TY  - CONF
AU  - Shao, J.H.
AU  - Chen, H.B.
AU  - Conde, M.E.
AU  - Doran, D.S.
AU  - Ha, G.
AU  - Jing, C.-J.
AU  - Liu, W.
AU  - Peng, M.M.
AU  - Power, J.G.
AU  - Seok, J.
AU  - Shi, J.
AU  - Whiteford, C.
AU  - Wisniewski, E.E.
AU  - Zha, H.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Generation of High Power Short Rf Pulses using an X-Band Metallic Power Extractor Driven by High Charge Multi-Bunch Train
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - Short pulse two-beam acceleration (TBA) is a structure wakefield acceleration (SWFA) approach aiming to achieve gradient above 250 MV/m using rf pulses less than 20 ns. An X-band 11.7 GHz metallic power extractor has been developed as the power source to test accelerating structures in this extreme regime. The power extractor is designed to be driven by high charge bunches separated by 769.2 ps (9 times the X-band period) on an L-band 1.3 GHz beamline. In the recent experiment, ~280 MW rf pulses with 3 ns flat-top have been measured by a coaxial rf pickup when driven by 8-bunch trains with a total charge of ~500 nC. The power level is ~50% lower than the theoretical prediction and simulation. Experimental investigation suggests that the missing power was mainly caused by the multipacting issue inside the rf pickup, which could be eliminated by a newly-designed directional coupler.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 734
EP  - 737
KW  - pick-up
KW  - experiment
KW  - multipactoring
KW  - acceleration
KW  - simulation
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-MOPRB069
UR  - http://jacow.org/ipac2019/papers/moprb069.pdf
ER  - 

TY  - CONF
AU  - Seok, J.
AU  - Chung, M.
AU  - Conde, M.E.
AU  - Ha, G.
AU  - Power, J.G.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Suppression of Correlated Energy Spread Using Emittance Exchange
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - An emittance exchange (EEX) provides a precise longitudinal phase space manipulation of electron bunch. It has been studied for an easy and precise control of temporal distribution, but controls of energy distribution have not been explored. Since the energy control using EEX is under the identical principle to the temporal control, the EEX beamline can control a correlated energy spread of the electron bunch. This would benefit accelerator facilities requiring a low energy spread such as X-ray Free Electron Laser Oscil-lator (XFELO). In this paper, we present principle and preliminary simulation work on the suppression of correlated energy spread using the EEX beamline. ing the EEX beamline.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 3275
EP  - 3278
KW  - cavity
KW  - linac
KW  - controls
KW  - simulation
KW  - electron
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-WEPTS066
UR  - http://jacow.org/ipac2019/papers/wepts066.pdf
ER  - 

TY  - CONF
AU  - Roussel, R.J.
AU  - Andonian, G.
AU  - Conde, M.E.
AU  - Doran, D.S.
AU  - Ha, G.
AU  - Lynn, W.J.
AU  - Power, J.G.
AU  - Rosenzweig, J.B.
AU  - Seok, J.
AU  - Whiteford, C.
AU  - Wisniewski, E.E.
ED  - Boland, Mark
ED  - Tanaka, Hitoshi
ED  - Button, David
ED  - Dowd, Rohan
ED  - Schaa, Volker RW
ED  - Tan, Eugene
TI  - Transformer Ratio Measurements from Ramped Beams in the Plasma Blowout Regime using Emittance Exchange
J2  - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019
CY  - Melbourne, Australia
T2  - International Particle Accelerator Conference
T3  - 10
LA  - english
AB  - We present initial measurements from a UCLA-Argonne Wakefield Accelerator collaborative plasma wakefield acceleration (PWFA) experiment aimed at demonstrating the dependence of transformer ratio on longitudinal beam shape. The transformer ratio or the ratio between the maximum acceleration of the witness and the maximum deceleration of the drive beam, is key to a mature, beam-based, plasma wakefield accelerator design. Utilizing the unique capabilities of the emittance exchange (EEX) beamline, we may obtain transformer ratios in excess of six in PWFA. We present the experimental beamline design, relevant beam diagnostics and explore preservation of the longitudinal beam profile.
PB  - JACoW Publishing
CP  - Geneva, Switzerland
SP  - 3778
EP  - 3781
KW  - plasma
KW  - wakefield
KW  - emittance
KW  - experiment
KW  - acceleration
DA  - 2019/06
PY  - 2019
SN  - 978-3-95450-208-0
DO  - DOI: 10.18429/JACoW-IPAC2019-THPGW088
UR  - http://jacow.org/ipac2019/papers/thpgw088.pdf
ER  -