ECal Items

1
ECal Items
Ray Frey, UO

• ECal Optimization Issues OLD Results
• Longitudinal depth
• Longitudinal sampling
• (ECal Radius)

2
Old SD 30 Layers x (5/7) X0 21 X0. 50 GeV
electrons
Total Absorbed Energy
Total Energy in Si
?E / E 0.16 / ?E
3
Old vs New Sampling Configurations
50 GeV electrons
SD 30 x 5/7 X0 (21.4)
SD vB 20 x 5/7 X0 10 x 10/7 X0 (28.6 X0)

• better containment
• poorer sampling

4
Alternative Sampling (contd.)
500 GeV electrons
SD 30 x 5/7 X0
SD vB 20 x 5/7 X0 10 x 10/7 X0
5
Alternative Sampling (contd.) resolution
500 GeV electrons Energy in Si
SD 30 x 5/7 X0
SD vB 20 x 5/7 X0 10 x 10/7 X0
6
Reminder shower width

• Old SD 5x5 mm2 pixels with (1) 0.4mm or (2)
  2.5mm readout gaps.
• 10 GeV photons look at layer 10

7
ECal Optimizations

• It seems that ?30 X0 is a reasonable choice for
  EM shower containment
• Increasing sampling at larger depth is probably
  advisable
• Need to study affect on resolution for several
  possibilities
• How coarse can it be? Where can coarse sampling
  begin?
• Where does a hadron pattern recognition issue
  kick in ?