For ten days at the end of September, 1987, a group of about 75 scientists from 21 different countries gathered in a restored monastery on a 750 meter high piece of rock jutting out of the Mediterranean Sea to discuss the simulation of the transport of electrons and photons using Monte Carlo techniques. When we first had the idea for this meeting, Ralph Nelson, who had organized a previous course at the "Ettore Majorana" Centre for Scientific Culture, suggested that Erice would be the ideal place for such a meeting. Nahum, Nelson and Rogers became Co-Directors of the Course, with the help of Alessandro Rindi, the Director of the School of Radiation Damage and Protection, and Professor Antonino Zichichi, Director of the "Ettore Majorana" Centre. The course was an outstanding success, both scientifically and socially, and those at the meeting will carry the marks of having attended, both intellectually and on a personal level where many friendships were made. The scientific content of the course was at a very high caliber, both because of the hard work done by all the lecturers in preparing their lectures (e. g., complete copies of each lecture were available at the beginning of the course) and because of the high quality of the "students", many of whom were accomplished experts in the field. The outstanding facilities of the Centre contributed greatly to the success. This volume contains the formal record of the course lectures.

Inhaltsangabeand Fundamentals.- 1. Overview of Photon and Electron Monte Carlo.- 1.1 Introduction.- 1.2 Some History.- 1.3 Photons, Electrons and Medical Physics.- 1.4 Interesting Electrons.- 1.5 The Ultimate (Radiotherapy) Problem.- 1.6 Computer Technology.- 1.7 The Appeal of Monte Carlo.- 2. Multiple-Scattering Angular Deflections and Energy-Loss Straggling.- 2.1 Introduction.- 2.2 Elastic-Scattering Cross Section.- 2.2.1 Factorization.- 2.2.2 Spin and Relativity Effects.- 2.2.3 Screening Effects.- 2.2.4 Characteristic Screening Angle.- 2.2.5 Calculations by the Partial-Wave Method.- 2.2.6 Comparisons of Elastic-Scattering Cross Sections.- 2.2.7 Molecular and Solid-State Effects.- 2.3 Calculation of Multiple-Scattering Deflections.- 2.3.1 Molière Multiple-Scattering Distribution.- 2.3.2 Goudsmit-Saunderson Multiple-Scattering Distribution.- 2.3.3 Contribution of Inelastic Collisions to Multiple Scattering.- 2.3.4 Number of Elastic Collisions and Mean Deflection Angle.- 2.3.5 Comparison of Multiple-Scattering Distributions.- 2.4 Energy-Loss Straggling.- 2.4.1 Landau's Distribution: Applicability, Refinements.- 2.4.2 More Elaborate Treatment of Straggling.- 2.4.3 Energy-Loss Straggling in Water.- 3. Electron Stopping Powers for Transport Calculations.- 3.1 Introduction.- 3.2 Definition of Stopping Power.- 3.3 Continuous-Slowing-Down Approximation.- 3.4 Stopping-Power Formulas and Tables.- 3.5 Mean Excitation Energies.- 3.5.1 I-Values from Stopping-Power Data.- 3.5.2 I-Values from Photon Cross Sections.- 3.5.3 Survey of Mean Excitation Energies for Elements.- 3.5.4 Mean Excitation Energies for Compounds.- 3.6 Density-Effect Correction.- 3.7 Comparisons with Experiments.- 3.8 Stopping-Power Ratios.- 3.9 Stopping Powers at Low Energies.- 3.10 Concluding Remarks.- 4. Cross Sections for Bremsstrahlung Production and Electron-Impact Ionization.- 4.1 Introduction.- 4.2 Bremsstrahlung Production.- 4.2.1 Electron-Nucleus Bremsstrahlung.- 4.2.2 Electron-Electron Bremsstrahlung.- 4.2.3 Comparisons of Calculated and Measured Cross Sections.- 4.2.4 Radiative Stopping Power.- 4.2.5 Positron Bremsstrahlung.- 4.3 Electron-Impact Ionization.- 4.3.1 Cross-Section Formulas.- 4.3.2 Input Data.- 4.3.3 Illustrative Examples.- 5. Electron Step-Size Artefacts and PRESTA.- 5.1 Introduction.- 5.2 Electron Step-Size Artefacts.- 5.2.1 What Is An Electron Step-Size Artefact?.- 5.2.2 Path-Length Correction.- 5.2.3 Lateral Displacement.- 5.2.4 Boundary Crossing.- 5.3 PRESTA.- 5.3.1 The Elements of PRESTA.- 5.3.2 Constraints of the Molière Theory.- 5.3.3 PRESTA's Path-Length Correction.- 5.3.4 PRESTA's Lateral-Displacement Algorithm.- 5.3.5 Accounting for Energy Loss.- 5.3.6 PRESTA's Boundary-Crossing Algorithm.- 5.3.7 Caveat Emptor.- 6. 20 MeV Electrons on a Slab of Water.- 6.1 Introduction.- 6.2 A Thin Slab.- 6.2.1 The CSDA Calculation.- 6.2.2 More Realistic Calculations.- 6.3 A Thick Slab.- 6.3.1 Typical Histories.- 6.3.2 Depth-Dose Curves.- 6.3.3 Fluence vs Depth.- 6.4 Conclusions.- The Eltran System.- 7. An Overview of ETRAN Monte Carlo Methods.- 7.1 Introduction.- 7.2 Monte Carlo Methods.- 7.2.1 Photon Transport.- 7.2.2 Electron Transport.- 7.3 Organization and Description of the Code System.- 7.3.1 Data Preparation.- 7.3.2. Monte Carlo Calculations.- 7.4 Future Improvements.- 8. ETRAN - Experimental Benchmarks.- 8.1 Introduction.- 8.2 Comparisons.- 8.3 Discussion.- 9. Applications of ETRAN Monte Carlo Codes.- 9.1 Introduction.- 9.2 Response of Photon Detectors for Spectrometry.- 9.2.1 NaI Detectors.- 9.2.2 High-Purity Ge Detectors.- 9.3 Space Shielding Calculations.- 9.4 Bremsstrahlung Beams for Radiation Processing.- 9.5 Liquid-Scintillation Counting of Beta Emitters.- The Integrated Tiger Series.- 10. Structure and Operation of the ITS Code System.- 10.1 Introduction.- 10.2 History of the TIGER Series.- 10.3 Structure of the ITS Code System.- 10.3.1 The Source Files.- 10.3.2 The UPEML Processor.- 10.4 Operation of the ITS Code System.- 10.4.1 Input.- 10.4.2 Outp