4 documents found, page 1 of 1
Experimental study of extended timescale dynamics of a plasma wakefield driven ...
Chappell, J.; Adli, E.; Agnello, R.; Aladi, M.; Andrebe, Y; Apsimon, O.; Apsimon, R.; Bachmann, A.-M.; Baistrukov, M. A.; Batsch, F.; Bergamaschi, M.Plasma wakefield dynamics over timescales up to 800 ps, approximately 100 plasma periods, are studied experimentally at the Advanced Wakefield Experiment (AWAKE). The development of the longitudinal wakefield amplitude driven by a self-modulated proton bunch is measured using the external injection of witness electrons that sample the fields. In simulation, resonant excitation of the wakefield causes plasma ele...
Proton bunch self-modulation in plasma with density gradient
Braunmuller, F.; Nechaeva, T.; Adli, E.; Agnello, R.; Aladi, M.; Andrebe, Y.; Apsimon, O.; Apsimon, R.; Bachmann, A. -M.; Baistrukov, M. A.; Batsch, F.We study experimentally the effect of linear plasma density gradients on the self-modulation of a 400 GeV proton bunch. Results show that a positive or negative gradient increases or decreases the number of microbunches and the relative charge per microbunch observed after 10 m of plasma. The measured modulation frequency also increases or decreases. With the largest positive gradient we observe two frequencies...
Proton beam defocusing in AWAKE: comparison of simulations and measurements
Gorn, A.; Turner, M.; Adli, E; Agnello, R.; Aladi, M.; Andrebe, Y.; Apsimon, O.; Apsimon, R.; Bachmann, A. -M.; Baistrukov, M. A.; Batsch, F.In 2017, AWAKE demonstrated the seeded self-modulation (SSM) of a 400 GeV proton beam from the Super Proton Synchrotron at CERN. The angular distribution of the protons deflected due to SSM is a quantitative measure of the process, which agrees with simulations by the two-dimensional (axisymmetric) particle-in-cell code LCODE to about 5%. The agreement is achieved in beam population scans at two selected plasma...
Experimental study of wakefields driven by a self-modulating proton bunch in pl...
Turner, M.; Muggli, P.; Adli, E.; Agnello, R.; Aladi, M.; Andrebe, Y.; Apsimon, O.; Apsimon, R.; Bachmann, A.-M.; Baistrukov, M. A.; Batsch, F.We study experimentally the longitudinal and transverse wakefields driven by a highly relativistic proton bunch during self-modulation in plasma. We show that the wakefields’ growth and amplitude increase with increasing seed amplitude as well as with the proton bunch charge in the plasma. We study transverse wakefields using the maximum radius of the proton bunch distribution measured on a screen downstream fr...