Some embodiments include a low-dose CT apparatus. Such an apparatus can comprise a plurality of x-ray sources disposed on a gantry and spaced apart along a z-axis. The sources may be configured to produce substantially overlapping fan beams, wherein overlap is substantially complete at a detector surface. Some embodiments also include a controller in electronic communication with the plurality of x-ray sources. The controller may be adapted to switch the plurality of x-ray sources between on and off states such that only one x-ray source is in an on state at any time. Furthermore, the controller circuit may be in electronic communication with at least one x-ray detector and may be adapted to synchronize the x-ray detector with the plurality of x-ray sources such that detected x-rays can be matched to an x-ray source.