1. Effective Depletion Depth JC & Marina

2. 04/30/01Jianchun (JC) Wang2 Depletion Depth Methods FPIX0 pstop at 30° X inc 1 2 3 4 Depth: d  XiXi

3. 04/30/01Jianchun (JC) Wang3 Existing Problem Method 1  Falling edge is not at the effective depth  The difference is threshold-dependent  For ideal case ( threshold low, no diffusion, no noise ), difference = pitch/(2  tan  ) = 43  m  Absolute alignment is needed (can be avoided with both edges) Thickness: 300  m Track angle: 30° Threshold: 2500 e 500 e Both methods affected by uncertainty of  Method 2  Slightly depends on threshold  Distribution is not symmetric, difficult to determine peak position

4. 04/30/01Jianchun (JC) Wang4 Study Both Edges FPIX0 pstop at 30° span (FWHM) = 329.9  1.2  m

5. 04/30/01Jianchun (JC) Wang5 Monte Carlo Simulation  MC simulation with different thickness ( 2  m step)  The difference between span and the thickness is a constant with small variation of thickness FPIX0-pstop

6. 04/30/01Jianchun (JC) Wang6 Results of Method 1 Thickness: FPIX0-pstop: 292.7  1.2  m FPIX1-pstop: 295.8  0.9  m FPIX0-pstop FPIX1-pstop Large systematic errors: Threshold: 18  m /1000 e Angle  : 12  m / 1°

7. 04/30/01Jianchun (JC) Wang7 Method 2 Simulation  Method 2 is more complicated even though the sensitivity may be small  Correction correlated with fraction of different cluster size  Threshold, nominal thickness, angle of track all affects the correction

8. 04/30/01Jianchun (JC) Wang8 Result of Method 2 FPIX0-pstop Peak position: 295.6 ±1.0  m Thickness: 305.0±1.0  m Systematic error not estimated Difference between two methods: 12.3  m

9. 04/30/01Jianchun (JC) Wang9 Summary  Two methods of effective depletion depth studied  In method 1, both edges are fit and the span is used to estimate the depth, correction is derived from MC, the depth are: 292.7±1.2  m (FPIX0-pstop), 295.8±0.9  m (FPIX1-pstop)  In method 2, the peak position is used to estimate the depth, correction is derived from MC, the depth is 305.0±1.0  m for FPIX0-pstop  The systematic errors are not derived but an estimation is given  The difference between two methods is 12.3  m