The purpose of this report is to compare multi-layer insulation and liquid nitrogen shielding as methods of insulating the 80-inch Liquid Hydrogen Bubble Chamber.

Reliability of individual components and the ability to produce refrigeration even if one or two of these components should be in operable are the prime design parameters of this cycle. Each component was looked at with these two parameters in mind and any item that had obvious objections was either rejected or backed up with another piece of equipment. Along this line, you will notice (refer to line schematic) two hydrogen compressors and two nitrogen compressors; for full capacity all are required. However, in the event of the loss of use of one of these compressors, it will still be possible to produce at least 50% of the rated capacity. To eliminate outside influences, the cycle was designed around what may be called a closed cycle cascade system; with the assumption that there is no loss of power, cooling water, the equipment can run indefinitely. The nitrogen and hydrogen cycles are of the Simple Linde type with pre-cooling making use of the Joule-Thompson Effect for the refrigeration produced. The low-temperature components of the cycle have no moving parts other than valves, consisting entirely of counter-flow heat exchangers to lower the temperature of the incoming high-pressure gas to a level where …

On the basis of measurements made upon analogues of the proposed magnet, it was decided that the distribution of ampere-turns between the two exciting coils should be in a ratio of about 1:33:1. This distribution is expected to minimize the variation of the magnetic field intensity over the depth. of the chamber. Simplicity of construction demands that there be an integral number of turns in each layer of conductors. If no water connections are to be made at the inside of the coils, each coil must contain an even integral number of layers.