PANDA TAG Tracking

Minutes for 10th of November:

present: O. Hartmann, S. Neubert, J. Ritman, M. Steinke, J. Symrski, F. Hügging. excused: K.-T. Brinkmann, P. Gianotti, B. Ketzer, L. Schmitt.

Top 1: Forward Tracker: Requirements, Design Choices and Simulation questions

Jerzy gives a nice presentation summarizing the requirements and simulation efforts needed for the Forward Tracker. Here only brief key points are mentioned together with the items discussed afterwards. The full picture can be seen in Jerzy's presentation either as ppt-file or as pdf-file.

• Jerzy mentioned the uncertainties concerning the maximum count rates per wire which he expects in the order of 10^5 per s. Matthias claims that to this topic new simulation results from Alex are now available (see IronplateVRVS_061106.pdf for more details) roughly confirming Jerzy's estimation.
• Of particular importance are the ageing requirements and the momentum resolution which should be in the same range as for the Central Tracker, i.e. 1%.
• The position resolution per detection layer is expected to be ~200µm for the Target Spectrometer (TS) and ~300µm for Forward Spectrometer(FS) resp. This is roughly a factor 2 or 3 lower than the intrinsic resolution of the wire chamber taking into account calibration issues and wire position uncertainties.
• For the FS the lower angular acceptance will be limited by the elastic scattering processes which highly increases the the rate load on the wire. It is now expected by 1.5° but this must be confirmed with full background simulations, e.g. for the benchmark process pbar p -> lambdabar lambda.
• Main part of the optimization work of the design deals with an optimization of the momentum resolution. Therefore different positions and groupings of the detection layers either in the TS and the FS will tested to get the optimal relative momentum resolution in dependency from the momentum and the TŽtheta angle.
• For the FS also the angular acceptance has to be optimized , especially because of slow pions coming from D* decays.
• Piotr H. has agreed to take care about the simulation work to be done; results can be expected by the next PANDA meeting in December. Matthias mentioned that Jan Z. has already implemented some tracking into the Fast Reconstruction for the STT which can be also useful for the FT.
• Concerning the design choices Jerzy mentioned the most critical criteria which are the high rate capability, the ageing effects and the reliability of the system.
• Matthias raises the important point of the event mixing which is also for FT a problem (for details again see IronplateVRVS_061106.pdf). Unfortunately the MDC or Straws only give a time resolution of about 100ns and cannot gain so much by decreasing the drift lengths. This must be considered and one can probably taking advantages of the efforts done by the TPC. Furthermore also the MVD can provide a slightly better time resolution even for single forward MVD hits of the order of 50ns.
• Some kind of B-field mapping either for the iron plate or the chicane option is available and will be provided to Piotr.

Top 2: Next meetings

The next meeting will deal MVD and most likely will take place on Tuesday the 21th of November, 16:00. But this has to be confirmed. Afterwards meeting(s) concerning the Central Tracker (STT and/or TPC) will be scheduled before the next PANDA meeting.

Top 3: Any other business

Nothing to report.

-- FabianHuegging - 10 Nov 2006