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The beam-dump kicker magnets are located in the final focus region and, in conjunction with septum magnets, extract the beams after they have passed the interaction point (IP) and direct them to their respective dumps. Two schemes for these kickers have been under consideration; ferrite transmission line magnets utilizing technology common with damping rings and positron target kickers, and current loop magnets which are possible only for the dump kickers, where the rise time of the magnetic pulse can be comparatively longer; approximately 400 nanoseconds as compared with 50 nanoseconds for the others. A prototype ferrite kicker has been built and is undergoing tests. Since the current loop requires lower voltage and power plus some additional savings in cost, we decided to build and test a prototype. This note describes in detail an optimized design for the current loop magnets and their associated pulse circuitry.

A streamer chamber in an axial magnetic field is discussed as a possible central track detector around which additional detectors, such as shower counters, Cherenkov counters, time-of-flight counters, etc., can be assembled.

Application of the liquid argon ionization chamber to gamma ray shower detection is discussed. Several variations are examined, and their merits and deficiencies pointed out. A design which looks promising uses sheets of foil and aluminized strips on mylar as the ion collectors, and detects the current as the output signal.

Polyfunctional monomers such as allyl methacrylate, adlyl acrylate, and diallyl maleate were found to greatly enhance the radiation crosslinking of many polymers. The radiation dose for incipient gelation of polyethylene is reduced by a factor of approximately 25; for polypropylene, the factor is 1500. Normally degradable polymers such as polyisobutylene and cellulose acetate were readily crosslinked at doses less than 1 Mirad. The ultimate scission/ crosslinking ratio for polyethylene and polypropylene is unchanged by the presence of monomer, and the swelling behavior of the gels follows the Flory-Rehner equation. Physical properties of the monomer-crosslinked polyethylene were markedly improved over the straight crosslinked polymer. High temperature properties of all polymers were improved. Polyvinyl alcohol film exhibits enhanced crosslinking when irradiated in the presence of methanol/water/allyl methacrylate mixtures. Incipient gelation occurs at 0.06 Mrad for a typical 99% hydrolyzed polyvinyl alcohol. 6,6 Nylon was crosslinked employing doses of 1--3 Mrads. A mechanism is discussed for the enhancement of polymer crosslinking via polyfunctional monomers. (auth)