1. *Institute of Space Science
TB2016 – pedestal analysis
Veta Ghenescu*
*Institute of Space Science
11/17/2016

2. Experimental set-up LumiCal LumiCal e- beam 2cm Tracker target
1st telescope arm
magnet
2nd telescope arm
L 2
L 1 R1 R2
Channels:
4 sectors:
Tracker planes consist of LumiCal sensors without absorber layers;
Lumical calorimeter consists of 6 Si sensors with one absorber layer placed in front of each active sensor layer;
Questions:
- Sectors R1 and R2 were connected to the Master chip
- Sectors L1 and L2 were connected to the Slave chip
LumiCal 1 . 62 63
127
126 . 65 64 W
Tungsten absorbers
Silicon sensors
2/29/2016

3. Without charge divider
Data
#Run
Hit position ~ pad no
Energy beam
Observation
Without charge divider
588
X = 87.5, y = ~ Pad 18
5 GeV
No target, no mag field
606
X = 47.3, y = ~ Pad 49
636
Target =1.5mm Magnetic field, I = 90A
704
X = 47.3, y = ~ Pad 49
Target = 1.5mm
Magnetic field, I = 90A
With charge divider*
741
X = 94.1, y = ~ Pad 20
No target , no mag field
767
X = 94.1, y = ~ Pad 20
Target = 1.5 mm
789
Target = 2.5 mm
*The charge divider wasn’t installed on all APVs. The trackers were without charge divider all the time

4. Pedestal - #tracker 1

5. Pedestal - #tracker 2

6. Pedestal - #layer 1

7. Pedestal - #layer 2

8. Pedestal - #layer 3

9. Pedestal - #layer 4

10. Pedestal - #layer 5

11. Pedestal - #layer 6 - TAB

12. Conclusions
the
The pedestal was analysis for all APVs and for different experimental conditions as follow:
w/ and w/o charger divider
w and w/o magnetic field
w/ and w/o target
For trackers the pedestal is almost the same;
For LumiCal layers w/o charge divider the pedestal decrease channel by channel,
For LumiCal layers w/ charge divider the pedestal is almost constant for channels placed on the L1 and R2 sectors;