Alpha interactions with neutrals in the ablation cloud of a refueling pellet are considered as a fast alpha diagnostic through charge‐capture radiation (ACCR) by the alphas or their complete neutralization and escape. Calculations of pellet penetration into a reactor plasma indicate that regions ofr/a>0.61 could be reached by refueling pellets with initial radii of 4 mm, hence this would be an outer core diagnostic. A spherically symmetric neutral‐gas shielding model (SSMNGSM) in which ionization is treated self‐consistently and governed by local thermodynamic equilibrium is used in these calculations. Collisional processes are found to govern the alpha–cloud interactions and local equilibrium calculations were performed in which the charge exchange and ionization cross sections are used to obtain the state fractions of the alphas in the cloud. At 1640 A˚ the ratio of ACCR to cloud bremsstrahlung is found to be 10−5whereas at 304 A˚ this ratio ranges from 3×10−3to 0.5 for the cases considered; no neutralized alphas escape the cloud. Magnetic field effects are considered and they appear to reduce the bremsstrahlung from the cloud by a factor of 300 at 304 A˚ in regions perpendicular to the magnetic field from the pellet’s surface; escape of neutralized alphas may be possible in these directions. Alpha refueling pellet interactions are potentially useful as outer core fast alpha diagnostics and this could be tested in near term experiments.