Hardware R&D Strategy define requirements for detector technology –match with assumptions in simulation –define milestones for next prototype/mini-FoCal full detector important issues (not comprehensive): –two-shower separation HGL yes! – effects of LGL? –energy resolution LGL –integration all 1

Two-Shower Separation HGL: possible with MAPS technology –main issue: current chips not adequate, need new sensors assume further development of ALPIDE will work impact of LGL –not relevant for pion discrimination at low occupancy –smaller pad size might help in high occupancy situation investigate 5x5 mm 2 pads? 2

Energy Resolution in strawman design HGL not used for energy –may help, not a crucial issue now impact of LGL –earlier tests showed sufficient energy resolution to be confirmed –smaller pad size might help in high occupancy situation more channels - larger noise? 3

Integration detector advantage relies strongly on small Moliere radius and high granularity only tests of small scale prototypes –no feasible design yet which is appropriate for real detector services need a lot of room –will dilute Moliere radius –may lead to significant acceptance holes (tower design with gaps) different R&D lines not compatible –need to define standards to use for all 4

Next Step: Design of Realistic Prototype design requirements –minimize room for services longitudinal summing: how? –no (significant) acceptance gaps –tower vs. slats? initiate tests of crucial issues –build mechanical prototype –test cable/PCB design (noise?) appoint “task force” 5