Integration issues - endcap acceptance
Suppose we enlarge the endcaps to cover the entire acceptance of the muon arms,
for event vertices between z=+-10 cm (yellow). On the drawing below, this is done only
for the top-right quadrant. The gray lines indicate the muon arm acceptance,
and the red lines the central arm acceptance (eta=+-0.35).
The endcaps in the figure start at r=2.5cm, and z=23, 28, 33, 38 cm.
The lengths in this projection are approximately 14, 19, 22, 25 cm. From
the lengths we get a chip count:
| endcap:
| 1
| 2
| 3
| 4
| (48 wedges) total
|
| chip count before
| 8
| 11
| 11
| 11
| 1968
|
| after
| 11
| 15
| 17
| 19
| 2976
|
... a 50% increase in chip count
Starting with an inner wedge (trapezoid with x = 5.4 and 16.0 mm and
y=66.0mm), holding
5 readout chips, we extrapolate the area to wedges holding 11, 15,
17 and 19 chips:
|
| ----old----
| ----new----
|
| cone
| chips
| area
| chips
| area
|
| 1
| 8
| 700 cm2
| 11
| 1183 cm2
|
| 2
| 11
| 1150
| 15
| 1768
|
| 3
| 11
| 1150
| 17
| 2290
|
| 4
| 11
| 1150
| 19
| 2832
|
| total
| 1968
| 4160 cm2
| 2976
| 8073 cm2
|
... a doubling of silicon area
The highest point is now 27 cm from the beam axis.
Last update 5 Jan 04 - HvH