Introduction Publicatiins and Reports 3 Administrative and Service Personnel 5 Research Projects I. A. B. C. D. E. f. IL, Microwave and Physical Electronics Construction of 5 mm. Oxford Type Tube High Power 8-Band Magnetron Magnetron Theory Research Cathode Research Electrometer Tube Development The Transmission of the Photo-effect in Silicon Microwave Physics A. Radio Frequency Spectroscopy 1. Absorption of Electromagnetic Waves in Oxygen 2. Measurement of Microwave Absorption Spectra of Gases 3. Caesium Hyperfine Structure 4. Molecular Beams 3. Gas Discharge Research Report 1. Low Pressure Discharges 2. Microwave Spark Breakdown 0. Low Temperature Research 7 8 9 14 17 19 22 24 26 28 81 1. Helium Cryostat 32 2. 3. 4. Superconductivity of Lead at 8 am Wavelength Resistance of Germanium Nuclear Resonance at Low Temperatures and Strong Magnetic Fields' 37 39 5. Theoretical Studies D. Ferromagnetism at Microwave frequencies III. Modern Electronic Techniques Applied to Physics and Engineering A. Studies Leading to the Design of a Microwave Accelerator B. Ultrasonics Research Program C. High Speed Oscilloscope and High Voltage Pulse Measuring Techniques D. High Pressure Ionization Chamber E. 7 Cyclotron Project 39 39 41 42 43 48 50 51 Liquid Pilled Chamber to be Used in the Photographing of Very High Energy Ionizing Particles G. Measurement and Control of Deionisation Time in Thyratrons H. Experimentation in Photoelectric Spectrophotometry 52 52 55 I. 59 1. IV. Biophysics Project Communications and Related Projects Modulation Studies: Spectrum Utilization. Efficiency of Power Utilization, Signal to Noise Ratios 3. Stabilized Oscillator Problems C. Multipath Transmission A. D. E. Impulse Interference Circuit Problems 1. Study of Waveguide with Dissipative Walls 2. Magic-T Problems 3. Miscellaneous Waveguide Problems 4. Transient Phenomena in Waveguides V. Aids to Computation A. Shaft Position Indicator, Reversible Counters 60 63 64 65 65 67 68 69