A superconductive electromagnet according to an embodiment includes a pair of main coils that have an annular shape, a pair of magnetic poles that are arranged on an inner peripheral side of the main coils, and that respectively have opposing surfaces which are planes opposing each other while being separated from each other in an axial direction of the main coils, and a pair of correction coils that are arranged between a pair of the magnetic poles. In this manner, density of a magnetic flux generated by the main coils is corrected by density of a magnetic flux generated by the correction coils. Accordingly, it is possible to realize improved uniformity in the density of the magnetic flux in a beam duct inside a deflection electromagnet.
