HCAL1 Status 2004 Oleg Gavrishchuk, JINR, Dubna 1. HCAL1 performance in 2004 General design High Voltage system LED monitoring 2. Stability in 2003 Led monitoring Muon peak position 3. On-line reference plots 4. Energy response in HCAL1 efficiency in Planning 2004

O.GavrishchukCOMPASS TB, CERN, April 2, HCAL1 general design Matrix setup of 28v20 cells 480 cells 150x150mm**2 Total size: 4200x3000mm**2 Window size: 1200x600mm**2 (8x4 cells) Total Weight: 83 tonn Moving range: +/-2.5m HCAL1 Status 2004

O.GavrishchukCOMPASS TB, CERN, April 2, High Voltage layout H/V interface is controlled by pccofe m flat cable (50 pairs) transfer the commands from H/V interface to receiver in the CAMAC crate Receiver distribute the commands to 7 Data and 1-Chip-select boards Power suppliers: +100V DC, load current 140mA per 480 PM +6V DC, load current 8A (6A for 480 PM) -6V DC, load current 3A HCAL1 Status 2004

O.GavrishchukCOMPASS TB, CERN, April 2, LED monitoring layout Blue LED (470nm) high (ultra bright) luminosity used for 480 HCAL1 Photo- multipliers PM-84 Light intensity controlled by avalanche PIN diode Led generator pulsed out of Spill with frequency selected before start of Run HCAL1 Status 2004

O.GavrishchukCOMPASS TB, CERN, April 2, LED reference plots in Sum HCAL1 Led amplitude histogram 2.Pin Diode amplitude histogram 3.LED amplitude vs HCAL1 560 channels (matrix 28x20) 4.X-Y amplitude be- plot Ampl. VS N_chann Sum_LED Pin Diode_amp HCAL1 Status 2004

O.GavrishchukCOMPASS TB, CERN, April 2, LED amplitude in data taking periods P1A_P1H Pin diode amplitude 2.HCAL1 corrected on PIN 3.HCAL1 LED with-out PIN corrections LED monitoring system indicate: 1.HCAL1 amplitude decrease on 8% from P1A to P1H data taking periods. 2.HCAL1 amplitude is practically stable HCAL1 Status 2004

O.GavrishchukCOMPASS TB, CERN, April 2, Start of Run 2003: Mean A=57.6End of Run 2003: Mean A=53.6 HCAL1 Status 2004

O.GavrishchukCOMPASS TB, CERN, April 2, ON-Line Reference Plots: 1.Hits distribution. 2.Amplitude vs channels. 3.Amplitude distribution. 4.Noise distribution 5.All events hits histogram 6.Frequency vs HCAL1 560 channels (matrix 28x20) 7.Total HCAL1 amplitude 8.Hits for events with amplitude cut of 20 ADC channels.

O.GavrishchukCOMPASS TB, CERN, April 2, Fig.1.Distribution of tracks with P>1Gev/c extrapolated to the HCAL1 outside the central window (P1D 2002). Fig.2.The ratio of the number of HCAL1 clusters to the number of associated tracks extrapolated to the HCAL1 outside the central window as a function of the track momentum. All tracks from Fig.1 are taken for this plot. Fig.3.The same as in Fig.2 but for associated tracks with z-coordinate registered in the last tracking chamber close to HCAL1 (Zlast>900). HCAL1 Status 2004

O.GavrishchukCOMPASS TB, CERN, April 2, HCAL1 Status 2004 Momenta-HCAL1 Energy distribution for P1D 2003.

O.GavrishchukCOMPASS TB, CERN, April 2, Track momentum – E HCAL1 clusters normalized to E clusters For P1D 2003 HCAL1 Status 2004

O.GavrishchukCOMPASS TB, CERN, April 2, HCAL1 planning in General test without beam: 5-10 April 1.H/V controll 2.LED monitoring 3.Noise testing with Random Trigger 4.ADC test (pedestals and signals) 2.Light leakage and H/V noise decreasing11-20 April 1.H/V base grounding 2.LED’s fiber isolation 3.Adjust the Calibration Trigger delay---20 April 1.Timing controll in on-line 4.HCAL1 test with Calibration Trigger20-28 April 1.Time for individual channels stability 2.LED amplitudes stability 5.HCAL1 should be ON from 28 April – 05 October HCAL1 Status 2004

O.GavrishchukCOMPASS TB, CERN, April 2, Upper windows part consist from 4 rows by 10 modules which are fixed by help steel plates on front and back HCAL1 sides. The PM tubes and H/V base are placed inside of steel tubes HCAL1 Status 2004

O.GavrishchukCOMPASS TB, CERN, April 2, Design of the HCAL1 module (cell) HCAL1 Status 2004

O.GavrishchukCOMPASS TB, CERN, April 2, HCAL1 Status 2004 HCAL1 energy spectra for P2E 2002.

O.GavrishchukCOMPASS TB, CERN, April 2, HCAL1 Status 2004 HCAL1 energy response for P2E 2002.