On behalf of joint ITEP / IHEP team: A. Arefiev, N. Filimonov, T. Kvaratskheliya, I. Machikhiliyan, P. Shatalov, T. Zakoryuchkina, A. Zhokhov, S. Zvyagintsev ECAL: status and plans Irina Machikhiliyan, Outline:  A-side  C-side  Lab activities  Further plans

ECAL A-side Irina Machikhiliyan,  C-W modification is almost finished:  Outer / Middle region are done;  Few boxes are still missing in the Inner section; Is it possible to start the installation this week in order to start the commissioning in the end of the next week / beginning of the week after the next?  Last week: installation and check of the HV-boxes system:  Successfully passed test procedure  For a moment is disconnected from power supplies (safety for the future installation of PM/C-W) Green: ready for installation; White: to be done;

Commissioning of the ECAL C-side Irina Machikhiliyan, Took place in the week of 2 – 8 Feb Reference data samples: #43821 PM HV nominal, LED LV = (nominal + 1V), 1K of 5 TAE events, LED trigger rate 56 Hz (taken ) #43822 PM HV nominal, LED LV nominal, 1K of 5 TAE events, LED trigger rate 56 Hz (taken ) #43815 PM HV nominal, LED LV nominal, ~52.5K of events, LED trigger rate 3 Hz, 5 TAE events (almost 5 hours stability run, taken )

Irina Machikhiliyan, Test program: -Check of the functionality of PMs / LEDs: several cables were not plugged, fixed; 5 doublets PM/C-W showed small C-W noise tails, replaced; -Connectivity test (swapped cables): some swapped control cabling in the Inner section, fixed; -Pulser test to check connectors quality (thanks to Jacques): 3 connectors on signal cables on PM side, replaced; -Adjustment of integrators; -Update of connectivity in Database; -~5 hours stability measurements; Remaining problems / tasks:  Cells O 15/37(09/11/31) and M 01/29 (11/08/09) – problem on FEB side according to pulser test (Jacques knows);  Couple of cells showed instability: to be watched further to understand the reason;  One LED (C1.16.1) is unstable (problems is known since the last year, LED driver will be replaced); For a moment:  LED intensities are not optimally adjusted. It does not make sense to do it now: they will be tuned after the calibration of PM gains will be done;  PIN system functionality is not yet checked. To be done (data are collected, to be analyzed); Commissioning of the ECAL C-side

Irina Machikhiliyan, r.m.s. of pedestal distribution Relative signal deviation, 4.8 hours Relative signal deviation, ~4 hours Response on LED, nominal settings; (!) 7 cells: amplitude is below 150 counts (!)

Irina Machikhiliyan,  Equipment used:  High voltage probe TENMA FLUKE 45 MULTIMETER  Both checked with NIM Power Supplies - N470 in the range of output voltages 0÷1.3kV: accuracy of the measurement is on the level of 0.1%  Measurement conditions:  14 C-W bases of HCAL_mc design  10 C-W bases of ECAL_mc design  PM control voltage is in the range 0÷3.8 V  Medium voltage setting +96V Lab measurements: final dependence of output C-W HV on the control voltage

Irina Machikhiliyan, Lab measurements: comparison of designs HCAL_mcECAL_mc No difference between HCAL_mc and ECAL_mc was observed except for the first point

Irina Machikhiliyan, Lab measurements: final dependence of output C-W HV on the control voltage HCAL_mc+ ECAL_mc The final formula is: HV(V) = *Vctrl (V) For Vctrl ~ 3.5V medium voltage setting must be +90V +80V is not enough for “cosmics”

Irina Machikhiliyan, Lab measurements: reproducibility of output HV over different C-W In the ECAL operating range (~1 ÷ 2V of Vctrl): < 0.5% in HV or <3.2% in gain Contribution from HV-box (r.m.s. of Vctrl): < 0.36% in Vctrl or < 2.3% in gain In the ECAL operating range: < 1.6% in HV or <10.2% in gain These numbers define the precision of the calibration which can be achieved by “hardware” methods α (HAMAMATSU) r.m.s., VoltsMax spread, Volts

Further plans Irina Machikhiliyan,  This / next week: installation of PM/C-W on A- side;  Until mid. of March: A-side PM/C-W commissioning;  Starting from second half of March: (a)In the lab: modification of spare C-W + repair; (b)On ECAL detector: calibration of PM gain by photo-statistics; adjustment of LED intensities; etc;