9. PID TAG VRVS Meeting (13.7.2007)

• Introduction, Georg Schepers, Intro-pidtag9_13.07.07.ppt
• Endcap detectors
  • PID - Magnet-Design
    • Global PANDA Design and Influence on the Detectors and PID, Lars Schmitt, LS12-070705_techboard.pdf
  • Kaon Pion separation with the ToP design, Markus Ehrenfried Ehrenfried_Pion_Kaon_separation.pdf
  • comparability of results
• compact status reports from the detectors
• EMC
  • new results from the Electron-Pion separation, Bertram Kopf EpEmStatus0707.pdf
• Decisions

• Introduction, Georg Schepers, Intro-pidtag9_13.07.07.ppt
  • As an introduction to the meeting Georg Schepers (as the chair) remarked that the task of the PID TAG of PANDA stays concentrated on the Requirements from Pysics and that it has to give a statement about the optimal detector system to accomplish these. Technical decisions are done elsewhere. Nevertheless, the new considerations of the technical coordinator should be known by the TAG members as well.
• Endcap detectors
  • PID - Magnet-Design
    • Global PANDA Design and Influence on the Detectors and PID, Lars Schmitt, LS12-070705_techboard.pdf
      • Lars Schmitt presented the considerations about the PID Detectors regarding the considerations of a more compact magnet design. The shorter magnet would deminish the magnet forces (from 100 to 7 tonns), the amount of iron and for example the number of EMC moduls. As a consequence the Endcap Cherenkov must be closer to the target zone with a smaller (Disc-)radius. This migt be very difficult if not impossible to realize for the Focussing Disc DIRC.
        • There were questions whether the GEM detectors which will replace the Drift chambers provide enough track imformation for high resolution what Lars approved strongly.
        • The PID TAG is asked for evaluation of the necessity of the high separation power of the Focussing Disc DIRC which seem to outperform the two other possible detector at this position, the ToP-DIRC and the Proximity Rich with GEM foil readout.
        • Bertram Kopf proposed to ask the people who analyze the physics channels for the Physics Book to provide phase space plots (momentum vs theta angle as well as transversal momentum vs parallel momentum) as an important input for the PID TAG to decide for the needed resolutions.
  • Kaon Pion separation with the ToP design, Markus Ehrenfried Ehrenfried_Pion_Kaon_separation.pdf
    • In the presentation of Markus Ehrenfried calculation with the ToP-DIRC setup with the new reduced size positioned in the smaller magnet were shown and the results compared with the outcome of the olt ToP-DIRC- and magnet-design. Both results were "within error bars" the same (in the smaller setup the ratio between the area read out and the complete disc area is bigger).
  • comparability of results
    • We heard again, that, as we knew from the Erlangen Workshop, the spezifications and definitions are not quite clear. Markus showed his value for the separation power he defind as Separation Power = Delta /sqrt(sigma_k**2+sigma_pi**2) with delta as the distance between the mean values of the gaussian distributed particle entries.
    • Markus was also asking that the calculations for the Endcap detectors have to be done with the same definitions to obtain a clear result that allows to really compare the performances.
• compact status reports from the detectors
  • Quirin Weitzel told that the install of the TPC in the PANDAroot framework progressed well.
  • Carsten Schwarz reported the efforts of Annalisa Cecchi who implementes an parametrized photon propagation for the Barrel DIRC in the PANDAroot. In addition a ToF-detector will be installed in the PANDAroot by Alicia Sanchez who needs it for the use of her secondary target counter in the investigation of Hyper nuclei.
• EMC
  • new results from the Electron-Pion separation, Bertram Kopf EpEmStatus0707.pdf
    • Bertram showed new results of his pbar p to electron positron simulation for the EMC. With help of the Neural Network an Background(mainly comming from pi0) a needed Background substraction to a level of 10**-8 ist not so far. One point he noted was that in the backward region of the Target Spectrometer (100 to 180 degree) the electron identification of the EMC becomes worse but the identification with the Barrel DIRC becomes excellent, which is an important reason to have the Barrel DIRC. Another importent remark Bertram had to the position of the Cherenkov counters which cause a preshower to the EMC. The Distance of EMC and DIRC is 11cm for the Barrel DIRC and 5cm for the Endcap. For the particles which pass the DIRCs with a big angles the distance grows up to more than 30cm and the resolution of the EMC deteriorates strongly.
• Decisions
  • It was renewed that we need comparable results for the performance concerning separation power of the Endcap detectors.
  • Bertram will asked input from the analysts of the physics channels
  • A next meeting should be performed in two to three weeks from now (to be announced).