12 10 2012 HRRL DetectorTests
12/12/12
Worked on evaluating the background after the installation of 8" thick Pb wall in accelerator room and installing a FC, Scintillator, and Phosphorous screen at the end of the 90 degree line.
12/13/12
Worked on establishing a small spot size on the Phosphorous target and then documenting the beam properties.
12/14/12
Worked on establishing a small spot size on the Phosphorous target and then documenting the beam properties.
12/19/12
When Target T1 goes in and Accelerator side lights up( as viewed by scintillator Kelly) and Illyusha (when next to the beam exit window) also lights.
There is no Pb around T1.
Lets directionally shield Illyusha (when positioned next to the hallway) to determine how much lead to add around T1.
ADC3 = NaI Left
ADC7 = NaI Right
TDC 29 = NaI right
TDC 31 = NaI left
Area | Conditions |
800 \pm 130 pVs | No shielding T1 in |
1600 \pm 200 pVs | 1 Pb brick (2") shielding T1 in Add Pb and signal goes up? Just noise! |
Move Illyusha so it is right next to experimental side flag, no shielding. |
Take data using 3 MeV electrons on the T2 target.
The Scintillator known as Kelly is has an output of about 1 Volt.
Run # | Configuration |
4611 | T1 and T2 are in, Veto discrimnator, ADC overflows , TDC31-TDC29 looks OK, 25 Hz counting rate |
4612 | T1 and T2 are in, Veto discrimnator, cut the beam current in half, rate is 0.06 Hz |
4613 | T1 and T2 are in, Veto discrimnator, cut the beam current in half, rate is 4 Hz, lowered threshold from 20 to 7 mV |
4614 | T1 in T2 out, Veto discrimnator, cut the beam current in half, rate is 0.03 Hz |
Take data using 3 MeV Positrons on the T2 target.
The Scintillator known as Kelly is has an output of about 1 Volt.
ADC9 = NaI right
Run # | Configuration |
4621 | T1 and T2 are in, Veto discrimnator, threshold is 5 mV, Kelly at 3.5 Volt ,rate is 0.2 Hz |
12/20/2012
RF noise measurement
Run # | Configuration | ADC3 | ADC9 |
4625 | Na-22 Source run with RF no beam current |
RF adds 50 channels of noise to NaI signal and moves Source peak forward.
RF was for 3 MeV electrons, perhaps RF for higher energy electrons will add the remaining 30 channels of noise on the NaI detectors.
Positron attempt
Run # | Configuration | ADC3 | ADC9 |
4632 | Transporting 3 MeV positrons, Looks like beam right (ADC9) has 511s beam left (ADC3) swamped with photons | 200 px | 200 px |
Need to shield beam left more.
Scintillator and Quartz cabling
Changed the scintillator detector known as "Jenni" so its HV is controlled remotely through connector SHV59A7 and its signal is on connector 223A7.
Kelly is the scintillator on the accelerator side.
The quartz detector is on connector SHV59A8 and the signal on 223A8.