Signal Processing for Radiation Detectors

MOHAMMAD NAKHOSTIN earned his PhD in 2008 from the department of Quantum Science and Energy Engineering at the Tohoku University, Sendai, Japan, where he worked as assistant professor till 2010. He is currently a research fellow at the University of Surrey, UK. He has worked on the development of gaseous, semiconductor, and scintillation detectors and their readout electronics systems for a wide range of applications from plasma neutron diagnosis to medical imaging.

Preface xi

Acknowledgement xii

1 Signal Generation in Radiation Detectors 1

1.1 Detector Types 1

1.2 Signal Induction Mechanism 2

1.3 Pulses from Ionization Detectors 9

1.4 Scintillation Detectors 57

References 72

2 Signals, Systems, Noise, and Interferences 77

2.1 Pulse Signals: Definitions 77

2.2 Operational Amplifiers and Feedback 80

2.3 Linear Signal Processing Systems 83

2.4 Noise and Interference 101

2.5 Signal Transmission 120

2.6 Logic Circuits 130

References 133

3 Preamplifiers 135

3.1 Background 135

3.2 Charge-Sensitive Preamplifiers 137

3.3 Current-Sensitive Preamplifiers 159

3.4 Voltage-Sensitive Preamplifiers 162

3.5 Noise in Preamplifier Systems 163

3.6 ASIC Preamplifiers 176

3.7 Preamplifiers for Scintillation Detectors 182

3.8 Detector Bias Supplies 186

References 187

4 Energy Measurement 191

4.1 Generals 191

4.2 Amplitude Fluctuations 194

4.3 Amplifier/Shaper 203

4.4 Pulse Amplitude Analysis 234

4.5 Dead Time 244

4.6 ASIC Pulse Processing Systems 249

References 256

5 Pulse Counting and Current Measurements 261

5.1 Background 261

5.2 Pulse Counting Systems 263

5.3 Current Mode Operation 274

5.4 ASIC Systems for Radiation Intensity Measurement 286

5.5 Campbell’s Mode Operation 289

References 293

6 Timing Measurements 295

6.1 Introduction 295

6.2 Time Pick-Off Techniques 300

6.3 Time Interval Measuring Devices 320

6.4 Timing Performance of Different Detectors 330

References 345

7 Position Sensing 349

7.1 Position Readout Concepts 349

7.2 Individual Readout 353

7.3 Charge Division Method 357

7.4 Risetime Method 373

7.5 Delay-Line Method 375

References 380

8 Pulse-Shape Discrimination 383

8.1 Principles of Pulse-Shape Discrimination 383

8.2 Amplitude-Based Methods 386

8.3 Zero-Crossing Method 393

8.4 Risetime Measurement Method 399

8.5 Comparison of Pulse-Shape Discrimination Methods 401

References 404

9 Introduction to Digital Signals and Systems 407

9.1 Background 407

9.2 Digital Signals 408

9.3 ADCs 414

9.4 Digital Signal Processing 418

References 438

10 Digital Radiation Measurement Systems 441

10.1 Digital Systems 441

10.2 Energy Spectroscopy Applications 448

10.3 Pulse Timing Applications 472

10.4 Digital Pulse-Shape Discrimination 483

References 498

Index 503