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Neutronics Roster

Every fuel, isotope, and byproduct in the reactor's transmutation economy. Fuels, fertile feedstock, and the two usable isotopes are obtainable; the rest of the produced byproducts leave only as Nuclear Waste.

Fissile fuels

What sustains the chain reaction — load these into the Fuel Port.

ItemIdRole · how you get it
Uranium-235reactor.fuel.uranium235Fissile — Uranium-235, the workhorse fuel. Enrich Raw Uranium Ore at an Enrichment Centrifuge.
Plutonium-239reactor.fuel.plutonium239Fissile — Plutonium-239, premium (1.5× yield) & twitchy (low β). Bred from U-238 in a breeder.
Uranium-233reactor.fuel.uranium233Fissile — Uranium-233. Reserved: no thorium feedstock item yet, so not currently breedable.

Fertile feedstock

Not fissile on its own; breeds to a fissile fuel under neutron flux.

ItemIdRole · how you get it
Uranium-238reactor.fuel.uranium238Fertile — Uranium-238. Comes off enrichment as tailings + from burnt-out rods; breeds to Pu-239.

Usable byproduct isotopes

Produced deep in the over-breed actinide walk and withdrawn as themselves for their dedicated uses.

ItemIdRole · how you get it
Americium-241reactor.isotope.americium_241Usable byproduct — produced deep in the over-breed walk; withdraws as ITSELF (not consolidated to waste).
Plutonium-238reactor.isotope.plutonium_238Usable byproduct — produced deep in the over-breed walk; withdraws as ITSELF (not consolidated to waste).

The waste sink

ItemIdRole · how you get it
Nuclear Wastereactor.item.nuclear_wasteWaste sink — what every non-usable withdrawn byproduct consolidates into.

Produced byproducts — withdraw as Nuclear Waste

The reactor genuinely produces each of these as it runs, but the Fuel Port consolidates them into the single Nuclear Waste item on withdrawal, so you never collect them individually.

ItemIdRole · how you get it
Cesium-137reactor.isotope.cesium_137Produced → Nuclear Waste — the reactor makes it, but it withdraws as Nuclear Waste, so it is unobtainable as its own item.
Strontium-90reactor.isotope.strontium_90Produced → Nuclear Waste — the reactor makes it, but it withdraws as Nuclear Waste, so it is unobtainable as its own item.
Technetium-99reactor.isotope.technetium_99Produced → Nuclear Waste — the reactor makes it, but it withdraws as Nuclear Waste, so it is unobtainable as its own item.
Iodine-131reactor.isotope.iodine_131Produced → Nuclear Waste — the reactor makes it, but it withdraws as Nuclear Waste, so it is unobtainable as its own item.
Molybdenum-99reactor.isotope.molybdenum_99Produced → Nuclear Waste — the reactor makes it, but it withdraws as Nuclear Waste, so it is unobtainable as its own item.
Xenon-135reactor.isotope.xenon_135Produced → Nuclear Waste — the reactor makes it, but it withdraws as Nuclear Waste, so it is unobtainable as its own item.
Plutonium-240reactor.isotope.plutonium_240Produced → Nuclear Waste — the reactor makes it, but it withdraws as Nuclear Waste, so it is unobtainable as its own item.
Plutonium-241reactor.isotope.plutonium_241Produced → Nuclear Waste — the reactor makes it, but it withdraws as Nuclear Waste, so it is unobtainable as its own item.
Curium-244reactor.isotope.curium_244Produced → Nuclear Waste — the reactor makes it, but it withdraws as Nuclear Waste, so it is unobtainable as its own item.
Iodine-135reactor.isotope.iodine_135Produced → Nuclear Waste — the reactor makes it, but it withdraws as Nuclear Waste, so it is unobtainable as its own item.
Neptunium-239reactor.isotope.neptunium_239Produced → Nuclear Waste — the reactor makes it, but it withdraws as Nuclear Waste, so it is unobtainable as its own item.