M.D. Nov 27th 2002M0' analysis workshop1 Monitoring system : lessons from M0’  Contents : Monitoring electronics Laser APD electronics Conclusions & requirements for 2003

M.D. Nov 27th 2002M0' analysis workshop2 Monitoring system description

M.D. Nov 27th 2002M0' analysis workshop3  MEM stability : Use self measurement of Vinj (stabilized at / year)  Stability better than 50  V / 500 mV over 1 month Monitoring electronics

M.D. Nov 27th 2002M0' analysis workshop4  FE-Asic stability : Use electronics injection pulse  Rather good stability over 2 months (1/1000 drift) Monitoring electronics 2002/08/08

M.D. Nov 27th 2002M0' analysis workshop5  PN stability : Compare PN0 with PN2 (level1 fan-out) :  Not stable at all (2.5 % over 2 months) ! Monitoring electronics 2002/08/08

M.D. Nov 27th 2002M0' analysis workshop6  PN stability : Look in archives : Accelerated aging in oven in 2001  degrees  PN2 should have never been put on M0’ !  Zero quality control on PN diodes at this time. Monitoring electronics 2001/03/06 PN0PN2 PN3PN1

M.D. Nov 27th 2002M0' analysis workshop7  Energy stability :  Huge variation with time (short term and long term)  “Raison d’être” of monitoring system  OK Laser

M.D. Nov 27th 2002M0' analysis workshop8  Pulse width stability :  Huge variation with time (short term and long term)  Huge effect on APD/PN0  Need to be monitored ! Laser d(fppa)/d  Nanogreen laser Particles Quantronix laser nominal Quantronix laser 2002

M.D. Nov 27th 2002M0' analysis workshop9  Electronics stability : Small dependence on T  No problem with present regulation Dependence with LV :  No significant change in gain up to now  Pedestals affected  Regular pedestal runs Dependence with VFE mode :  Pedestal affected Free vs Forced mode  Hard to monitor for hidden gains (G9, G5 and G1 in frre mode) Dependence with laser energy  Pedestals affected  Compute dynamic pedestals Dependence with laser pulse width  Convolution with FPPA shaping time  Need to monitor laser pulse width event by event APD line

M.D. Nov 27th 2002M0' analysis workshop10  Electronics stability : Dependence with HV :  A priori big dependence of APD gain with HV  Need to checked stability of APD response with present HV system On good channels : VFE electronics  = 1.4/1000

M.D. Nov 27th 2002M0' analysis workshop11  Back to crystal 1142 : Calibration drift by 5-6/1000 in 2 weeks :  Compare with electron runs APD line Calibration 120 GeV

M.D. Nov 27th 2002M0' analysis workshop12 Conclusions  Monitoring system : Need to implement an efficient quality control on PN diodes Electronics very stable but :  Need to clarify pedestal puzzle (fppa 200x) Need to monitor laser pulse width event by event  Requirement for 2003 Residual instabilities seems physical  Parasitic irradiations  HV fluctuation ?  Red laser required for next year To-do :  Reprocess irradiation data with all the correction  Should be able to get S/R curves with PN diodes as only reference  Fine study of HV data