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Author Billen, James H. ♦ Takeda, Harunori ♦ Young, Lloyd M.
Source CiteSeerX
Content type Text
File Format PDF
Language English
Subject Domain (in DDC) Computer science, information & general works ♦ Data processing & computer science
Subject Keyword Conventional Ccl ♦ High-energy Radio-frequency Quadrupole ♦ Longitudinal Focusing ♦ Longitudinal Focusing Strength ♦ Different Transverse Focusing Lattice ♦ Coupling-cavity Orientation ♦ Higher-frequency Structure ♦ Constant Period ♦ Duty 28-ma Beam ♦ Ion Linac Design ♦ High Rfq Output Energy ♦ Drift-tube Linac ♦ Rfq Beam ♦ Separate Matching Section ♦ Cavity Change ♦ Low Accelerating Gradient ♦ Considerable Flexibility ♦ Smooth Transverse ♦ 1300-mhz Ccdtl ♦ Coupled-cavity Drift-tube Linac ♦ 700-mhz Ccdtl ♦ Cw 135-ma Beam ♦ 80-ma Beam ♦ Large Negative Synchronous Phase ♦ 433-mhz 10-mev Rfq ♦ Drift Tube ♦ Beam-dynamics Simulation ♦ 805-mhz Structure ♦ 8-mev Rfq ♦ 7-mev Rfq ♦ Following Structure ♦ High Energy ♦ Cw 100-ma Beam
Description We examine ion linac designs that start with a high-energy radio-frequency quadrupole (RFQ) followed by either a drift-tube linac (DTL) or a coupled-cavity drift-tube linac (CCDTL). For high energies, a conventional CCL follows the CCDTL. High RFQ output energy allows tailoring the transverse and longitudinal focusing strengths to match into the following structure. When the RFQ beam enters a higher-frequency structure, the DTL or CCDTL starts with a low accelerating gradient and large negative synchronous phase. The gradient and phase both ramp up gradually to higher values. Other changes later in the machine are also gradual. Beam-dynamics simulations show that these linacs require no separate matching sections. Applications include a cw 100-mA H+ beam from a 350-MHz, 6.7-MeV RFQ injecting a 700-MHz CCDTL and CCL; a 7 % duty 28-mA H- beam from a 402.5-MHz, RFQ and DTL injecting 805-MHz structures; a cw 135-mA D+ beam produced by a 175-MHz, 8-MeV RFQ and DTL; and a 2.4 % duty, 80-mA H+ beam using a 433-MHz 10-MeV RFQ and a 1300-MHz CCDTL. The machines take advantage of the considerable flexibility of the CCDTL. Designs can use a variety of different transverse focusing lattices. Use of two coupling-cavity orientations permits a constant period even when the number of drift tubes per cavity changes along the linac.
Educational Role Student ♦ Teacher
Age Range above 22 year
Educational Use Research
Education Level UG and PG ♦ Career/Technical Study
Learning Resource Type Article
Publisher Institution In High-Intensity Ion Linacs”, this conference