Hall A Target Configuration
David Meekins
The following table gives a list of target positions and
materials. Note that the
Target |
Entrance Window (mm) ± 0.005 |
Exit Window (mm) ± 0.005 |
Loop 1 4 cm |
0.127 |
0.149 |
Loop 1 15 cm |
0.114 (Pb 0.279) |
0.174 |
Loop 2 4 cm |
0.127 |
0.113 |
Loop 2 15 cm |
0.118 |
0.040 |
Loop 3 4 cm |
0.112 |
0.140 |
Loop3 15 cm |
0.114 |
0.120 |
The optics target consists of 7 carbon foils cut from the same sheet. The foils are 99.5% chemically pure carbon. Each foil is 0.042 ± 0.001 g/cm2. Foils are separated by 4cm.
The dummy targets are made of Al 6061-T6. All foils are 0.259 ± 0.001 g/ cm2.
The following table gives the target foil position, thicknesses and chemical purities.
Target Position |
Purity |
Thickness g/cm2 |
BeO |
99% |
0.149 ± 0.001 |
C |
99.95% |
0.0838 ± 0.0005 |
Ta |
99.5% |
0.0202 ± 0.0001 |
Slanted C |
99.95% |
0.111 ± 0.001 |
Slanted Fe |
99.5% |
0.119± 0.001 |
The angle of the slanted target is roughly 30 degrees. The actual number can be found from the survey results.