News on PANDA ToF from ITEP (new mechanic design for DRPC based system)

1. ITEP News on PANDA ToF from ITEP(new mechanic design for DRPC based system) Alexander Akindinov ITEP(Moscow) Russia-Panda meeting — April 26-28, 2010, ITEP(Moscow)

2. Requirements for PANDA • Small radius ~ 50 cm • Minimal radiation length • “Holes” for pellet target • About 100 % coverage Strip design modules with plastic covers and chamber fixation

3. Our old design As we found out from current design of PANDA barrel 4 mm gap between detectors foreseen (space for service and installation structure + cabling and ect.) 7 degree shift 422 + 4 mm= 426 mm • About 100% coverage • Minimal material budget • “Holes” for pellet target – to be done • 56 identical modules in total 500 - 4 mm = 496 mm

4. Some open questions • We have some ideas how to fix strips, but we need to know common support structure for DIRC and TOF • From B. Lewandowski : “We have these 16 rectangular formsplanned for quartz boxes. … It would be excellent, if you could start a design for theTOF in a way similar to the one for the DIRC quartz boxes, because thematerial of these two systems have to be as close as possible togetherto improve the situation for the EMC “. – As you can see TOF is as close to DIRC as possible, we’ll redesign our current drawings to 16 sectors, but we need some time. • From C. Schwarz: “Is it possible to have a single layer and optimized housings coveringapprox. 90% of the geometrical acceptance?” – We can do this, but we have to check if PCB (1.2x1.2 m2) with parameters we need can be produced. In this case design will be very similar to IHEP-Dubna project. Also we need to redesign chamber support and chamber placement (4 rows). We also can design 16 sector segmentation with two layers (strips in each sector fixed together mechanically) feedback from the other subdetectors &subsystems very important!!!!!

5. We got some information after March meeting(1) Information from BwECAL. Many thank to David Rodríguez Piñeiro  for providing very useful information. Frame for services BwECAL and tracker coupling We’ll keep this in mind

6. We got some information after March meeting(2) Information from DIRC. Many thank to Carsten for providing very fast reply. 422 + 4 mm= 426 mm 500 - 4 mm = 496 mm

7. Inputs for new design • Inner radius – 426 mm (as for old one) • Outer radius – 483 mm (one row?) • 16 sectors as for the DIRC (!) • We try in any case to have geometrical coverage as high as possible We think this is a very good idea, but how we can do this for one layer only? We can fit 4 strips in one gas volume to form 22.50 sector and save space for at least 2 covers!

8. We had a very few time due to LHC start again… but we have already new design (not so detailed like old one but with very similar strips)

9. Old and new dimension

10. Segmentation for supermodule 3 strips sector is not fit very well with DIRC sector The best solution as for us. Two type for supermodule should be produced

11. Electronics and services FOPI supermodule Readout connectors PCB FEE H.V.

12. Summary New system design for barrel TOF was done. We are now fit as well into space between tracker and DIRC. We rearranged strips to have 16 sectors.(4 strips in one module preferred) The aim is to have one side services and readout, but we need to produce PCB ASAP to confirm this!!! New ROOT model will be done soon (fortunately not so many things to change) We will update our EDMS documents: https://edms.cern.ch/document/1063856/1 and https://edms.cern.ch/document/1064701/1 Many thanks again for feedback from the other subdetectors!!!!!

13. BACKUP

14. Strip design 100 mm 100 mm 1500 mm Zoom view for place of PCBs merging region