Recoil Proton Detector

Figure 1: The Recoil Proton Detector and Target

Eventually, a 30-cm target will be used, but initially a 1-in Be target will be surrounded by an array of counters to detect the recoil proton. The recoil proton detector is shown in the drawing of Figure 1.

The beam comes in from the left. In this initial detector, a 2-fold coincidence ring subtends 40^o to 60^o at the target. The correlation between the recoil proton momentum and angle (with respect to the beam) is shown in Figure 2 for various photo-produced particles.

Figure 2

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