ORTEC 473 - Page 4

ILLUSTRATIONS
Fig. b.1. Constant Fraction Trigger Timing for Two Different Input Pulse Amplitudes G
Fig. 5.2. Simplified Block Diagram of the 473 Constant Fraction Discriminator 7
Fig. 6.1. A System for Gamma-Gamma Lifetime Measurement 10
Fig. 6.2. Timing Over a Narrow Dynamic Range with the System of Fig. 6.1 10
Fig. 6.3. Plot of Time Resolution vs Dynamic Range Using RCA 8850 Photomultiplier Tube 11
Fig. 6.4. Plot of Time Resolution vs Dynamic Range Using RCA 8575 Photomultiplier Tube 11
Fig. 6.5. Typical Timing Spectrum Over a Wide Dynamic Range (50:1) with Nal(TI) 12
Fig. 6.6. Plot of Time Resolution vs Dynamic Range Using Nal(TI) and RCA 8575 PMT 12
Fig. 6.7. Gamma-Gamma Coincidence System Using
Plastic Scintillator and a Large Gel Li) Coaxial Detector 13
Fig. 6.8. Timing Spectrum for a Narrow Dynamic Range (1.1:1) for the System of Fig. 6.7 13
Fig. 6.9. Timing Spectrum for a Wide Dynamic Range (10:1) for the System of Fig. 6.7 13
Fig. 6.10. The Effect of 473 Threshold Setting on the Apparent Efficiency of Different Ge(Li) Detectors . . 14
Fig. 7.1. Test Setup for Leading Edge Discriminator Mode Calibration 16
Fig. 7.2. Test Setup for Scintillation Mode Walk Test 17
Fig. 7.3. Test Setup for Nal Mode Walk Test 18
Fig. 7.4. Test Setup for Ge(Li) Mode Walk Test 19