September 9, 2011
summary what was been done
| Run # | Beam | Dump magnet | Collimator | Radiator 10 um Al | Target | Comments |
|---|---|---|---|---|---|---|
| 2339 | Up 2 mm | In | Open | Up 2 mm | No | R(upstream) = 2648/35092 = 0.075 e+/pulse, R(downstream) = 3191/35092 = 0.091 e+/pulse |
| 2341 | Up 2 mm | In | Open | Out | No | R(upstream) = 1088/35494 = 0.031 e+/pulse, R(downstream) = 1328/35494 = 0.037 e+/pulse. About 59% of photons are coming from the radiator. Bad |
| 2342 | Down 2 mm | In | Open | Out | No | R(upstream) = 1586/36678 = 0.043 e+/pulse, R(downstream) = 1888/36678 = 0.051 e+/pulse. |
| 2343 | Down 2 mm | In | Open | Down 2 mm | No | R(upstream) = 2232/35488 = 0.063 e+/pulse.
About 32% of photons are coming from the radiator. Bad |
| 2344 | Centered | In | Open | Centered | No | R(upstream) = 2683/35095 = 0.076 e+/pulse. |
| 2345 | Centered | In | Open | Out | No | R(upstream) = 1039/35094 = 0.029 e+/pulse.
About 62% of photons are coming from the radiator. Bad |
| 2346 | Centered | In | Open | Out | No | R(upstream) = 1286/35885 = 0.036 e+/pulse.
Improved shielding around dump. |
| Based on the previous results the beam is total crap, so beam tuned up. | ||||||
| 2349 | Centered | In | Open | Out | No | R(upstream) = 404/35489 = 0.011 e+/pulse. |
| 2350 | Centered | In | Open | Out | No | R(upstream) = 428/35093 = 0.012 e+/pulse.
Additional shielding around the vacuum window of the beam pipe. |
| 2351 | Centered | In | Open | Centered | No | R(upstream) = 1314/35094 = 0.037 e+/pulse.
About 68% of photons are coming from the radiator. Still bad. Additional shielding around the vacuum window of the beam pipe is removed. |
| 2352 | Up 2 mm | In | Open | Up 2 mm | D2O bottle | Production run. |
| 2353 | Up 2 mm | In | Open | Out | D2O bottle | background check threshold @A22 lowered to -100 mV |
| 2354 | Up 2 mm | In | Open | Up 2 mm | DU plate | Production run. R(upstream) = 4228/188008 = 0.022 e+/pulse R(upstream) = 5169/188008 = 0.027 e+/pulse |
| 2355 | Up 2 mm | In | Open | Out | DU plate | background check threshold @A20 lowered to -100 mV |
Beam Realignment
Screen shot using Phosphorous screen
Electron beam on glass
12pm upstream view screen
12pm downstream view screen
