MiniPrototype SinglesCosmicRuns 2008
Goal
Use singles Cosmic events to measure rate differences between Metalica and Plastica
Apparatus
- Plastica and Metalica are stacked on top of each other. High Voltage and ionization gas are connected in parallel.
- A discriminator is connector to the amplified output (an on board preamp and the VPI Post amp) of sense wire 4.
- The discriminator output is connected to a VME scaler.
Proposed Tests
- Measure the singles rate as a function of DC high voltage
- Measure the singles rate as a function of Discriminator Threshold
30-04-2008
The DC high voltage is on. The DC outputs of Plastika and Metalica from sense wire 3 are connected to the Model 777 Octal Variable Gain Amplifier.
HV settings | ||
Wire | Volts | |
Sense | 1700 | |
Field | -800 | |
Guard | 800 |
Scope picture below shows the Noise level on the DC measured in infinite persist time mode.
Scope pictures representing the cosmic signals from Plastika and Metalica(Amplifier is connected)
- Plastika
- Metalica
OUTPUTS FROM DISCRIMINATOR
- Discriminator Threshold=450MV
Rate -vs- Discriminator Threshold
- Gas is ArCo2 . 75/25 mixture
HV settings | ||
Wire | Volts | |
Sense | 1700 | |
Field | -850 | |
Guard | 850 |
Threshold (mV) | Metalica (Events/hr) | plastika (Events/hr) | Coincidence |
300 | 701 | 627 | |
300 | 560 | 570 | |
350 | 511 | 454 | |
350 | 382 | 334 |