PROBLEM TO BE SOLVED: To acquire a plurality of pieces of energy information on a radiation ray irradiated based on a constant tube voltage, and accurately calculate the number of photons corresponding to each piece of energy information without being affected by the deterioration in measurement accuracy.SOLUTION: A radiographic apparatus includes a detection part for acquiring measurement information based on a result of detection of a radiation ray irradiated based on a constant tube voltage, a moment utilization part for acquiring second measurement information on the radiation ray based on a moment of the measurement information in which the radiation ray is detected a plurality of times, an energy determination part for determining a plurality of energies to approximate the energy distribution of the radiation ray, and a calculation part for calculating the number of photons corresponding to each of the plurality of energies based on the second measurement information.SELECTED DRAWING: Figure 1【課題】一定の管電圧に基づいて照射された放射線の複数のエネルギー情報を取得して、各々のエネルギー情報に対応する光子の数を、測定精度の低下の影響を受けることなく高精度に算出すること。【解決手段】放射線撮影装置は、一定の管電圧に基づいて照射された放射線の検出結果に基づく測定情報を取得する検出部と、放射線を複数回検出した測定情報の積率に基づいて、放射線の第二の測定情報を取得する積率利用部と、放射線のエネルギー分布を近似するための複数のエネルギーを決定するエネルギー決定部と、複数のエネルギーのそれぞれに対応した光子数を、第二の測定情報に基づいて算出する算出部と、を備える。【選択図】 図１
