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The Automated Variance Reduction Generator (ADVANTG) software is developed, maintained, and distributed by ORNL to extend the capabilities of the Los Alamos National Laboratory MCNP® code in continuous-energy Monte Carlo simulations of radiation shielding and related applications. ADVANTG automates the process of generating space- and energy-dependent variance reduction parameters that enable MCNP® simulations to obtain uniformly converged tallies over arbitrary regions of interest, including the whole problem domain. Weight-window bounds and biased source distributions are efficiently generated based on three-dimensional (3D) discrete ordinates solutions of the adjoint transport equation using the parallel SCALE Denovo solver. Recent applications of ADVANTG include the estimation of LWR pressure vessel fluence (illustrated below), full-field dose-rate distributions throughout the International Thermonuclear Experimental Reactor (ITER) fusion tokamak facility, high-resolution space- and energy-dependent neutron flux distributions for activation analyses of LWR containment structures for decommissioning planning, and irradiation experiments isotope production and fusion materials research at ORNL’s High Flux Isotope Reactor (HFIR).

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Licensing: ADVANTG 3.0.3 is available from RSICC and NEA as C00831.