PANDA TAG Tracking

Minutes for 13th of June:

Top 1: Tracking Requirements

Benchmark Channels:

The choice of the tracking benchmark channels have been re-discussed and adjusted to accomplish our needs. In particular it has been decided that

• pbar p -> D D -> K pi pi will be replaced by pbar p -> D* D* -> K pi pi , note that K can either be K+,K- or K0 to ensure the best tracking and vertexing performance for all kind of kaons. Furthermore the decay channels D* -> slow pions must be considered to check the possibilities for low momentum particle tracking.
• pbar A -> J/Psi -> mu mu X will be replaced by pbar A -> J/Psi -> l l X to consider the tracking of electrons as well.

It is clear that for a meanigful assessment a lot of statistic is needed. Therefore the technical problems of the MC generators for signal and background processes should not be underestimated and must be addressed soon. In addition the question whether the generators for pbar-nucleus reaction are adequate for our needs was mentioned but not answered. Both topics are slightley beyond the scope of this TAG because our task is to give recommendations which questions has to answered by the different tracking sub-detetcors to reach an optimal PANDA tracking system. But of course the feasibility of the proposed simulation studies must assured and therefore a re-assessment of the benchmark channels might be neccessary.

The problem of a significant physics channel to evaluate the impact of the iron plate in the Forward Spectrometer was shortly discussed. Although no adequate channel could be identified it was stressed that this question is very important and the discussion should be again brought up to a wider audience.

Discussion on 'How to proceed?':

We agreed to seperate the work concerning the 'tracking requirements' for each of the three sub-components Micro-vertex-Detector (MVD), Central Tracker (CT) and Forward Detector (FT). For each sub-system a responsible will be nominated which should serve as 'interface' between the TAG and the simulation groups. This person will be the contact person for the simulation group which will provide the necessary expected detector parameters (i.e. expected resolutions, material distributions etc.) and he/she will follow closley the results coming from the simulations to focus the work in the right directions. Finally he/she should compile in collaboration with the simulation and TAG group a list of 'questions' which has to be answered by the simulation effort or sub-system R&D. Eventually the end of this process will lead to a derivation of the tracking requirements for the PANDA tracking sub-systems. In this sense it has to be stressed that it is not the task of our TAG to define the final 'tracking requirements', rather we have to fix a frame of physics cases which challenges the PANDA tracking system mostly. In order to be usable in the future, e.g. for the upcoming design choices, this frame has to be as detailed as possible, i.e. all aspects of the 'required detector performance' has to be considered like space point, track, momentum, vertex and time resolutions together with efficiency, purity and material aspects.

We agreed that the sub-system responsibles are:

• MVD: Fabian Huegging
• CT: will be defined later
• FT: Piotr Hawranek

Finally I encourage everybody to put information about the expected detector performance of the different detector options into the TAG Wiki page. This will be very helpful for the future discussions and work of our TAG.

Top 2: Design Choices

It was decided to change slightley the format of the important design choice with respect to the three central tracking sub-systems. Basically we will have two major design choices, in particular:

• CT: TPC or STT1 - Frascati design, skewed or STT2 - Jülich design, skwed or STT3 - Jülich design, double sided readout
• FT: MDC1 - Dubna design or MDC2 - Cracow design or Straws

The draft of the 'tracking document' and the Wiki page will be changed accordingly.

Criteria Definition

Up to now a collection of criterias for the design choices are given in our document, although they are rather general. Next step is to re-iterate them with respect to specific design choice and order them regarding their importance. Unfortunately the time for a further discussion was too short so it was postponed to the next meeting.

Timeframe discussion

Here also the no progress was achieved since the no time was left.

Any other business

Next meeting via VRVS will be beginning of August, to be announced.

-- FabianHuegging - 04 Jul 2006