsay Ties Behnke ties.behnke@desy.de DESY Peter Wienemann peter.wienemann@physik.uni-freiburg.de Freiburg univ. Joachim Mnich Joachim.Mnich@desy.de DESY Jan Timmermans jan.timmermans@cern.ch NIKHEF Thomas Zerguerras zerguer@ipno.in2p3.fr IPN Orsay/RDD Volker Eckardt voe@mppmu.mpg.de MPI Munich (retired) Dan Burke dburke@cea.fr CEA Saclay Max Chefdeville chefdevi@nikhef.nl Astrid Muennich muennich@physik.rwth-aachen.de RWTH Aachen Martin Killenberg killenberg@physik.rwth-aachen.de RWTH Aachen Kirsten Sachs kirsten.sachs@desy.de Carleton University Marco Zito zito@in2p3.fr CEA Saclay Peter Kluit s01@nikhef.nl NIKHEF Michael Hauschild Michael.Hauschild@cern.ch CERN Dean Karlen karlen@uvic.ca Michael Weber michael.weber@physik.rwth-aachen.de RWTH Aachen Hirotoshi Kuroiwa kuroiwah@vbl.hiroshima-u.ac.jp Hiroshima University Anthony Sarrat Anthony.Sarrat@cea.fr Bernhard Ledermann Ledermann@ickp.fzk.de FZ Karlsruhe