Page 8 - Demo

additive in power (or photon numbers) by simply increasing the number of fibers. Because of the fiber based technology, it is highly efficient and can operate either nearly cw-fashion or tunable fiber-by-fiber (if necessary).
In addition to the above laser monitoring of chemical elements, the real-time isotopic concentration of the TRUs and FPs is conducted using gamma-spectroscopy [36]. We will rely on two sources of gamma: (1) internally generated during fission – passive spectroscopy, (2) externally generated gamma beam relying on Nuclear Fluorescence Resonance – active spectroscopy. The laser Compton gamma-ray detectors [37], [38], and [39] are utilized. Externally generated gamma-rays can be energy-selective and mono-energetic. This feature allows the specific identification of the nuclear transitions. These gamma sources and detectors can go in parallel to the above laser sources and detectors. Knowledge of the isotopic concentration is paramount, since keff is strongly affected by the presence of not just various actinides but their specific isotopes as well, e.g., Cm-243 rises keff significantly, whereas Cm-244 might actually lower keff.
Due to the fusion-neutron based transmutator compact size, the transmutator can be co- located with a nuclear power plant, and become central component for waste disposal during the power plant’s lifetime as well as critical component during the decommissioning.
III. Neutron sources
In this section we will describe various neutron sources. To be a good candidate, the
neutron source must satisfy these requirements: (1) high energy, preferably to deliver 14 MeV D- T fusion neutrons. (2) high rate of neutrons 10-100 MW or 200 kW-2MW assuming keff=0.98 (3) robust, predictable and controllable, (4) pulsed (kHz) or steady-state, (5), all TRU must be within a few 14 MeV neutron fission mean free paths away from the neutron source.