Cover; Contents; Contributors to Volum 15; Preface; Chapter 1. Atomic Beam Frequency Standards; I. Introduction; II. Atomic Hyperfine Structure; III. The Vector Model; IV. The Breit-Rabi Formula; V. The Atomic Beam Spectrometer; VI. The Transition Process; VII. Measurement Uncertainties; VIII. Standard Frequency Comparisons Between Cesium Standards via Propagation Data; IX. Thoughts on Future Developments; Appendix; References; Chapter 2. Masers and Other Quantum Mechanical Amplifiers; I. Introduction; II. Ammonia Beam Masers; III. A Paramagnetic Atomic Beam Maser

IV. The Paramagnetic Two-Level Solid State MaserV. The Three-Level Solid State Cavity Maser; VI. Traveling Wave Masers; VII. Maser Systems at 50 kMc/sec and Higher Frequencies; VIII. Recent Progress; IX. Conclusions; References; Chapter 3. Relaxation in Diluted Paramagnetic Salts at Very Low Temperatures; I. Introduction; II. The Energy Levels of a, Paramagnetic Ion; III. Paramagnetic Relaxation; IV. Experimental Methods; V. Experimental Results; VI. Conclusions; References; Chapter 4. Millimeter Wave Techniques; I. Introduction; II. Transmission Methods; III. Measurement Techniques

IV. Total Reflection StudiesV. Discussion; References; Chapter 5. The Distribution of Electrons in the Ionosphere; I. Introduction; II. Physical Processes Determining the Electron Distribution; III. Methods for Measuring Electron Density; IV. Propertiesof the Steady Electron Distribution; V. Conclusion; References; Chapter 6. The Autodyne as Applied to Paramagnetic Resonance; I. Introduction; II. Historical Review; III. The Paramagnetic Sample and the Tank Circuit of the Oscillator; IV. Analysis of the Oscillator Circuit; V. Time Dependent Signals; VI. The Super-Regenerative Detector

VII. Practical ConsiderationsReferences; Author Index; Subject Index; Cumulativb Author Index, Volumes 1-15; Cumulative Subject Index, Volumes 1-16