IPAC2013 - List of Keywords (accelerating-gradient)

Paper	Title	Other Keywords	Page
MOPEA040	Study of Geometry Dependent Multipacting of a Superconducting QWR	electron, simulation, cavity, vacuum	166
	K. Zhou, X.Y. Lu, X. Luo, S.W. Quan, L. Yang, Z.Y. Yao PKU, Beijing, People's Republic of China
	Funding: The Major Research Plan of National Natural Science Foundation of China A superconducting quarter wave resonator (QWR) of frequency=162.5 MHz and β=0.085 has been designed at Peking University. This paper focus on the multipacting (MP) study for the QWR with CST Particle Studio. The simulation results for the initial designed model reveal that there is no sign of MP with its normal operating accelerating gradients in the range of 6-8 MV/m. The accelerating gradient range that may incur MP is from about 1.4 MV/m to 3.2 MV/m, and the places where MP may be encountered are mainly located at the top part of the QWR. So the effect of different top geometries on MP has also been studied in depth. Our results show that inward convex round roof is better than other round roofs, and plane roofs have an obvious advantage over round roofs on the suppression of MP in general. While considering the optimization of its electromagnetic (EM) design, our initial designed model is also acceptable.

MOPWA038	Flashbox Compact Beam Spectrometer and its Application to the High-gradient Acceleration Study	electron, ion, dipole, acceleration	753
	A. Dubrovskiy, F. Tecker CERN, Geneva, Switzerland M. Jacewicz, R.J.M.Y. Ruber, V.G. Ziemann Uppsala University, Uppsala, Sweden
	A Flashbox compact spectrometer has been developed for the Two-beam Test Stand (TBTS), which is a part of the CLIC test facility CTF3 at CERN. It is used to study limitations of high-gradient acceleration in X-band structures being prototyped in the TBTS. The Flashbox is built around the beam tube such that an electron beam can pass to be accelerated in the X-band structure while charged particles emitted from the accelerating structure can be intercepted on the spectrometer consisting of detector plates aligned along the beam axis in combination with magnetic and electric fields. The Flashbox has made it possible to identify electrons and ions emitted by the accelerating structure during RF breakdown. We describe the Flashbox and first results.

TUPEA057	Optimization of Rectangular Dielectric Structures for the Planned Wakefield Acceleration Experiments in KIPT	wakefield, electron, acceleration, vacuum	1262
	G.V. Sotnikov, K.V. Galaydych, V. Kiselev, P.I. Markov, I.N. Onishchenko NSC/KIPT, Kharkov, Ukraine
	Funding: This study is supported by Global Initiatives for Proliferation Prevention (GIPP) program, project ANL-T2-247-UA (STCU Agreement P522). We, at the Kharkov Institute of Physics and Technology, planned experimental test of the basic principles of the multi-bunch multi-mode wakefield accelerator. For this purpose we carried out a series of calculations of wakefield excitation and dynamics of the drive and witness bunches in rectangular structures with a dielectric substrate. For optimization two rectangular vacuum waveguides of R32 (72.14mm x 34.04mm) and R26 (86.36mm x 43.18mm) which were filled with the dielectric covering two any opposite metal walls of a waveguide were chosen. As possible dielectric Alumina, Cordierite, or Teflon were tested. It was supposed that the structure will be energized by sequence of electron bunches (bunch repetition frequency is 2.805 GHz), having energy of 4.5 MeV. As the candidate for operating mode LSM-wave or LSE-wave, with frequency to equal the bunch repetition frequency or its doubled frequency were tested. The gradient of an accelerating field, small transverse deflection (or divergence) of drive and witness bunches were the main criteria of optimization. As a result of optimization we propose some dielectric structures for future wakefield experiments in KIPT.

TUPME026	Optimization on RF parameters of a Choke-Mode Structure for the Clic Main LINAC	wakefield, simulation, linac, cavity	1628
	H. Zha, H.B. Chen, J. Shi TUB, Beijing, People's Republic of China
	Funding: This work was support by the National Natural Science Foundation of China (Grant No. 11135004). A tapered choke-mode structure for the main linac of Compact Linear Collider (CLIC) had been designed. Wakefield suppression of this structure fits the beam dynamic requirements. But it has a lower RF performance compared to the baseline design of CLIC main linac. A genetic algorithm is used in the procedure to find the optimum solution. A new choke-mode structure with 24 regular cells working on 100MV/m has been design, which fits beam dynamic constraints and has higher RF efficiency and lower surface field.

WEPWO013	High Power Tests of Injector Cryomodule for Compact-ERL	cavity, cryomodule, HOM, radiation	2340
	E. Kako, D.A. Arakawa, K. Hara, T. Honma, H. Katagiri, Y. Kojima, Y. Kondo, S. Michizono, T. Miura, H. Nakai, H. Nakajima, K. Nakanishi, S. Noguchi, T. Shishido, T. Takenaka, K. Watanabe, Y. Yamamoto KEK, Ibaraki, Japan H. Hara, H. Hitomi, K. Sennyu MHI, Kobe, Japan
	In the cERL injector cryomodule, electron beams of 10 mA are accelerated from the beam energy of 500 keV to 5 MeV. A three 2-cell cavity system was chosen for the cERL injector. Each cavity is driven by two input couplers to reduce a required RF power handling capacity and also to compensate a coupler kick. In the cERL injector cryomodule, critical hardware components are not superconducting cavities but RF input couplers operating in CW mode. Six input couplers for the installation in the cryomodule were fabricated, and three pairs of input couplers were carefully conditioned. Costruction status, cool-down tests and high power RF test results on injector cryomodule for compact-ERL at KEK will be discussed in this paper.

WEPWO023	High Current Superconducting Cavity Study and Design	cavity, superconducting-cavity, linac, electron	2366
	Z.C. Liu, J. Gao, S. Jin, Y. Liu, J.Y. Zhai, T.X. Zhao, H.J. Zheng IHEP, Beijing, People's Republic of China F. Wang PKU, Beijing, People's Republic of China
	Funding: Project 11275226 supported by NSFC IHEP is developing a new type of high current superconducting cavity called slotted cavity proposed in 2010. The cavity is suitable for accelerating high beam current in Energy Recovery Linac (ERL). The cavity can extremely dump high order modes (HOMs) in the cavity to keep a high beam current threshold in the linac. We have studied and designed a three cell cavity and the fabrication is under going.

Paper

Title

Other Keywords

Page

MOPEA040

Study of Geometry Dependent Multipacting of a Superconducting QWR

electron, simulation, cavity, vacuum

166

K. Zhou, X.Y. Lu, X. Luo, S.W. Quan, L. Yang, Z.Y. Yao
PKU, Beijing, People's Republic of China

Funding: The Major Research Plan of National Natural Science Foundation of China
A superconducting quarter wave resonator (QWR) of frequency=162.5 MHz and β=0.085 has been designed at Peking University. This paper focus on the multipacting (MP) study for the QWR with CST Particle Studio. The simulation results for the initial designed model reveal that there is no sign of MP with its normal operating accelerating gradients in the range of 6-8 MV/m. The accelerating gradient range that may incur MP is from about 1.4 MV/m to 3.2 MV/m, and the places where MP may be encountered are mainly located at the top part of the QWR. So the effect of different top geometries on MP has also been studied in depth. Our results show that inward convex round roof is better than other round roofs, and plane roofs have an obvious advantage over round roofs on the suppression of MP in general. While considering the optimization of its electromagnetic (EM) design, our initial designed model is also acceptable.

MOPWA038

Flashbox Compact Beam Spectrometer and its Application to the High-gradient Acceleration Study

electron, ion, dipole, acceleration

753

A. Dubrovskiy, F. Tecker
CERN, Geneva, Switzerland
M. Jacewicz, R.J.M.Y. Ruber, V.G. Ziemann
Uppsala University, Uppsala, Sweden

A Flashbox compact spectrometer has been developed for the Two-beam Test Stand (TBTS), which is a part of the CLIC test facility CTF3 at CERN. It is used to study limitations of high-gradient acceleration in X-band structures being prototyped in the TBTS. The Flashbox is built around the beam tube such that an electron beam can pass to be accelerated in the X-band structure while charged particles emitted from the accelerating structure can be intercepted on the spectrometer consisting of detector plates aligned along the beam axis in combination with magnetic and electric fields. The Flashbox has made it possible to identify electrons and ions emitted by the accelerating structure during RF breakdown. We describe the Flashbox and first results.

TUPEA057

Optimization of Rectangular Dielectric Structures for the Planned Wakefield Acceleration Experiments in KIPT

wakefield, electron, acceleration, vacuum

1262

G.V. Sotnikov, K.V. Galaydych, V. Kiselev, P.I. Markov, I.N. Onishchenko
NSC/KIPT, Kharkov, Ukraine

Funding: This study is supported by Global Initiatives for Proliferation Prevention (GIPP) program, project ANL-T2-247-UA (STCU Agreement P522).
We, at the Kharkov Institute of Physics and Technology, planned experimental test of the basic principles of the multi-bunch multi-mode wakefield accelerator. For this purpose we carried out a series of calculations of wakefield excitation and dynamics of the drive and witness bunches in rectangular structures with a dielectric substrate. For optimization two rectangular vacuum waveguides of R32 (72.14mm x 34.04mm) and R26 (86.36mm x 43.18mm) which were filled with the dielectric covering two any opposite metal walls of a waveguide were chosen. As possible dielectric Alumina, Cordierite, or Teflon were tested. It was supposed that the structure will be energized by sequence of electron bunches (bunch repetition frequency is 2.805 GHz), having energy of 4.5 MeV. As the candidate for operating mode LSM-wave or LSE-wave, with frequency to equal the bunch repetition frequency or its doubled frequency were tested. The gradient of an accelerating field, small transverse deflection (or divergence) of drive and witness bunches were the main criteria of optimization. As a result of optimization we propose some dielectric structures for future wakefield experiments in KIPT.

TUPME026

Optimization on RF parameters of a Choke-Mode Structure for the Clic Main LINAC

wakefield, simulation, linac, cavity

1628

H. Zha, H.B. Chen, J. Shi
TUB, Beijing, People's Republic of China

Funding: This work was support by the National Natural Science Foundation of China (Grant No. 11135004).
A tapered choke-mode structure for the main linac of Compact Linear Collider (CLIC) had been designed. Wakefield suppression of this structure fits the beam dynamic requirements. But it has a lower RF performance compared to the baseline design of CLIC main linac. A genetic algorithm is used in the procedure to find the optimum solution. A new choke-mode structure with 24 regular cells working on 100MV/m has been design, which fits beam dynamic constraints and has higher RF efficiency and lower surface field.

WEPWO013

High Power Tests of Injector Cryomodule for Compact-ERL

cavity, cryomodule, HOM, radiation

2340

E. Kako, D.A. Arakawa, K. Hara, T. Honma, H. Katagiri, Y. Kojima, Y. Kondo, S. Michizono, T. Miura, H. Nakai, H. Nakajima, K. Nakanishi, S. Noguchi, T. Shishido, T. Takenaka, K. Watanabe, Y. Yamamoto
KEK, Ibaraki, Japan
H. Hara, H. Hitomi, K. Sennyu
MHI, Kobe, Japan

In the cERL injector cryomodule, electron beams of 10 mA are accelerated from the beam energy of 500 keV to 5 MeV. A three 2-cell cavity system was chosen for the cERL injector. Each cavity is driven by two input couplers to reduce a required RF power handling capacity and also to compensate a coupler kick. In the cERL injector cryomodule, critical hardware components are not superconducting cavities but RF input couplers operating in CW mode. Six input couplers for the installation in the cryomodule were fabricated, and three pairs of input couplers were carefully conditioned. Costruction status, cool-down tests and high power RF test results on injector cryomodule for compact-ERL at KEK will be discussed in this paper.

WEPWO023

High Current Superconducting Cavity Study and Design

cavity, superconducting-cavity, linac, electron

2366

Z.C. Liu, J. Gao, S. Jin, Y. Liu, J.Y. Zhai, T.X. Zhao, H.J. Zheng
IHEP, Beijing, People's Republic of China
F. Wang
PKU, Beijing, People's Republic of China

Funding: Project 11275226 supported by NSFC
IHEP is developing a new type of high current superconducting cavity called slotted cavity proposed in 2010. The cavity is suitable for accelerating high beam current in Energy Recovery Linac (ERL). The cavity can extremely dump high order modes (HOMs) in the cavity to keep a high beam current threshold in the linac. We have studied and designed a three cell cavity and the fabrication is under going.