TY - JOUR

T1 - Amplitude enhancement of the self-modulated plasma wakefields

AU - Li, Y.

AU - Xia, G.

AU - Lotov, K. V.

AU - Sosedkin, A. P.

AU - Zhao, Y.

AU - Gessner, S. J.

PY - 2018/10/5

Y1 - 2018/10/5

N2 - Seeded Self-modulation (SSM) has been demonstrated to transform a long proton bunch into many equidistant micro-bunches (e.g., the AWAKE case), which then resonantly excite strong wakefields. However, the wakefields in a uniform plasma suffer from a quick amplitude drop after reaching the peak. This is caused by a significant decrease of the wake phase velocity during self-modulation. A large number of protons slip out of focusing and decelerating regions and get lost, and thus cannot contribute to the wakefield growth. Previously suggested solutions incorporate a sharp or a linear plasma longitudinal density increase which can compensate the backward phase shift and therefore enhance the wakefields. In this paper, we propose a new plasma density profile, which can further boost the wakefield amplitude by 30%. More importantly, almost 24% of protons initially located along one plasma period survive in a micro-bunch after modulation. The underlying physics is discussed.

AB - Seeded Self-modulation (SSM) has been demonstrated to transform a long proton bunch into many equidistant micro-bunches (e.g., the AWAKE case), which then resonantly excite strong wakefields. However, the wakefields in a uniform plasma suffer from a quick amplitude drop after reaching the peak. This is caused by a significant decrease of the wake phase velocity during self-modulation. A large number of protons slip out of focusing and decelerating regions and get lost, and thus cannot contribute to the wakefield growth. Previously suggested solutions incorporate a sharp or a linear plasma longitudinal density increase which can compensate the backward phase shift and therefore enhance the wakefields. In this paper, we propose a new plasma density profile, which can further boost the wakefield amplitude by 30%. More importantly, almost 24% of protons initially located along one plasma period survive in a micro-bunch after modulation. The underlying physics is discussed.

UR - http://www.scopus.com/inward/record.url?scp=85054903989&partnerID=8YFLogxK

U2 - 10.1088/1742-6596/1067/4/042009

DO - 10.1088/1742-6596/1067/4/042009

M3 - Conference article

AN - SCOPUS:85054903989

VL - 1067

JO - Journal of Physics: Conference Series

JF - Journal of Physics: Conference Series

SN - 1742-6588

IS - 4

M1 - 042009

T2 - 9th International Particle Accelerator Conference, IPAC 2018

Y2 - 29 April 2018 through 4 May 2018

ER -