IPAC2018 - List of Authors (Shumail, M.)

Paper	Title	Page
THPML125	Efficiency Analysis of High Average Power Linacs for Environmental and Industrial Applications	4970
	M. Shumail, V.A. Dolgashev SLAC, Menlo Park, California, USA
	Funding: U.S. Department of Energy, HEP under Research Opportunities in Accelerator Stewardship: LAB 16-1438. We present comprehensive efficiency equations and useful scaling laws to optimally determine design parameters for high efficiency rf linacs. For the first time we have incorporated the parasitic losses due to the higher order cavity modes into the efficiency analysis of the standing wave (SW) and travelling wave (TW) accelerators. We have also derived the efficiency equations for a new kind of attenuation-independent-impedance travelling wave (ATW) accelerators where the shunt impedance can be optimized independent of the group velocity. We have obtained scaling laws which relate the rf to beam efficiency to the linac length, beam aperture radius , phase advance per cell, and the type of accelerating structure: SW versus TW, disk-loaded (DL) versus nose-cone (NC). We give an example of using these scaling laws to determine a feasible set of parameters for a 10 MeV, 10 MW linac with 97.2% efficiency.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML125
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THPML126	Design of High Efficiency High Power CW Linacs for Environmental and Industrial Applications	4974
	M. Shumail, V.A. Dolgashev, C.M. Markusen SLAC, Menlo Park, California, USA
	Funding: US Department of Energy, Office of High Energy Physics, through Accelerator Stewardship Grant We have used our accelerator design toolbox equations to design three high efficiency and high power CW accelerators for the environmental and medical applications. These are: 2MeV-1MW, 10MeV-10MW, and 10MeV-1MW linacs. These are all 10 m long, 1.3 GHz, π-mode standing wave structures with design efficiencies of 96.8, 97.4 and 86.5 %, and optimal coupling coefficients of 32.9, 43.5, and 7.45, respectively. We present the detailed design parameters of these linacs. The study of single-bunch beam breakup for these linacs and the simulations results from ABCI are also included. The initial cavities are optimized according to the speed of the electron bunch to maximize the shunt impedance. The plots of peak surface fields on these cavities are also presented. We have also included a detailed thermal analysis of these linacs. Finally, we present the results of ASTRA simulations of the three linacs with magnetic focusing. We have also included the complete design of rf-distributed-coupling manifold for the third linac along with the HFSS® simulation results.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML126
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Efficiency Analysis of High Average Power Linacs for Environmental and Industrial Applications

4970

M. Shumail, V.A. Dolgashev
SLAC, Menlo Park, California, USA

Funding: U.S. Department of Energy, HEP under Research Opportunities in Accelerator Stewardship: LAB 16-1438.
We present comprehensive efficiency equations and useful scaling laws to optimally determine design parameters for high efficiency rf linacs. For the first time we have incorporated the parasitic losses due to the higher order cavity modes into the efficiency analysis of the standing wave (SW) and travelling wave (TW) accelerators. We have also derived the efficiency equations for a new kind of attenuation-independent-impedance travelling wave (ATW) accelerators where the shunt impedance can be optimized independent of the group velocity. We have obtained scaling laws which relate the rf to beam efficiency to the linac length, beam aperture radius , phase advance per cell, and the type of accelerating structure: SW versus TW, disk-loaded (DL) versus nose-cone (NC). We give an example of using these scaling laws to determine a feasible set of parameters for a 10 MeV, 10 MW linac with 97.2% efficiency.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML125

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPML126

Design of High Efficiency High Power CW Linacs for Environmental and Industrial Applications

4974

M. Shumail, V.A. Dolgashev, C.M. Markusen
SLAC, Menlo Park, California, USA

Funding: US Department of Energy, Office of High Energy Physics, through Accelerator Stewardship Grant
We have used our accelerator design toolbox equations to design three high efficiency and high power CW accelerators for the environmental and medical applications. These are: 2MeV-1MW, 10MeV-10MW, and 10MeV-1MW linacs. These are all 10 m long, 1.3 GHz, π-mode standing wave structures with design efficiencies of 96.8, 97.4 and 86.5 %, and optimal coupling coefficients of 32.9, 43.5, and 7.45, respectively. We present the detailed design parameters of these linacs. The study of single-bunch beam breakup for these linacs and the simulations results from ABCI are also included. The initial cavities are optimized according to the speed of the electron bunch to maximize the shunt impedance. The plots of peak surface fields on these cavities are also presented. We have also included a detailed thermal analysis of these linacs. Finally, we present the results of ASTRA simulations of the three linacs with magnetic focusing. We have also included the complete design of rf-distributed-coupling manifold for the third linac along with the HFSS® simulation results.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML126

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)