Progress In Electromagnetics Research M
ISSN: 1937-8726
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By A. Semychayevskyy

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This article describes numerical solutions for the electromagnetic interactions, known as `wakefields', of a proton beam with an RF cavity and a beampipe. Using FDTD calculations, time-varying electromagnetic solutions are obtained. Unlike modal expansion methods, FDTD allows to compute transient wakefields due to proton beam passing through the structures. A popular time-frequency analysis approach, the short-time Fourier transform (STFT), is applied to the electromagnetic fields inside a resonant cavity and past an open-ended beampipe. STFT enables a more explicit interpretation of the transitions between the fields radiated by moving charges and the resonant modes. The described time-frequency analysis is useful to engineers and accelerator physicists who analyze proton beam dynamics. As an extension of electromagnetic simulations using an extended proton bunch, a numerical Green's function approach is proposed in order to account for the wakefields due to individual superparticles.

A. Semychayevskyy, "Time-Frequency Analysis of Particle Beam Interactions with Resonant and Guiding Structures," Progress In Electromagnetics Research M, Vol. 73, 197-203, 2018.

1. Macridin, A., P. Spentzouris, and J. Amundson, "Impedances and wake functions for non- ultrarelativistic beams in circular chambers,", 1-14, FERMILAB-PUB-12-518-CD.

2. Chao, A. W., Physics of Collective Beam Instabilities in High Energy Accelerators, 384, Wiley, N.Y., 1993.

3. Weiland, T. and B. Zotter, "Wake potentials of a relativistic current in a cavity," Particle Accelerators, Vol. 11, No. 1, 143-151, 1981.

4. Tsakanian, A., E. Gjonaj, H. De Gersem, and T. Weiland, "Broadband SIBC formulation for a low- dispersion nite volume method in the time domain," IEEE Transactions on Magnetics, Vol. 52, No. 3, 7201204, 2016.

5. Wang, H., R. B. Palmer, and J. Gallardo, "Short-range generated wake eld in a at pillbox cavity by a sub-relativistic beam bunch,", Particle Accelerator Conference (PAC2001), Chicago, IL, BNL-68563-01/10-REV, July 2001.

6. Carron, N. J., "Fields of particles and beam exiting a conductor," Progress In Electromagnetics Research, Vol. 28, 147-183, 2000.

7. Taflove, A. and S. Hagness, Computational Electrodynamics. The Finite-Difference Time Domain Method, 3rd Ed., Artech House, 2005.

8. Clemens, M. and T. Weiland, "Discrete electromagnetism with the nite integration technique," Progress In Electromagnetics Research, Vol. 32, No. 1, 65-81, 2001.

9. Yuferev, S. V. and N. Ida, Surface Impedance Boundary Conditions. A Comprehensive Approach, 410, CRC Press, 2001.

10. Moghaddar, A. and E. K. Walton, "Time-frequency analysis of scattering from waveguide cavities," IEEE Trans. on Antennas and Propagation, Vol. 41, No. 5, 677-680, 1993.

11. Griffiths, D. J., Introduction to Electrodynamics, 4th Ed., 599, Pearson, 2013.

12. Jacobsen, E. and R. Lyons, "The sliding DFT," Signal Processing Magazine, Vol. 20, No. 2, 74-80, 2003.

13. Hockney, R. W., Computer Simulation Using Particles, 540, CRC Press, 1988.

14. Marrocco, G. and F. Bardatti, "FDTD computation of microwave device impulse response," Electronics Letters, Vol. 35, No. 3, 223-224, 1999.

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