TY - CONF AU - Zhu, K. AU - Dou, W.P. AU - Easton, M.J. AU - Gan, P.P. AU - Gao, S.L. AU - He, Y. AU - Li, H.P. AU - Liu, S. AU - Lu, Y.R. AU - Tan, Q.Y. AU - Tao, L. AU - Wang, C. AU - Wang, Z. AU - Wu, Q. AU - Zhao, H.W. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Design and Experiment of a Window-Type CW Deuteron RFQ J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - A deutron CW RFQ was designed and fabricated in Peking University. It will accelerate 50mA CW deutron beam from 50keV to 1MeV at 162.5MHz. The novel structure of four-vane with window was used to seperate the dipole mode from the working mode. The field tuning of this RFQ was different from conventional four vane RFQ because that the four quadrants of RFQ cavity were coupled. The discipline of field tuning was studied by simulation and experiment. The beam dynamics of the RFQ was designed by equipartation and matching method, limit current effect was considered at the same time. The final design result of the RFQ was: voltage between electrodes was 60kV, transport efficiency of RFQ is 98%, field unflatness is less than 2% after tuning, the deformation of RFQcavity is less than 80um. Only 47 hours was spent to increase CW power of cavity from 0 to 55kW in high power test and The RFQ can working stable at the design voltage. The preliminary H²⁺ beam exeperiment has been done and 1.78mA CW beam was obtained at exit of RFQ. This paper will introduce the detail of design and experiment of the RFQ. PB - JACoW Publishing CP - Geneva, Switzerland SP - 1021 EP - 1024 KW - rfq KW - cavity KW - experiment KW - operation KW - Windows DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-MOPTS075 UR - http://jacow.org/ipac2019/papers/mopts075.pdf ER - TY - CONF AU - Luo, X. AU - He, T.H. AU - Lao, C.L. AU - Shan, L.J. AU - Shen, X.M. AU - Wang, F. AU - Wu, D. AU - Zhou, K. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - HOM Analysis of the 4-cell Superconducting Cavity on CTFEL Facility J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - The higher order modes (HOMs) of the 1.3GHz 4-cell cavity on CTFEL facility is analyzed in this paper. The passbands of the HOMs in the 4-cell cavity were simulat-ed, and the most harmful modes were determined. The power of the wakefields was estimated. By microwave test at room temperature, the frequencies of the HOMs were measured, as well as the external Q’s of the HOM cou-plers. Besides, a frequency distribution measurement system was built. The HOM signal excited by beam at 2 K temperature is measured, and some preliminary results are obtained. The measurement techniques and results of the HOM damping performance are presented in this paper. PB - JACoW Publishing CP - Geneva, Switzerland SP - 2918 EP - 2920 KW - HOM KW - cavity KW - FEL KW - simulation KW - electron DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-WEPRB049 UR - http://jacow.org/ipac2019/papers/weprb049.pdf ER - TY - CONF AU - Li, D.Y. AU - Chen, J.E. AU - Geng, Y.X. AU - Hu, X.Y. AU - Li, C.C. AU - Liao, Q. AU - Lin, C. AU - Lu, H.Y. AU - Ma, W.J. AU - Wu, M.J. AU - Xu, X.H. AU - Yan, X.Q. AU - Yang, T. AU - Zhao, Y.Y. AU - Zhu, J.G. AU - Zhu, K. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Applications of Compact Laser Plasma Accelerator (CLAPA) Beamline in Peking University J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - Proton beam with energies less than 10 MeV, <1% energy spread, several to tens of pC charge can be stably produced and transported in Compact LAser Plasma Accelerator (CLAPA) at Peking University. The CLAPA beam line is an object-image point analysing system, which ensures the transmission efficiency and energy selection accuracy for proton beams with initial large divergence angle and energy spread. A spread-out Bragg peak (SOBP) is produced with high precision beam control, which is essential for cancer therapy. Other primary application experiments based on laser-accelerated proton beam have also been carried out, such as proton radiograph, stress testing for tungsten, irradiation of semi-conductor sensor to simulate the space irradiation environment and so on. PB - JACoW Publishing CP - Geneva, Switzerland SP - 3676 EP - 3678 KW - proton KW - laser KW - radiation KW - acceleration KW - plasma DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-THPGW042 UR - http://jacow.org/ipac2019/papers/thpgw042.pdf ER - TY - CONF AU - Liu, F. AU - Huang, S. AU - Liu, K.X. AU - Zhang, S. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - Highly Stable Linearly Polarized Arbitrary Temporal Shaping of Picosecond Laser Pulses J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - This paper reports the study and demonstration of a new variable temporal shaping method capable of generating linearly polarized picosecond laser pulses with arbitrary predefined shapes, which are highly desired by various applications including low emittance high brightness electron bunch generation in photocathode guns. It is found that both high transmittance and high stability of the shaped pulses can be achieved simultaneously when crystals are set at specific phase delay through the fine control of the crystal temperature. Such variable temporal shaping technique may lead to new opportunities for many potential applications over a wide range of laser wavelengths, pulse repetition rates, time structures and power levels, etc. In addition, a new double-pass variable shaping method is also proposed and could significantly simplify the shaper structure and reduce the cost. PB - JACoW Publishing CP - Geneva, Switzerland SP - 3682 EP - 3685 KW - laser KW - controls KW - polarization KW - experiment KW - flattop DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-THPGW044 UR - http://jacow.org/ipac2019/papers/thpgw044.pdf ER - TY - CONF AU - Wang, P.J. AU - Cao, Z.X. AU - Gao, G.Y. AU - Geng, Y.X. AU - Kong, D.F. AU - Lin, C. AU - Liu, JB. AU - Lu, H.Y. AU - Ma, W.J. AU - Mei, Z.S. AU - Pan, Z.P. AU - Shou, Y.R. AU - Wang, D.H. AU - Xu, S.R. AU - Yan, X.Q. AU - Zhao, Y.Y. ED - Boland, Mark ED - Tanaka, Hitoshi ED - Button, David ED - Dowd, Rohan ED - Schaa, Volker RW ED - Tan, Eugene TI - A Simple Way to Introduce an Ajustable Femtosecond Pre-Pulse to Enhance Laser-Driven Proton Acceleration J2 - Proc. of IPAC2019, Melbourne, Australia, 19-24 May 2019 CY - Melbourne, Australia T2 - International Particle Accelerator Conference T3 - 10 LA - english AB - We demonstrate a simple way to introduce a femtosecond pre-pulse with adjustable intensity and delay without using an additional compressor to enhance laser-driven proton acceleration. Targets with different thicknesses were shoot at normal incidence by varying the pre-pulses. Experimental results show that significant enhancement on the proton energy can be achieved when the intensity of pre-pulse is optimized. Density profile of preplasma was obtained by bydrodynamic simulations. PIC simulations reveal that the preplasma generated by a femtosecond pre-pulse can increase the intensity of main pulse. PB - JACoW Publishing CP - Geneva, Switzerland SP - 3686 EP - 3688 KW - target KW - laser KW - proton KW - plasma KW - acceleration DA - 2019/06 PY - 2019 SN - 978-3-95450-208-0 DO - DOI: 10.18429/JACoW-IPAC2019-THPGW045 UR - http://jacow.org/ipac2019/papers/thpgw045.pdf ER -