ANL, Argonne, Illinois, USA
RadiaBeam, Santa Monica, California, USA
Argonne National Laboratory is developing an Advanced Compact Carbon Ion Linac (ACCIL) in collaboration with RadiaBeam Technologies. The 45-meter long linac is designed to deliver up to 109 carbon ions per second with variable energy from 45 MeV/u to 450 MeV/u. To optimize the linac design in this energy range both backward traveling wave and coupled cell standing wave S-band structures were analyzed. To achieve the required accelerating gradients our design uses accelerating structures excited with short RF pulses (~500 ns flattop). The front-end accelerating structures such as the RFQ, DTL and Coupled Cell DTL are designed to operate at lower frequencies to maintain high shunt impedance. In parallel with our design effort ANL's RF test facility has been upgraded and used for the testing of an S-band high-gradient structure designed and built by Radiabeam for high pulsed RF power operation. The 5-cell S-band structure demonstrated 52 MV/m acceleration field at 2 μs 30 Hz RF pulses. A detailed physics design, including a comparison of different accelerating structures and end-to-end beam dynamics simulations of the ACCIL will be presented.
ANL, Argonne, Illinois, USA
A pulsed multi ion injector linac is being developed by ANL for Jefferson Laboratory's Electron Ion Collider (JLEIC). The linac is designed to deliver both polarized and non polarized ion beams to the booster synchrotron at energies ranging from 135 MeV for hydrogen to 43 MeV/u for lead ions. The linac is composed of a 5 MeV/u room temperature section and a superconducting section with variable velocity profile for different ion species. This paper presents the results of the RF design of the main components and the beam dynamics simulations of the linac front-end with the goal of achieving design specifications cost-effectively.
ANL, Argonne, USA
Northern Illinois University, DeKalb, Illinois, USA
The original design of the JLEIC pre-booster was a 3-GeV figure-8 shaped synchrotron with a circumference of about 240 m. In the current baseline design, the 3-GeV pre-booster was converted into an 8-GeV booster of the same shape and size but using super-ferric magnets with fields up to 3 Tesla. In order to limit the foot-print of the JLEIC ion complex and reduce its total cost, we have designed a more compact and cost-effective octagonal 3-GeV ring about half the size of the original one. At 3 GeV, the figure-8 shape is not required to preserve ion polarization; Siberian snakes with reasonable magnetic fields can be used for spin correction. As the ion collider ring requires an injection energy of at least 8 GeV, we propose to use the existing electron storage ring, which is part of the electron complex, as a large booster for the ions up to 11 GeV. The design optimization of the pre-booster ring will be presented leading to the final octagonal ring design. Preliminary beam simulations will also be presented and discussed.
ANL, Argonne, Illinois, USA
JLab, Newport News, Virginia, USA
The current baseline design for the JLab EIC (JLEIC) ion accelerator complex is based on a pulsed superconducting linac, an 8-GeV booster followed by a dual function 20-100 GeV booster and collider ring. Both the 8-GeV booster and collider ring will use super-ferric magnets with fields up to 3 Tesla. We here propose an alternative cost-effective and low-risk design where the 8-GeV booster is replaced with a more compact 3-GeV booster using room-temperature magnets. The electron storage ring, which is part of the electron complex, will also serve as large booster for the ions, up to 11 GeV. We also propose two stages for the JLEIC. A first low-energy stage up to 60 GeV, where room-temperature magnets (up to 1.6 Tesla) will be used for the ion collider ring, to be later replaced with 6 Tesla superconducting magnets in a second stage of the project providing up to 200 GeV energy. In this second stage, the 1.6 T room-temperature magnets will replace the PEP-II magnets in the electron storage ring to boost the ions to higher energies (25 GeV or higher) for appropriate injection into the higher energy collider. Details and feasibility of the proposed plan will be presented and discussed.
ANL, Argonne, Illinois, USA
Fermilab, Batavia, Illinois, USA
Argonne National Laboratory is developing a super-conducting resonator cryomodule for the acceleration of 2 mA H− beams from 2.1 to 10.3 MeV for Fermi National Accelerator Laboratory's Proton Improvement Plan II. The cryomodule contains 8 superconducting half-wave resonators operating at 162.500 MHz with a 120 kHz tuning window. This paper reviews the half-wave resonator fabrication techniques used to manipulate the resonant frequency to the design goal of 162.500 MHz at 2.0 K. This also determines the target frequency at select stages of resonator construction, which will be discussed and supported by measurements.
This research used resources of ANL's ATLAS facility, which is a DOE Office of Science User Facility.
FRIB, East Lansing, USA
INFN/LNL, Legnaro (PD), Italy
KEK, Ibaraki, Japan
ANL, Argonne, Illinois, USA
TRIUMF, Vancouver, Canada
JLab, Newport News, Virginia, USA
The Facility for Rare Isotope Beams' heavy ion con-tinuous-wave (CW) linac extends superconducting RF to low beam energy of 500 keV/u. 332 low-beta cavities are housed in 48 cryomodules. Technical development of high performance subsystems including resonator, cou-pler, tuner, mechanical damper, solenoid and magnetic shielding is necessary. In 2015, the first innovatively designed FRIB bottom-up prototype cryomodule was tested meeting all FRIB specifications. In 2016, the first full production cryomodule is constructed and tested. The preproduction and production cryomodule procurements and in-house assembly are progressing according to the project plan.