1. Analysis Drift velocity of the SDD Detector
Martin A. Subieta
INFN Torino
Introduction
SDD detector
Drift velocity
Description of ITS Layer 3 & Layer 4
Status of the anodes for all modules
Analysis
Mean Drift velocity and Time bin for all Modules
Mean Drift velocity on the Ladders
Mean Drift velocity and Time bin in function of the runs (fluctuations in the time = 1 minute of data analyzed per run)
Conclusions
Palau, Sardegna September 30th

2. SDD Detector Analysis Drift Velocity of the SDD Detector Side 0

3. Drift Velocity
The particle cross the detector and produces the electron’s cloud
Electron’s cloud goes until the anodes
The drift velocity is the mean velocity of the electrons Z X
Analysis Drift Velocity of the SDD Detector

4. ITS Layer 3 & Layer 4 Total Modules 260 Layer 3 Layer 4 N° of Ladders14 22
N° SDDs per
Ladder 6 8
Total Modules
Analysis Drift Velocity of the SDD Detector

5. Injectors Lines 2 1 3 Status pad injector 5 6 7 Pad 1 & 3 Pad 2 & 3
Analysis Drift Velocity of the SDD Detector

6. Status Injector Pad Statistics
Total number of pads are 17160
45 % of the pads have status 7
18 % have status 6
1.2 % have status 5
16.8 % have status 1-4
19 % have status 0
Pads 1 & 33 not working for almost all modules
Analysis Drift Velocity of the SDD Detector

7. Statistics of Modules Status 7
Side 1 pad 7 have more modules with status 7
Side 0 pad 27 have more modules with status 7
For both sides we have more of the 50% of the total number of modules with status 7
Analysis Drift Velocity of the SDD Detector

8. Analysis Mean Drift Velocity (Vdrift)
Analysis of the Vdrift of the pad 7 for one side for the run (one minute data taking analyzed)
Vdrift distribution for all modules
Time bin (Time bin centroid for the 2nd line injector) distribution for all modules
Vdrift distribution on the ladders
Analysis of the Vdrift for the modules 302 and 372 for 7 runs ( 1 every hour )
Vdrift in function for the runs of August 14th
taken each hour
Time bin of the pad 7 in function of the same runs
Runs
Data 14/08/2008
51954
51959
51971
51981
51986
51999
52005
Analysis Drift Velocity of the SDD Detector

9. Mean drift velocity for all modules
Most modules have
Close to 0,08% of error, except for two.
the minimum mean velocity is close to 6.3 (μm/ns) and the maximum close to 6.8 (μm/ns)
Layer 3
Layer 4
Module 273
Module 483
Analysis Drift Velocity of the SDD Detector

10. Time bin centroid for all modules
We take the central injector line for the analysis
Only modules with anodes with status 7 are plotted
Layer 3
Layer 4
Analysis Drift Velocity of the SDD Detector

11. Mean drift velocity for all modules
The picture shows the fluctuations in the modules with status 5,6,7
Most modules have less than 1 per thousand of error
Layer 3
Layer 4
Analysis Drift Velocity of the SDD Detector

12. Time bin centroid for all modules
We take the central injector line for the analysis
Only modules with anodes 5,6,7 are plotted
Layer 3
Layer 4
Analysis Drift Velocity of the SDD Detector

13. Mean drift velocity on the ladders
Drift velocity depends on temperature
Top layer 3 ≈ 25 °C
Bottom layer 3 ≈ 23 °C
Top layer 4 ≈ 22 °C
Bottom layer 4 ≈ 20 °C
Analysis Drift Velocity of the SDD Detector

14. Mean drift velocity vs runs
Stability of the Vdrift on the time =1 min of data analyzed
fluctuations of the Vdrift around of the mean on the all runs
We have a stability close to 1 per thousand for each run, which remains for 7 runs analyzed
Analysis Drift Velocity of the SDD Detector

15. Time bin in function of the runs
Stability of the Time bin on the time is less than 1 per thousand
This stability remains for all runs analyzed
Analysis Drift Velocity of the SDD Detector

16. Conclusions
The 63% of the pads for all 520 semi-modules have status 6,7.
For the modules with anodes that have status 7 the fluctuations of the drift velocity in 60 events collected in 1 minute , have less than 1 per thousand of error.
Drift velocity observed on the ladders indicate a higher temperature on layer 3 than on layer 4. And a higher temperature on the top ladders than on the bottom ones
4. We have a difference close to 5 °C between layer 3 and layer 4
5. Analysis on Vdrift and the Time bin for six hours (every hour with 1 minute of data analyzed ), shows a stability of the order of 1 per thousand
Analysis Drift Velocity of the SDD Detector