A cyclotron for accelerating charged particles comprising: • At least a first superconducting main coil and second superconducting main coil centred on a common central axis (z), arranged parallel to one another on either side of a median plane, normal to the central axis (z), and defining a symmetry plane of the cyclotron, said at least first and second superconducting main coils (11, 12) configured to generate a main magnetic field, when activated by a source of electric power, • A first field shaping unit and second field shaping unit arranged within the first and second superconducting main coils (11, 12) on either side of the median plane, and separated from one another by an acceleration gap, said first and second field shaping units (41, 42) being suitable for controlling in the acceleration gap a z-component (Bz) of the main magnetic field, which is parallel to the central axis (z), • At least a first field bump module and second field bump module arranged on either side of the median plane, and extending circumferentially over a common azimuthal angle (φb), for creating, when activated, a local magnetic field bump in the z-component (Bz) of the main magnetic field, wherein each of the field bump modules (51, 52) comprises; ∘ At least one superconducting bump coil (51b, 52b) configured to locally generate a broad magnetic field bump or dip when activated by a source of electric power, said magnetic field bump having a bell-shape of maximum bump magnitude (ΔBz), and being defined by a first gradient ((dBz / dr) 1) of the z-component (Bz) in a radial direction (r), Characterized in that, each of the field bump modules (51, 52) further comprises ∘ At least one superconducting bump shaping unit (51s, 52s) positioned such as to locally steepen the first gradient ((dBz / dr)1), produced by the at least one superconducting bump coil (51b, 52b), when said at least one superconducting bump shaping unit (51s, 52s) is activated. • At least a first superconducting main coil and second superconducting main coil centred on a common central axis (z), arranged parallel to one another on either side of a median plane, normal to the central axis (z), and defining a symmetry plane of the cyclotron, said at least first and second superconducting main coils (11, 12) configured to generate a main magnetic field, when activated by a source of electric power, • A first field shaping unit and second field shaping unit arranged within the first and second superconducting main coils (11, 12) on either side of the median plane, and separated from one another by an acceleration gap, said first and second field shaping units (41, 42) being suitable for controlling in the acceleration gap a z-component (Bz) of the main magnetic field, which is parallel to the central axis (z), • At least a first field bump module and second field bump module arranged on either side of the median plane, and extending circumferentially over a common azimuthal angle (φb), for creating, when activated, a local magnetic field bump in the z-component (Bz) of the main magnetic field, wherein each of the field bump modules (51, 52) comprises; ∘ At least one superconducting bump coil (51b, 52b) configured to locally generate a broad magnetic field bump or dip when activated by a source of electric power, said magnetic field bump having a bell-shape of maximum bump magnitude (ΔBz), and being defined by a first gradient ((dBz / dr) 1) of the z-component (Bz) in a radial direction (r), Characterized in that, each of the field bump modules (51, 52) further comprises ∘ At least one superconducting bump shaping unit (51s, 52s) positioned such as to locally steepen the first gradient ((dBz / dr)1), produced by the at least one superconducting bump coil (51b, 52b), when said at least one superconducting bump shaping unit (51s, 52s) is activated. ∘ At least one superconducting bump coil (51b, 52b) configured to locally generate a broad magnetic field bump or dip when activated by a source of electric power, said magnetic field bump having a bell-shape of maximum bump magnitude (ΔBz), and being defined by a first gradient ((dBz / dr) 1) of the z-component (Bz) in a radial direction (r), Characterized in that, each of the field bump modules (51, 52) further comprises ∘ At least one superconducting bump shaping unit (51s, 52s) positioned such as to locally steepen the first gradient ((dBz / dr)1), produced by the at least one superconducting bump coil (51b, 52b), when said at least one superconducting bump shaping unit (51s, 52s) is activated.