Lab calibration measurements with radioactive sources Julia - PowerPoint PPT Presentation

Lab calibration measurements with radioactive sources Julia Rietenbach 28. August 2012 Julia Rietenbach () Lab calibration measurements with radioactive sources 28. August 2012 1 / 17

Contents Motivation 1 Calibration Sources 2 Calibration measurements 3 Summary and Outlook 4 Julia Rietenbach () Lab calibration measurements with radioactive sources 28. August 2012 2 / 17

Motivation for the measurements Chip had taken data during Test Beam Pixel are not calibrated → position of the Landau distribution varied from pixel to pixel Julia Rietenbach () Lab calibration measurements with radioactive sources 28. August 2012 3 / 17

Motivation for the measurements Chip had taken data during Test Beam Pixel are not calibrated → position of the Landau distribution varied from pixel to pixel Each pixel needs to be calibrated individually → a lot of statistic is needed Julia Rietenbach () Lab calibration measurements with radioactive sources 28. August 2012 3 / 17

Motivation for the measurements Chip had taken data during Test Beam Pixel are not calibrated → position of the Landau distribution varied from pixel to pixel Each pixel needs to be calibrated individually → a lot of statistic is needed Use sources in the lab to calibrate the pixel Julia Rietenbach () Lab calibration measurements with radioactive sources 28. August 2012 3 / 17

Motivation for the measurements Chip had taken data during Test Beam Pixel are not calibrated → position of the Landau distribution varied from pixel to pixel Each pixel needs to be calibrated individually → a lot of statistic is needed Use sources in the lab to calibrate the pixel Raw Test Beam data can be recalibrated; TOT ↔ dE dx Julia Rietenbach () Lab calibration measurements with radioactive sources 28. August 2012 3 / 17

Julia Rietenbach () Lab calibration measurements with radioactive sources 28. August 2012 4 / 17

Calibration Sources Source Radiation Energy (keV) Intenstity (%) Source Radiation Energy (keV) Intenstity (%) Fe 55 Gamma/Xray 5,888 8,20 Cs 137 Beta 174,320 94,70 5,899 16,20 416,260 5,30 6,490 1,89 Sr 90 Beta 195,800 100,00 Electron 3,670 7,40 Am 241 Alphas 5388,000 1,66 26,400 0,78 5442,800 13,10 624,216 7,79 5485,560 84,80 655,668 1,40 5511,500 0,23 660,364 0,30 5544,500 0,37 Gamma/Xray 4,470 0,91 Electron 76,543 0,23 31,817 1,99 32,194 3,64 Gamma/Xray 13,900 37,00 36,304 0,34 26,345 2,27 36,378 0,67 59,541 35,90 37,255 0,21 C 14 Beta 49,470 100,00 661,657 85,10 Julia Rietenbach () Lab calibration measurements with radioactive sources 28. August 2012 5 / 17

Calibration Sources Source Radiation Energy (keV) Intenstity (%) Source Radiation Energy (keV) Intenstity (%) Cd 109 Electrons 2,610 167,10 Co 57 Electron 0,670 251,00 18,500 20,80 5,620 105,10 62,520 41,70 7,301 71,10 84,228 44,00 13,567 7,40 87,316 8,90 114,949 1,83 87,938 1,60 121,215 0,19 129,362 1,30 Gamma/Xray 2,980 10,30 Gamma/Xray 0,700 1,52 21,990 29,80 6,391 16,6 22,163 56,10 6,404 32,9 24,912 4,80 7,058 3,91 24,943 9,2 7,058 2,00 25,455 2,31 14,413 9,16 88,033 3,70 122,061 85,60 136,474 10,68 Julia Rietenbach () Lab calibration measurements with radioactive sources 28. August 2012 6 / 17

Absorption in Silicon Julia Rietenbach () Lab calibration measurements with radioactive sources 28. August 2012 7 / 17

Frames of different particle types Am 241 γ Source Am 241 α Source Fe 55 Source Cd 109 Source Cs 137 Source Julia Rietenbach () Lab calibration measurements with radioactive sources 28. August 2012 8 / 17

Laboratory Julia Rietenbach () Lab calibration measurements with radioactive sources 28. August 2012 9 / 17

Laboratory Julia Rietenbach () Lab calibration measurements with radioactive sources 28. August 2012 10 / 17

Calibration measurements Already finished most of the measurements Statistics for different sources: ◮ Am 241 gamma: all: 70052360 entries; single pixel: 43037750 entries ◮ Fe 55: all: 45305420 entries; single pixel: 44670740 entries ◮ Cd 109: all: 30787630 entries; single pixel: 20522860 entries next step fit peak for every pixel ◮ Stephane wrote a program which finds the peak automatically and makes the fit Julia Rietenbach () Lab calibration measurements with radioactive sources 28. August 2012 11 / 17

Julia Rietenbach () Lab calibration measurements with radioactive sources 28. August 2012 12 / 17

Julia Rietenbach () Lab calibration measurements with radioactive sources 28. August 2012 13 / 17

Single pixel occupancy for different Source Calibration measurment → noisy pixel on diagonal? Julia Rietenbach () Lab calibration measurements with radioactive sources 28. August 2012 14 / 17

TOT Spectrum from pixel on diagonal normal physics events → no noise Julia Rietenbach () Lab calibration measurements with radioactive sources 28. August 2012 15 / 17

TOT Spectrum of a single pixel noise peak always in the lowest entries to small to get masked → physical events still measurable Julia Rietenbach () Lab calibration measurements with radioactive sources 28. August 2012 16 / 17

Summary and Outlook Calibration measurements are mostly finished Continue the analysis, next steps will be ◮ use Stephane’s program to fit peak of each single pixel for the different sources ◮ Cross check the results with Am 241 α and Sr 90 source ◮ recalibrate the test beam data Julia Rietenbach () Lab calibration measurements with radioactive sources 28. August 2012 17 / 17