Polarization [%] Beam polarimetry (Compton/Møller) Helicity flip scheme (delayed/quartet/duo) Energy range [GeV] Energy measurement (Arc/EP) Current range (µA] Spot size (h × v) [σ] [µm] Raster size (square/round) (h × v/ø) [mm] Energy spread [σ] Energy lock |
none required No N/A approx. 1.16 GeV Yes up to 80 100-200 2 × 2 10 × 10-4 yes |
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Targets (specify thickness) Photon radiator LH2 (4/15/20 cm) LD2 (4/15/20 cm) Helium-3/4 (4/10/15/20 cm) Target ladder angle (w.r.t. beam) Solid targets (specify each) |
N/A LH2 @ 4 cm or 6cm from pi0 experiment N/A N/A Normal 12C optics, Ta foil, 12C foil, BeO |
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Spectrometers (specify required detectors) | |||
HRS-L Angle range [°] Momentum range [GeV/c] VDC1 VDC2 S0 S1 S2 Gas Cherenkov (long/short) A1 A2 FPP Preshower/Shower |
12.5 - 22.0 0.75 - 0.82 (negative) Yes Yes Yes Possible (T4 trigger) Yes (F1TDC) N/A N/A No No Yes |
HRS-R Angle range [°] Momentum range [GeV/c] VDC1 VDC2 S0 S1 S2 Gas Cherenkov (long/short) A1 A2 FPP Preshower/Shower |
13.2 - 50.0 0.53 - 0.68 (positive) Yes Yes Yes Possible (T4 trigger) Yes (F1TDC) Yes (short) N/A Yes No Yes |
Trigger/DAQ Coincidence/single Define trigger |
Coincidence S0 & S2M and S0 & S2M |
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Also need two out of three triggers. For electron arm, gas Cherenkov will work. For hadron arm, can use aerogel Cherenkov. | |||
Other Instrumentation none |