Difference between revisions of "Beam Test Meeting Mon. May. 07, 2012"
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#* Maximum ADC from downstream ch2 R491/R498 = 3300/4000 = 0.83 | #* Maximum ADC from downstream ch2 R491/R498 = 3300/4000 = 0.83 | ||
#[https://halldweb1.jlab.org/wiki/images/c/c3/Fcal_range_484.ps FADC range from Run 484: Vbr=1.2V] (Andrei) | #[https://halldweb1.jlab.org/wiki/images/c/c3/Fcal_range_484.ps FADC range from Run 484: Vbr=1.2V] (Andrei) | ||
| + | # Bcal data to be taken | ||
| + | #* TDC threshold scan | ||
| + | #* Vover=1.2 V, 4 files 80k each, nominal TDC threshold | ||
| + | #* Vover=0.9 V, 4 files 80k each, nominal TDC threshold | ||
| + | #* Vover=1.2 V, 4 files 80k each, 1/2 TDC threshold | ||
| + | #* Vover=0.9 V, 4 files 80k each, 1/2 TDC threshold | ||
| + | #* Vover=1.2 V, 4 files 80k each, 1/4 TDC threshold | ||
| + | #* Vover=0.9 V, 4 files 80k each, 1/4 TDC threshold | ||
| + | # Considerations in choosing the SiPM operating voltage (Notes by Elton) | ||
| + | #* PDE increases with overbias (favors 1.2 V) | ||
| + | #* Noise increases with overbias (favors 0.9 V) | ||
| + | #* Higher voltage decreases sensitivity to absolute bias voltage setting (favors 1.2 V) | ||
| + | #* Gain increases with overbias, relaxing the electronic gain requirements (favors 1.2 V) | ||
Revision as of 17:17, 7 May 2012
- Preliminary look at pulse heights and times (Elton)
- Media:Run491 histos.pdf Run 491 (Vbr=0.9 V)
- Media:Run498 histos.pdf Run 498 (Vbr=1.2 V)
- What gains do we want to run at?
- Gain Ratio (from Andrei's plot): Vbr=0.9/Vbr=1.2 = 1800/2500 = 0.72
- Maximum ADC from downstream ch2 R491/R498 = 3300/4000 = 0.83
- FADC range from Run 484: Vbr=1.2V (Andrei)
- Bcal data to be taken
- TDC threshold scan
- Vover=1.2 V, 4 files 80k each, nominal TDC threshold
- Vover=0.9 V, 4 files 80k each, nominal TDC threshold
- Vover=1.2 V, 4 files 80k each, 1/2 TDC threshold
- Vover=0.9 V, 4 files 80k each, 1/2 TDC threshold
- Vover=1.2 V, 4 files 80k each, 1/4 TDC threshold
- Vover=0.9 V, 4 files 80k each, 1/4 TDC threshold
- Considerations in choosing the SiPM operating voltage (Notes by Elton)
- PDE increases with overbias (favors 1.2 V)
- Noise increases with overbias (favors 0.9 V)
- Higher voltage decreases sensitivity to absolute bias voltage setting (favors 1.2 V)
- Gain increases with overbias, relaxing the electronic gain requirements (favors 1.2 V)
