A charge stripping film for a charge stripping device of ion beam is a carbon film produced by annealing a polymer film, and has a film thickness of 10 m to 150 m, an area of at least 4 cm.sup.2, and an atomic concentration of carbon of at least 97%. A charge stripping film for a charge stripping device of ion beam is a carbon film having a thermal conductivity in a film surface direction at 25 C. of at least 300 W/mK, and has a film thickness of 10 m to 150 m, an area of at least 4 cm.sup.2, and an atomic concentration of carbon of at least 97%.

The present disclosure relates to compact isochronous sector-focused cyclotrons having reduced dimensions and weight compared with state of the art cyclotrons of same energies. In one implementation, a cyclotron may include two pole magnets facing each other in a chamber defined by a yoke having base plates and flux return yokes forming a lateral wall of the chamber. The magnet poles may include between three and eight hill sectors alternating with a same number of valley sectors distributed about a central axis. The lip of the abyssal opening may be positioned at a distance from the corresponding valley peripheral edge. The flux return yoke may have a thickness in the portions facing valley sectors, such that the ratio of the product of the distance times the thickness to the square of the distance of the peripheral edge to the central axis is less than 5%.

A charge stripping film for an ion beam includes a single layer body of a graphitic film having a carbon component of at least 96 at % and a thermal conductivity in a film surface direction at 25 C. of at least 800 W/mK, or a laminated body of the graphitic film. The charge stripping film has a thickness of 100 nm to 10 m, a tensile strength in a film surface direction of at least 5 MPa, a coefficient of thermal expansion in the film surface direction of at least 110.sup.5/K, and an area of at least 4 cm.sup.2.

A charge stripping film for an ion beam includes a single layer body of a graphitic film having a carbon component of at least 96 at % and a thermal conductivity in a film surface direction at 25 C. of at least 800 W/mK, or a laminated body of the graphitic film. The charge stripping film has a thickness of 100 nm to 10 m, a tensile strength in a film surface direction of at least 5 MPa, a coefficient of thermal expansion in the film surface direction of at least 110.sup.5/K, and an area of at least 4 cm.sup.2.

Radio-frequency (RF) electrode for a cyclotron. The RF electrode includes a hollowed dee having first and second surfaces that oppose each other and define a gap therebetween. The hollowed dee is configured to be electrically controlled to direct a beam of charged particles through the gap and along an orbit plane of the cyclotron. The orbit plane extends parallel to the first and second surfaces through the gap. The RF electrode also includes a bridge structure that is coupled to and extends away from the hollowed dee. The bridge structure includes a side wall that defines an interior cavity of the bridge structure. The side wall has a particle opening therethrough that coincides with or is proximate to the orbit plane such that the particle opening receives neutral particles from an orbit of the charged particles.

Radio-frequency (RF) electrode for a cyclotron. The RF electrode includes a hollowed dee having first and second surfaces that oppose each other and define a gap therebetween. The hollowed dee is configured to be electrically controlled to direct a beam of charged particles through the gap and along an orbit plane of the cyclotron. The orbit plane extends parallel to the first and second surfaces through the gap. The RF electrode also includes a bridge structure that is coupled to and extends away from the hollowed dee. The bridge structure includes a side wall that defines an interior cavity of the bridge structure. The side wall has a particle opening therethrough that coincides with or is proximate to the orbit plane such that the particle opening receives neutral particles from an orbit of the charged particles.

The present disclosure relates to compact isochronous sector-focused cyclotrons having reduced dimensions and weight compared with state of the art cyclotrons of same energies. In one implementation, a cyclotron may include two pole magnets facing each other in a chamber defined by a yoke having base plates and flux return yokes forming a lateral wall of the chamber. The magnet poles may include between three and eight hill sectors alternating with a same number of valley sectors distributed about a central axis. The lip of the abyssal opening may be positioned at a distance from the corresponding valley peripheral edge. The flux return yoke may have a thickness in the portions facing valley sectors, such that the ratio of the product of the distance times the thickness to the square of the distance of the peripheral edge to the central axis is less than 5%.

The present disclosure relates to a magnet pole for an isochronous sector-focused cyclotron having hill and valley sectors alternatively distributed around a central axis, Z, each hill sector having an upper surface bounded by four edges: an upper peripheral edge, an upper central edge, a first and a second upper lateral edges, and a peripheral surface extending from the upper peripheral edge to a lower peripheral line. The upper peripheral edge of at least one hill sector may further include a concave portion with respect to the central axis defining a recess extending at least partially over a portion of the peripheral surface of the corresponding hill sector.

The present disclosure relates to a magnet pole for an isochronous sector-focused cyclotron having hill and valley sectors alternatively distributed around a central axis, Z, each hill sector having an upper surface bounded by four edges: an upper peripheral edge, an upper central edge, a first and a second upper lateral edges, and a peripheral surface extending from the upper peripheral edge to a lower peripheral line. The upper peripheral edge of at least one hill sector may further include a concave portion with respect to the central axis defining a recess extending at least partially over a portion of the peripheral surface of the corresponding hill sector.

The present disclosure relates to a magnet pole for an isochronous sector-focused cyclotron having hill and valley sectors alternatively distributed around a central axis, Z, each hill sector having an upper surface bounded by four edges: an upper peripheral edge, an upper central edge, a first and a second upper lateral edges. The upper surface of at least one hill sector may further include: a recess extending over a length between a proximal end and a distal end along a longitudinal axis intersecting the upper peripheral edge and the upper central edge. The recess may be separate from the first and second upper lateral edges over at least 80% of its length, and a pole insert having a geometry fitting in the recess may be positioned in, and reversibly coupled to the recess.