The invention provides a method for accelerating protons and carbon ions up to 450 MeV/u in a very compact linac, the method comprising subjecting the particles to a radio frequency quadrupole field to accelerate the particles to at least 3 MeV/u, a drift tube linac (DTL) to an energy of 20 MeV/u, followed by a coupled DTL to 45 MeV/u and finally a high-gradient section made of CCL-type standing wave cavities or negative harmonic traveling wave cavities operating at S-band frequencies and capable of delivering voltage gradients of 40 to 60 MV/m. Focusing the accelerated particles while accelerated to higher energy is provided by appropriately placed constant field permanent magnets and electromagnetic quadrupoles. The compactness and power efficiency of the linac is enabled by using high-gradient structure in the S-band frequencies for lower energy particles than ever before. The low-intensity required for hadron therapy allows the use of small-aperture S-band structures and the operation at very high gradient compared to high-intensity machines for research. Operating with very short sub-microsecond pulses at repetition rates up to 400 Hz allows the fast and flexible beam energy and intensity tuning not provided by existing hadron therapy machines. The designed linac is capable of accelerating ions as heavy as neon to the full 450 MeV/u energy, therefore allowing fast beam switching if different ion sources are installed in the front-end of the linac.

An apparatus may include a drift tube assembly having a plurality of drift tubes to conduct an ion beam along a beam propagation direction. The plurality of drift tubes may define a multi-gap configuration corresponding to a plurality of acceleration gaps, wherein at least one powered drift tube of the drift tube assembly is coupled to receive an RF voltage signal. The apparatus may also include a DC electrode assembly that includes a conductor line, arranged within a resonator coil that is coupled to receive a DC voltage signal into the at least one powered drift tube. The DC electrode assembly may also include a DC electrode arrangement, connected to the conductor line and disposed within the at least one powered drift tube.

When accelerating first ions, radio frequency power is fed to a drift tube linear accelerator so that the phase difference between an accelerating half cycle for accelerating the first ions in one of the plurality of drift tube gaps and the accelerating half cycle for accelerating the accelerated first ions reaching the next drift tube gap is set to a first accelerating cycle phase difference; and when accelerating second ions having a charge-to-mass ratio lower than the first ions, the radio frequency power is fed to the drift tube linear accelerator so that the phase difference between an accelerating half cycle for accelerating the second ions in the one drift tube gap and the accelerating half cycle for the accelerated second ions reaching the next drift tube gap is set to a second accelerating cycle phase difference that is larger than the first accelerating cycle phase difference.

A hybrid linear accelerator is disclosed comprising a standing wave linear accelerator section (SW section) followed by a travelling wave linear accelerator section (TW section). In one example, RF power is provided to the TW section and power not used by the TW section is provided to the SW section via a waveguide. An RF switch, an RF phase adjuster, and/or an RF power adjuster is provided along the waveguide to change the energy and/or phase of the RF power provided to the SW section. In another example, RF power is provided to both the SW section and the TW section, and RF power not used by the TW section is provided to the SW section, via an RF switch, an RF phase adjuster, and/or an RF power. In another example, an RF load is matched to the output of the TW section by an RF switch.

When accelerating first ions, radio frequency power is fed to a drift tube linear accelerator so that the phase difference between an accelerating half cycle for accelerating the first ions in one of the plurality of drift tube gaps and the accelerating half cycle for accelerating the accelerated first ions reaching the next drift tube gap is set to a first accelerating cycle phase difference; and when accelerating second ions having a charge-to-mass ratio lower than the first ions, the radio frequency power is fed to the drift tube linear accelerator so that the phase difference between an accelerating half cycle for accelerating the second ions in the one drift tube gap and the accelerating half cycle for the accelerated second ions reaching the next drift tube gap is set to a second accelerating cycle phase difference that is larger than the first accelerating cycle phase difference.

A diaphragm flange for connecting the tubes in a particle accelerator while minimizing beamline impedance. The diaphragm flange includes an outer flange and a thin diaphragm integral with the outer flange. Bolt holes in the outer flange provide a means for bolting the diaphragm flange to an adjacent flange or beam tube having a mating bolt-hole pattern. The diaphragm flange includes a first surface for connection to the tube of a particle accelerator beamline and a second surface for connection to a CF flange. The second surface includes a recessed surface therein and a knife-edge on the recessed surface. The diaphragm includes a thickness that enables flexing of the integral diaphragm during assembly of beamline components. The knife-edge enables compression of a soft metal gasket to provide a leak-tight seal.

A linear proton accelerator includes a plurality of accelerator components arranged after one another, and a proton source and a plurality of accelerating units. The accelerator further includes a reticular support structure for supporting the accelerator components. The support structure is shaped as a prism with a polygonal cross-section, and has a plurality of side faces joining opposite ends of the prism. The support structure is arranged concentrically with respect to the accelerator components.

Embodiments herein are directed to a linear accelerator assembly for an ion implanter. In some embodiments, a LINAC may include a coil resonator and a plurality of drift tubes coupled to the coil resonator by a set of flexible leads.

An apparatus may include a drift tube assembly, comprising a plurality of drift tubes to conduct an ion beam along a beam propagation direction. The plurality of drift tubes may define a multi-gap configuration corresponding to a plurality of acceleration gaps, wherein the plurality of drift tubes further define a plurality of RF quadrupoles, respectively. As such, the plurality of quadrupoles are arranged to defocus the ion beam along a first direction at the plurality of acceleration gaps, respectively, where the first direction extends perpendicularly to the beam propagation direction.

A linear accelerator apparatus may include a beamline enclosure that defines a polygonal backbone, and a plurality of acceleration stages, disposed along a length of the beamline enclosure. A given acceleration stage may include a drift tube assembly to conduct an ion beam therethrough, a resonator, coupled to deliver an RF signal to the drift tube assembly, and a quadrupole assembly to shape the ion beam. As such, at a first acceleration stage, a first resonator may be disposed along a first side of the polygonal backbone, and at a second acceleration stage, adjacent to and downstream of the first acceleration stage, a second resonator may be disposed along a second side of the polygonal backbone, different from the first side.