• elog entries: https://him-elog-01.him.uni-mainz.de/Beamtime+January+2018/page1

Please check the nitrogen pressure twice a day! Approximately 50 bar per day are used.

The bottles are placed in the detector lab in the A1 ground floor.

Beam test 31/1 – 5/2/2018:

1. start with smallest current (1 nA)
2. if event rate too high: install picoamperemeter

For each setting:

• measure rates
• take spectrum (look at gamma and e spectra)

Steps:

1. set up coincidence between EMC and scintillator
2. increase beam current up to 100 nA in various steps → find appropriate current value
3. change thresholds
4. move prototype with the xy table
5. set up coincidence with spectrometer A

1. recognise one or more energy peaks
   • elastic on C (nucleus)
   • elastic on H
   • inelastic on H in coinc. with spec. A
2. adjust HV
3. change angle or spec. A settings for changing the peak energy

1. vary beam current → find appropriate value
2. threshold scan at the smallest angle
3. vary scattering angles

1. use second scintillator at different angles for electrons
2. set up triple coincidence
3. change spec. A polarity to measure electrons
4. set up coincidence with spec. A
5. measure gamma spectrum changing angle and spectrometer settings (measure end-point of the gamma spectrum)
6. try different targets C,CH2,Ta

1. change beam energy (until Friday noon!)
2. increase beam current to appropriate value
3. repeat measurements for energy calibration
4. repeat measurements for total rate
5. repeat measurements for pi0 event identification