REACTANT INJECTORS

	The reactant injectors prepare and feed precisely controlled streams 
of matter and antimatter into the core. The matter reactant injector (MRI) 
accepts supercold deuterium from the primary deuterium tankage (PDT) in 
the upper bulge of the Engineering Hull and partially preburns it in a 
continuous gas-fusion process. It then drives the resulting gases through a 
series of throttleable nozzles into the upper magnetic constriction segment. 
The MRI consists of a conical structural vessel 5.2 x 6.3 meters, constructed 
of dispersion-strengthened woznium carbmolybdenide. Twenty-five shock 
attenuation cylinders connect it to the PDT and the major spacecraft framing 
members on Deck 30, maintaining 98% thermal isolation from the remainder 
of the Battle Section. In effect, the entire WPS ÒfloatsÓ within the hull in 
order to withstand 3x theoretical operational stresses.
	Within the MRI are six redundant cross-fed sets of injectors, each 
injector consisting of twin deuterium inlet manifolds, fuel conditioners, fusion 
preburner, magnetic quench block, transfer duct/gas combiner, nozzle head, 
and related control hardware. Slush deuterium enters the inlet manifolds at 
controlled flow rates and passes to the conditioners, where heat is removed 
to bring the slush to just above the solid transition point. Micropellets are 
formed, preburned by magnetic pinch fusion, and sent down into the gas 
combiner, where the ionized gas products are now at 10¤K. The nozzle heads 
then focus, align, and propel the gas streams into the constriction segments. 
Should any of the nozzles fail, the combiner would continue to supply the 
remaining nozzles, which would dilate to accommodate the increased 
supply. Each nozzle measures 102 x 175 cm and is constructed of frumium-
copper-yttrium 2343.
	At the opposite end of the M/ARA lies the antimatter reactant injector 
(ARI). The internal design and operation of the ARI is distinctly different from 
that of the MRI, owing to the hazardous nature of the antimatter fuel. Every 
step in manipulating and injecting antihydrogen must be undertaken with 
magnetic fields to isolate the fuel from the spacecraft structure. In some 
respects the ARI is a simpler device, requiring fewer moving components. 
However, the dangers inherent in handling antimatter necessitate 
uncompromising reliability in the mechanism. The ARI employs the same 
basic structural housing and shock attenuation struts as the MRI, with 
adaptations for magnetic-suspension fuel tunnels. The housing contains 
three pulsed antimatter gas flow separators, which break up the incoming 
antihydrogen into small manageable packets to boost up into the lower 
constriction segments. Each flow separator leads into an injector nozzle, and 
each nozzle cycles open in response to computer control signals. Nozzle 
firing can follow complex sequences, resulting from equally complex 
equations governing reaction pressures, temperatures, and desired power 
output.  Æ