1. comparison NIKHEF/EUDET card and Siemens/Lake Shore Hall probe F.Bergsma CERN 7/2/2008 Results of last meeting 12/9/2007 Recalibration of cards used in EUDET mapping at DESY NIKHEF card with Lakeshore HGT2100 EUDET card with Siemens KSY44 More tests on NIKHEF card with KSY44 Conclusions

2. 0.37 T 1.14 T 1.4 T   +10 G |B| -5 G T +10 G |B| -5 G T 1 2 NIKHEF after one year NIKHEF Sensor 9 x θ, 16 x φ, step=22.5 o

3.   0.37 T 1.14 T 1.4 T 3 4 +10 G |B| -5 G T +10 G |B| -5 G T NIKHEF after one year NIKHEF Sensor 9 x θ, 16 x φ, step=22.5 o

4.   0.37 T 1.14 T 1.4 T +10 G |B| -5 G T +10 G |B| -5 G T 1 2 EUDET Temp from DS60 Immediat after cal. EUDET Sensor new prototype 9 x θ, 16 x φ, step=22.5 o

5.   0.37 T 1.14 T 1.4 T +10 G |B| -5 G T +10 G |B| -5 G T 1 2 EUDET Temp from DS60 After 6 days EUDET Sensor new prototype 9 x θ, 16 x φ, step=22.5 o

6.   0.37 T 1.14 T 1.4 T +10 G |B| -5 G T +10 G |B| -5 G T 1 2 EUDET Temp from DS60 After 0.24 year EUDET Sensor new prototype 9 x θ, 16 x φ, step=22.5 o

7.   0.37 T 1.14 T 1.4 T +10 G |B| -5 G T +10 G |B| -5 G T 3 4 EUDET Temp from DS60 Immediat after cal. EUDET Sensor new prototype 9 x θ, 16 x φ, step=22.5 o

8.   0.37 T 1.14 T 1.4 T +10 G |B| -5 G T +10 G |B| -5 G T 3 4 EUDET Temp from DS60 After 6 days EUDET Sensor new prototype 9 x θ, 16 x φ, step=22.5 o

9.   0.37 T 1.14 T 1.4 T +10 G |B| -5 G T +10 G |B| -5 G T 3 4 EUDET Temp from DS60 After 0.24 years EUDET Sensor new prototype 9 x θ, 16 x φ, step=22.5 o

10. 0.37 T 1.14 T 1.4 T 12 cards tested, look similar 0 days 6 months recal 6 months +40 days diff 6 months +40 days total Measurements at 22 0 C Calibration done at 20, 24 0 C +15 G -5 G   +15 G -5 G Eudet cards used at DESY card 5 -5 G + 15 G -5 G +15 G -5 G 9 x θ, 16 x φ, step=22.5 o

11.   0.37 T 1.14 T 1.4 T 0 days 6 months recal 6 months +40 days diff 6 months +40 days total 12 cards tested, look similar Eudet cards used at DESY card 6 Measurements at 22 0 C Calibration done at 20, 24 0 C 9 x θ, 16 x φ, step=22.5 o

12.   0.37 T 1.14 T 1.4 T 0 days 6 months recal 6 months +40 days diff 6 months +40 days total 12 cards tested, look similar Eudet cards used at DESY card 7 Measurements at 22 0 C Calibration done at 20, 24 0 C 9 x θ, 16 x φ, step=22.5 o

13. 2 x NIKHEF CARD with 3 X Lakeshore HGT2100

14.   0.37 T 1.14 T 1.4 T NIKHEF card with HGT2100 card 2 After 47 days total 5 After 7days After 0 days After 47 days recal at 40 days +20 G -5 G +20 G -5 G +20 G -5 G +60 G ! 9 x θ, 16 x φ, step=22.5 o

15.   0.37 T 1.14 T 1.4 T NIKHEF card with HGT2100 card 3 After 7days After 0 days After 47 days recal at 40 days +20 G -5 G +20 G -5 G +20 G -5 G +60 G ! After 47 days total 9 x θ, 16 x φ, step=22.5 o

16. 1 x EUDET card with 3 X Siemens KSY44

17.   0.37 T 1.14 T 1.4 T +5 G -5 G Eudet card with KSY44 After 0 days After 21 days After 34 days After 41 days After 48 days 9 x θ, 16 x φ, step=22.5 o

18. Do we have an effect due to excessive heating up during soldering? On the NIKHEF HGT2100 cards we have soldered on a bare smd, no heat sinking, many tries How does the KSY44 behave after soldering?

19.   0.37 T 1.14 T 1.4 T +5 G -5 G 28 days 40 days 47 days 54 days 0 days 2 G NIKHEF card KSY44 normal operation card 1 Measurements at 22 0 C Calibration done at 20, 24 0 C 9 x θ, 16 x φ, step=22.5 o

20. 0.37 T 1.14 T 1.4 T +5 G -5 G 28 days 40 days 47 days 54 days 0 days 2 G Simulation of two times soldering = 2 x 2 sec contact with soldering iron/pin After two weeks back to 2 G limit NIKHEF card KSY44 solder test card 4 Measurements at 22 0 C Calibration done at 20, 24 0 C Phenomenon not seen in ATLAS: Time between soldering and calibration more than one month

21. Aging studies for ATLAS didn’t show the solder effect because the sensors were produced at NIKHEF, there was always a long ( > 1 month) delay between soldering and calibration Can the HGT2100 be used? Important points: short solder time heat sinking wait between soldering and calibration (heat treatment?) further investigation necessary What is the difference between KSY44 and HGT2100? HGT2100 is claimed to be GaAs, but shows much smaller planar Hall effect than KSY44 Is the HGT2100 similar to the KSY14 ? Ion implanted vs. MOVPE?

22. Which Hall probe to choose: Lakeshore HGT2100 very sensitive to soldering, maybe not usable more tests necessary KSY44 ok but no longer in production forgotten stock of about 300 ( bought before the 7000 of ATLAS) still available around the world e.g 1000 pcs for 7.5 euro/pc maybe new production GH-700 FW Bell stock problems under investigation Toshiba THS119 NIKHEF one B-sensor received to be tested