Chapter I. THE THEORY OF THE ASPIRATION
METHOD UNDER IDEAL CONDITIONS

§ 1. Air ions (1)

§ 2. Velocity field of air ions (4)

§ 3. Arrangement of an aspiration counter and the principle
of measurement of the air-ion spectrum (6)

§ 4. Integral counter (8)

§ 5. Solution of the equation of the integral counter (11)

§ 6. Various integral counter types (14)

§ 7. Differential counters of the first order (17)

§ 8. Differential counter of the second order (22)

§ 9. Counters with several collector plates (25)

§ 10. Counters with interplate air mixing (29)

§ 11. Measurement of the space charge density (32)

§ 12. Modulated counters (34)

Chapter II. DEVIATIONS FROM IDEAL CONDITIONS

§ 13. Factors causing disturbances and systematic measurement
errors (39)

§ 14. The edge effect (41)

§ 15. Results of the experimental investigation of the edge effect
(45)

§ 16. Effect of space charge on measurement results (50)

§ 17. Measurement methods based on the utilization of the electric
field of the space charge (57)

§ 18. The electrode effect (60)

§ 19. Diffusion of air ions (64)

§ 20. Turbulent mixing of air in measuring capacitor (71)

§ 21. Results of the experimental investigation of the effect
of turbulence (75)

§ 22. Long measuring capacitor with a turbulent air flow (84)

§ 23. The asymmetry of the measuring capacitor and the effect
of gravitation of air ions (87)

§ 24. Adsorption of air ions (92)

Chapter III. PARAMETERS AND DESIGN PRINCIPLES
OF ASPIRATION COUNTERS

§ 25. Classification of counter circuit arrangements (100)

§ 26. Current measurement by the charge accumulated in a capacitor
(103)

§ 27. Current measurement based on the voltage drop across a resistance
(106)

§ 28. Sensitivity of the integral counter (110)

§ 29. Calculation of air-ion spectral characteristics (113)

§ 30. Assessment of random errors in measuring the characteristics
of the air-ion spectrum (118)

§ 31. Elimination of the effect of random voltage fluctuations
on the measurement results (124)

§ 32. Prevention of the edge effect (128)

§ 33. Methods of determination of the effective capacitance of
the measuring capacitor (132)

§ 34. Principles of the selection of the parameters and operating
conditions of the integral counter (136)

§ 35. Brief survey of the designs of air-ion aspiration counters
(143)

§ 36. Description of a universal integral air-ion counter (149)

SUPPLEMENTS

List of symbols (159)

Appendix I - Special factors in measurement at high altitudes (161)

Appendix II - Systems of units (165)

Bibliography (166)

List of Abbreviations (200)