PROBLEM TO BE SOLVED: To obtain a reconfiguration image having high quality in comparison with the prior art.SOLUTION: An X-ray computer tomography apparatus includes an X-ray tube and an X-ray detector. The X-ray tube generates an X-ray. The X-ray detector includes: a first detection unit 301 which is constituted of a first scintillator having first fluorescence decay time and detects the X-ray； and second detection units 302 which are constituted of second scintillators having the fluorescence decay time shorter than the first fluorescence decay time and detect the X-ray. The second detection units are arranged at both ends of the first detection unit in a channel direction.SELECTED DRAWING: Figure 3【課題】従来に比して高画質な再構成画像を得る。【解決手段】Ｘ線コンピュータ断層撮影装置は、Ｘ線管と、Ｘ線検出器とを含む。Ｘ線管は、Ｘ線を発生する。Ｘ線検出器は、第１の蛍光減衰時間を有する第１のシンチレータから構成され、前記Ｘ線を検出する第１の検出部３０１と、前記第１の蛍光減衰時間よりも短い蛍光減衰時間を有する第２のシンチレータから構成され、前記Ｘ線を検出する第２の検出部３０２とを有し、チャンネル方向において前記第１の検出部の両端に前記第２の検出部が配置される。【選択図】図３
