Experimental Physics Division (EPD) seminar 
Title I: Proton-driven plasma wakefield acceleration (AWAKE), current status and future plans 
Title II: Plasma beam dump-towards a compact future accelerator 
Speaker: Dr. Guoxing Xia (the University of Manchester and the Cockroft Institute) 
Time: 09:30, Friday 28th December 2018 
Location: B326 main building 
Indico: https://indico.ihep.ac.cn/event/9158/ 

Abstract I: Proton-driven plasma wakefield acceleration (AWAKE), current status and future plans 
Plasma-based accelerators have achieved tremendous progress in the last three decades, thanks to the availability of ultrashort and high power lasers and relativistic electron beams. Nowadays, laser wakefield acceleration (LWFA) has routinely achieved GeV beam energy in centimeter long plasma channel. Electron beam driven plasma wakefield acceleration (PWFA) has achieved the energy doubling of a 42 GeV SLC electron beam at SLAC and proved the high efficiency acceleration for electrons and positrons, respectively. The new plasma-based acceleration experiment, so-called AWAKE at CERN has very recently demonstrated the successful acceleration of electrons to up to 2 GeV in a proton driven plasma wakefield. In this talk, I will introduce the basic principles and the development of proton-driven plasma wakefield acceleration scheme. The latest experimental results and its future plans. 
References: 
[1] AWAKE Collaboration, Acceleration of electrons in the plasma wakefield of a proton bunch, Nature 561, 363-367 (2018). 
[2] AWAKE Collaboration, Experimental observation of proton bunch modulation in a plasma, at varying plasma densities, accepted to be published in Phys. Rev. Lett. (2018). 
[3] AWAKE Collaboration, Experimental observation of plasma wakefield growth driven by the seeded self-modulation of a proton bunch, accepted to be published in Phys. Rev. Lett. (2018). 

Abstract II: Plasma beam dump-towards a compact future accelerator 
Plasma wakefield can be used to accelerate the particle bunch to high energies in relatively short distances. Meanwhile the plasma wakefield can also be utilized to decelerate the particle bunches more efficiently than the conventional beam dump facilities. Our recent studies show that a properly designed plasma beam dump can effectively absorb the beam energy in a much compact setup. The other advantage of plasma beam dump lies in the fact that the resultant products after beam dump have much less radioactive hazards, compared to conventional material based beam dumps. An international consortium has been initiated to study this plasma beam dump effect with the aims to achieving the compact future accelerator and the possibility to recycle the energy from plasma. 
Reference: 
[1] K. Hanahoe, G. Xia et al., Simulation study of a passive plasma beam dump using varying plasma density, Physics of Plasmas 24, 023120 (2017); https://doi.org/10.1063/1.4977449.