近期研究兴趣为高亮度电子束的传输动力学与加速器系统中的尾场/阻抗的计算，特别是束流集体不稳定性、电子相干辐射机制研究，与中低能束流空间电荷效应等问题。研究方法倾向于根据相应的物理模型建立解析或半解析理论，利用全数值方法如粒子追踪模拟 (particle tracking) 或粒子网格模拟 (particle in cell) 等比较并验证理论的正确性。

目前感兴趣的课题包含，但不限于，高亮度 (高电流、低能散、低发散度) 电子在直线 (linac) 或能量循环/回收型 (recirculation/energy-recovery-linac, ERL)，及衍射极限储存环 (diffraction limited storage ring)、稳态微聚束储存环 (steady state microbunching, SSMB) 等加速器系统中的 (集体) 动力学，超快电子衍射/显微 (ultrafast electron diffraction/microscope, UED/M) 成像装置中的电子动力学问题，与自由电子激光理论 (free electron laser, FEL) 理论等。

对加速器动力学相关课题感兴趣的同学，中高年级本科生或即将就读硕、博研究生的同学，欢迎联系。每年招收硕士研究生1~2名，博士研究生1~2名，欢迎邮件联系。邮件标题或内容请提及感兴趣的关键字，谢绝罐头文。

以下为节选工作，完整列表见 

http://faculty.hust.edu.cn/jcytsai/zh_CN/lwcg/2191794/list/index.htm。更多介绍见 https://jcytsai.github.io/HBEB.github.io/HBEB/。

微束团不稳定(Microbunching instability, MBI)、相干同步辐射(coherent synchrotron radiation, CSR)

[1] C.-Y. Tsai, D. Douglas, R. Li, and C. Tennant, Linear Microbunching Analysis for Recirculation Machines, Phys. Rev. Accel. Beams 19, 114401 (2016). https://journals.aps.org/prab/abstract/10.1103/PhysRevAccelBeams.19.114401

[2] C.-Y. Tsai, S. Di Mitri, D. Douglas, R. Li, and C. Tennant, Conditions for coherent-synchrotron-radiation-induced microbunching suppression in multi-bend beam transport or recirculation arcs, Phys. Rev. Accel. Beams 20, 024401 (2017). https://journals.aps.org/prab/abstract/10.1103/PhysRevAccelBeams.20.024401

[3] C.-Y. Tsai, Ya. Derbenev, D. Douglas, R. Li, and C. Tennant, Vlasov analysis of microbunching instability for magnetized beams, Phys. Rev. Accel. Beams 20, 054401 (2017). https://journals.aps.org/prab/abstract/10.1103/PhysRevAccelBeams.20.054401

[4] C.-Y. Tsai, Concatenated analysis of phase space microbunching in high brightness electron beam transport, Nucl. Instru. Methods A 940, 462-474 (2019). https://www.sciencedirect.com/science/article/pii/S0168900219309064

[5] C.-Y. Tsai, An alternative view of coherent synchrotron radiation induced microbunching development in multibend recirculation arcs, Nucl. Instru. Methods A 943, 162499 (2019). https://www.sciencedirect.com/science/article/pii/S0168900219310423

[6] C.-Y. Tsai, W. Qin, K. Fan, J. Wu, and G. Zhou, Theoretical formulation of phase space microbunching instability in the presence of intrabeam scattering for single-pass or recirculation accelerators, Phys. Rev. Accel. Beams 23, 124401 (2020). https://journals.aps.org/prab/abstract/10.1103/PhysRevAccelBeams.23.124401

[7] C.-Y. Tsai and W. Qin, Semi-analytical analysis of high-brightness microbunched beam dynamics with collective and intrabeam scattering effects, Phys. Plasmas 28, 013112 (2021). https://aip.scitation.org/doi/10.1063/5.0038246

[8] C. Zhang, Y. Jiao, and C.-Y. Tsai, Isochronous and CSR-immune triple-bend achromat with periodic stable optics, Phys. Rev. Accel. Beams 24, 060701 (2021). https://journals.aps.org/prab/abstract/10.1103/PhysRevAccelBeams.24.060701

[9] C. Zhang, Y. Jiao, W. Liu, and C.-Y. Tsai, Suppression of the coherent synchrotron radiation induced emittance growth in a double-bend achromat with bunch compression, submiited to PRAB (2023)

稳态微聚束 (Steady-state microbunching, SSMB)

[1] C.-Y. Tsai, A.W. Chao, Y. Jiao, H.-W. Luo, M. Ying, Q.H. Zhou, Coherent radiation induced longitudinal single-pass beam breakup instability of a steady-state microbunch train in an undulator, Phys. Rev. Accel. Beams 24, 114401 (2021). https://journals.aps.org/prab/abstract/10.1103/PhysRevAccelBeams.24.114401

[2] C.-Y. Tsai, Longitudinal single-bunch instabilities driven by coherent undulator radiation in the cavity modulator of a steady-state microbunching storage ring, Nucl. Instrum. Method Section A 1042, 167454 (2022). https://www.sciencedirect.com/science/article/pii/S016890022200746X?via%3Dihub

[3] C.-Y. Tsai, Theoretical formulation of multi-turn collective dynamics in a laser cavity modulator with comparison to Robinson and high-gain free-electron laser instability, Phys. Rev. Accel. Beams 25, 064401 (2022). https://journals.aps.org/prab/abstract/10.1103/PhysRevAccelBeams.25.064401

[4] X. J. Deng, Y. Zhang, Z. L. Pan, Z. Z. Li, J. H. Bian, C.-Y. Tsai, R. K. Li, A. W. Chao, W. H. Huang and C. X. Tang, Average and statistical properties of coherent radiation from steady-state microbunching, J. Synchrotron Rad. 30, 35–50 (2023). https://journals.iucr.org/s/issues/2023/01/00/ju5047/ju5047.pdf

超快电子衍射/显微 (Ultrafast electron diffraction/microscope, UED/M)

[1] C.-Y. Tsai, K. Fan, G. Feng, J. Wu, G. Zhou, and Y. H. Wu, Low-energy high-brightness electron beam dynamics based on slice beam matrix method, Nucl. Instru. Methods A 937, 1-20 (2019). https://www.sciencedirect.com/science/article/pii/S0168900219306679

[2] Y. Song, C.-Y. Tsai, K. Fan, Y. Xu, and J. Yang, Analytical model of the streaking process in a single split-ring resonator for sub-ps electron pulse, Nucl. Instru. Methods A 987, 164861 (2020). https://www.sciencedirect.com/science/article/pii/S0168900220312584

[3] Y. Song, C.-Y. Tsai, K. Fan, J. Yang, H. Qi, MeV electron bunch compression and timing jitter suppression using a THz-driven resonator, Nucl. Instru. Methods A 1047, 167774 (2023). https://www.sciencedirect.com/science/article/pii/S016890022201066X

自由电子激光 (Free-electron laser, FEL)

[1] C.-Y. Tsai, J. Wu, C. Yang, M. Yoon, and G. Zhou, Sideband instability analysis based on a one-dimensional high-gain free electron laser model, Phys. Rev. Accel. Beams 20, 120702 (2017). https://journals.aps.org/prab/abstract/10.1103/PhysRevAccelBeams.20.120702

[2] C.-Y. Tsai, J. Wu, C. Yang, M. Yoon, and G. Zhou, Single-pass high-gain free-electron laser with transverse diffraction in the post-saturation regime, Phys. Rev. Accel. Beams 21, 060702 (2018). https://journals.aps.org/prab/abstract/10.1103/PhysRevAccelBeams.21.060702

[3] C.-Y. Tsai, C. Emma, J. Wu, C. Yang, M. Yoon, and G. Zhou, Area preserving scheme for efficiency enhancement in a single-pass tapered FEL, Nucl. Instru. Methods A 913, 107-119 (2019). https://www.sciencedirect.com/science/article/pii/S0168900218313767

[4] X. Wang, C. Feng, T. Liu, Z. Zhang, C.-Y. Tsai, J. Wu, C. Yang and Z. Zhao, Angular Dispersion Enhanced Prebunch for Seeding Ultrashort and Coherent EUV and Soft X-Ray Free-Electron Laser in Storage Rings, Journal of Synchrotron Radiation 26, pp.1-8 (2019). https://scripts.iucr.org/cgi-bin/paper?S1600577519002674

[5] C. Yang, X. Wang, C.-Y. Tsai, G. Zhou, Z. Zhang, E. D. Krug, A. Li, H. Deng, D. He, and J. Wu, The seed energy fluctuation of hard X-ray self-seeding Free Electron Laser, AIP Advances 9, 035254 (2019). https://aip.scitation.org/doi/10.1063/1.5091018

[6] C. Yang, C.-Y. Tsai, G. Zhou, X. Wang, Y. Hong, E. D. Krug, A. Li, H. Deng, D. He, and J. Wu, The detuning effect of crystal monochromator in self-seeding and oscillator free electron laser, Optics Express 27, No. 9, 013229 (2019). https://www.osapublishing.org/oe/abstract.cfm?URI=oe-27-9-13229

[7] X. Wang, C. Feng, C.-Y. Tsai, L. Zeng, and Z. Zhao, Obliquely incident laser and electron beam interaction in an undulator, Phys. Rev. Accel. Beams 22, 070701 (2019). https://journals.aps.org/prab/abstract/10.1103/PhysRevAccelBeams.22.070701

[8] G. Zhou, F.-J. Decker, Y. Ding, Y. Jiao, A. Lutman, T.J. Maxwell, T. Raubenheimer, J. Wang, C.-Y. Tsai, J.Y. Wu, W. Wu, C. Yang, M. Yoon, and J. Wu, Attosecond coherence time characterization in hard x-ray free-electron laser, Scientific Report 10, 5961 (2020). https://www.nature.com/articles/s41598-020-60328-4

[9] G. Zhou, Y. Jiao, T. Raubenheimer, J. Wang, A. Holman, C.-Y. Tsai, J. Wu, W. Wu, C. Yang, M. Yoon, and J. Wu, Coherence time characterization for hard x-ray free-electron Lasers, Optics Express, Vol.8, No.8, 10928 (2020). https://www.osapublishing.org/oe/abstract.cfm?URI=oe-28-8-10928

[10] G. Zhou, Z. Qu, Y. Ma, W.J. Corbett, Y. Jiao, H. Li, W. Qin, T.O. Raubenheimer, C.-Y. Tsai, J. Wang, C. Yang and J. Wu, Two-stage reflective self-seeding scheme for high-repetition-rate X-ray free-electron lasers, Journal of Synchrotron Radiation 28, pp.1-8 (2021). https://scripts.iucr.org/cgi-bin/paper?S1600577520014824

[11] C.-Y. Tsai et al., Analytical study of higher harmonic bunching and matrix formalism in linear high-gain free-electron laser model, Nucl. Instrum. Method Section A 1048, 167974 (2022). https://www.sciencedirect.com/science/article/pii/S0168900222012669

粒子源 (particle sources)

[1] D. Abbott et al., Production of Highly Polarized Positrons Using Polarized Electrons at MeV Energies, Phys. Rev. Lett. 116, 214801 (2016). https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.116.214801

高功率回旋行波放大器(Gyrotron traveling wave tube amplifier, gyro-TWT)

[1] C. C. Chiu, C.-Y. Tsai, S. H. Kao, K. R. Chu, L. R. Barnett, and N. C. Luhmann, Jr., Study of a High-Order-Mode Gyrotron Traveling-Wave Amplifier, Physics of Plasmas 17, 113104 (2010). https://aip.scitation.org/doi/full/10.1063/1.3505945