ECFA-Calo 3-Apr-03S. Němeček: Photodetectors for Tile-HCAL prototype Photodetectors for Tile-HCAL prototype 1.Only APD ( FZU= APD+RF-Preampli) 2.I-V and C-V characteristics 3.LED response of APD and of PMT measurement of S8550 matrix and single APD 4.1/G*dG/dT, 1/G*dG/dV – compare E1 to 3x3 5.16ch Preampli PCB and single APDs 6.Conclusions

ECFA-Calo 3-Apr-03S. Němeček: Photodetectors for Tile-HCAL prototype APD + Preampli

ECFA-Calo 3-Apr-03S. Němeček: Photodetectors for Tile-HCAL prototype corrected HV bias 385.5V corrected HV bias 387.5V pixel E1 Beam test DESY Aug02

ECFA-Calo 3-Apr-03S. Němeček: Photodetectors for Tile-HCAL prototype Thanks to ATLAS-Praha, ID-pixels group

ECFA-Calo 3-Apr-03S. Němeček: Photodetectors for Tile-HCAL prototype Thanks to ATLAS-Praha, ID-pixels group

ECFA-Calo 3-Apr-03S. Němeček: Photodetectors for Tile-HCAL prototype Thanks to ATLAS-Praha, ID-pixels group

ECFA-Calo 3-Apr-03S. Němeček: Photodetectors for Tile-HCAL prototype Thanks to ATLAS-Praha, ID-pixels group: KEITHLEY K237 HV / I Source-Measurement, Agilent (HP) 4284A LC-meter, 10 kHz

ECFA-Calo 3-Apr-03S. Němeček: Photodetectors for Tile-HCAL prototype Measurement Setup APD + Preampli 24*Npe PM Npe NγNγ 3*Nγ Q PM σ PM, Q AP σ AP Npe = 2 /  PM 2 G PM =  PM 2 / (e- * ) G AP = / (e- *24*Npe) G AP = ( /(e-*24)) *  PM 2 / 2 G AP = ( / (24* )) * G PM = Np.e. *Gain * e- QE(PM) = 10% QE(APD) = 80% Green light 520nm LED Checked by fibres swap

ECFA-Calo 3-Apr-03S. Němeček: Photodetectors for Tile-HCAL prototype S/N = 6.7 S/N = 8.6

ECFA-Calo 3-Apr-03S. Němeček: Photodetectors for Tile-HCAL prototype +2.5% -2.5%

ECFA-Calo 3-Apr-03S. Němeček: Photodetectors for Tile-HCAL prototype F = difference of APD noise from one expected based on Poissonian statistics 2 / (  AP 2 -  AP Noise 2    F  AP Noise … measured as pedestal width (LED off)    24*Npe ( APD value calculated from PMT one)

ECFA-Calo 3-Apr-03S. Němeček: Photodetectors for Tile-HCAL prototype Measured Results S8550, E1U = 388 VU = 390 V G AP M APD APD 3x3U = 399 VU = 424 V G AP M APD M APD =G AP / ( 20 * 100)

ECFA-Calo 3-Apr-03S. Němeček: Photodetectors for Tile-HCAL prototype

ECFA-Calo 3-Apr-03S. Němeček: Photodetectors for Tile-HCAL prototype Gain dependence on temperature

ECFA-Calo 3-Apr-03S. Němeček: Photodetectors for Tile-HCAL prototype Gain dependence on voltage

ECFA-Calo 3-Apr-03S. Němeček: Photodetectors for Tile-HCAL prototype Gain dep. on U, compare E1 to 3x3 Pixel E1 Single APD 3x3 mm 2

ECFA-Calo 3-Apr-03S. Němeček: Photodetectors for Tile-HCAL prototype PCB 16 ch. Preampli (FZU)

ECFA-Calo 3-Apr-03S. Němeček: Photodetectors for Tile-HCAL prototype 4. Conclusions I-V and C-V characteristics were measured for single APD3x3mm 2 Gain and Excess Noise Factor F were calculated from simultaneous measurement of APD and PMT response to LED –Ratio APD/PMT response within ±2.5% –F = ~4 for single APD, better than F= ~8 for matrix (pixel E1) Gain dependence on temperature 1/G*dG/dT = ~12% at maximal gain of E1 pixel of matrix APD (measured in range 11 to 26 °C ) Gain dependence on voltage 1/G*dG/dV is again better for single APD, 15% at maximal gain –Power supply with ΔV/V=1.E-4 gives 1% of Gain stability –Possibility of voltage-temperature regulator is under study A prototype of PCB of 16 channels preamplifier was produced –Adaptor to single APD (instead of matrix) is under way