Abstract: The disclosure relates to systems and methods for accurate generation of material maps of volume of interests, for example, that include implants, for proton radiation therapy. In one implementation, the method may include determining most probable energy (MPE) using particle energy determined from particle counting data. The method may include generating a plurality of simulations that simulate interactions using different combination of properties for the volume of interest determined from representation data and/or from a database to determine most probable energy (MPE) for each simulation. The method may include comparing the MPE determined using the particle counting data to the MPE determined from each simulation. The method may further include selecting one simulation of the plurality of simulations based on the comparing. The method may also include generating a material map for the volume of interest using the one or more properties corresponding to the one simulation.