IPAC2013 - List of Authors (Wu, J.X.)

Paper	Title	Page
MOPME044	A Novel Type of Forward Coupler Slotted Stripline Pickup Electrode for CSRe Stochastic Cooling	571
	J.X. Wu, X.J. Hu, M. Li, J.W. Xia, J.C. Yang, Y. Zhang, G. Zhu IMP, Lanzhou, People's Republic of China F. Caspers CERN, Geneva, Switzerland
	A novel type of slotted or perforated strip-line pick-up or kicker electrode structure for CSRe stochastic cooling for non relativistic particle beams with b=v/c values around 0.7 is presented. This slotted structure is to be used as a forward coupler with the output signal taken from the downstream end and has a rather large relative bandwidth of several octaves. The electrode structure and pickup tank, as well as the beam test result will be presented in this paper.

MOPME045	Design and Test Status of Beam Position Monitors for ADS Injector II Proton LINAC	574
	Y. Zhang, H. Jia, X.C. Kang, M. Li, J.X. Wu, G. Zhu IMP, Lanzhou, People's Republic of China
	Beam Position Monitors (BPM) based on capacitive pick-ups are designed for Accelerator-Driven System (ADS) Injector II proton LINAC. This LINAC is aiming to produce a maximum design current of 15 mA at the 10 MeV energy with an operating frequency of 162.5 MHz. Non-interceptive BPM will be installed to measure the transverse beam position and beam phase in the vacuum chamber. Depending on the location, the response of the BPMs must be optimized for a beam with an energy range from 2.1 up to 10 MeV and an average current between 0.01 and 15 mA. Apart from the broadening of the electromagnetic field due to the low-beta beam, specific issues are affecting some of the BPMs: tiny space in the transport line between the RFQ and the cryomodule and the cryogenic temperature inside the cryomodule. For this reason two types of BPMs are being designed for each location (MEBT and cryomoudle). In this contribution, the present status of the design and measured results for each BPM will be presented in room and cold temperature, focusing on the electromagnetic response for low-beta beams.

THPFI052	Application of Atmospheric Plasma-sprayed Ferrite Layers for Particle Accelerators	3406
	F. Caspers, M. Betz, S. Federmann, M. Taborelli CERN, Geneva, Switzerland K. K., C.A.M. Schulz Surface Engineering Institute, RWTH Aachen University, Aachen, Germany J.X. Wu IMP, Lanzhou, People's Republic of China
	A common problem in all kind of cavity like structures in particle accelerators is the occurrence of RF-resonances. Typically, ferrite plates attached to the walls of such structures like diagnostic devices, kickers or collimators, are used to dampen those undesired modes. However the heat transfer rate from these plates to the walls is rather limited. Brazing ferrite plates to the walls is not possible in most cases due to the different thermal expansion coefficients. To overcome those limitations, atmospheric plasma spraying techniques have been investigated. Ferrite layers with a thickness from 50 micron to about 300 micron can be deposited on metallic surfaces like stainless steel exhibiting good thermal contact and still reasonable absorption properties. In this paper the technological aspects of plasma deposition are discussed and results of specifically developed RF loss measurement procedures for such thin magnetically lossy layers on metal are presented. This kind of layers can also be applied for the production of high temperature RF power loads and related examples will be shown.

Paper

Title

Page

A Novel Type of Forward Coupler Slotted Stripline Pickup Electrode for CSRe Stochastic Cooling

571

J.X. Wu, X.J. Hu, M. Li, J.W. Xia, J.C. Yang, Y. Zhang, G. Zhu
IMP, Lanzhou, People's Republic of China
F. Caspers
CERN, Geneva, Switzerland

A novel type of slotted or perforated strip-line pick-up or kicker electrode structure for CSRe stochastic cooling for non relativistic particle beams with b=v/c values around 0.7 is presented. This slotted structure is to be used as a forward coupler with the output signal taken from the downstream end and has a rather large relative bandwidth of several octaves. The electrode structure and pickup tank, as well as the beam test result will be presented in this paper.

MOPME045

Design and Test Status of Beam Position Monitors for ADS Injector II Proton LINAC

574

Y. Zhang, H. Jia, X.C. Kang, M. Li, J.X. Wu, G. Zhu
IMP, Lanzhou, People's Republic of China

Beam Position Monitors (BPM) based on capacitive pick-ups are designed for Accelerator-Driven System (ADS) Injector II proton LINAC. This LINAC is aiming to produce a maximum design current of 15 mA at the 10 MeV energy with an operating frequency of 162.5 MHz. Non-interceptive BPM will be installed to measure the transverse beam position and beam phase in the vacuum chamber. Depending on the location, the response of the BPMs must be optimized for a beam with an energy range from 2.1 up to 10 MeV and an average current between 0.01 and 15 mA. Apart from the broadening of the electromagnetic field due to the low-beta beam, specific issues are affecting some of the BPMs: tiny space in the transport line between the RFQ and the cryomodule and the cryogenic temperature inside the cryomodule. For this reason two types of BPMs are being designed for each location (MEBT and cryomoudle). In this contribution, the present status of the design and measured results for each BPM will be presented in room and cold temperature, focusing on the electromagnetic response for low-beta beams.

THPFI052

Application of Atmospheric Plasma-sprayed Ferrite Layers for Particle Accelerators

3406

F. Caspers, M. Betz, S. Federmann, M. Taborelli
CERN, Geneva, Switzerland
K. K., C.A.M. Schulz
Surface Engineering Institute, RWTH Aachen University, Aachen, Germany
J.X. Wu
IMP, Lanzhou, People's Republic of China

A common problem in all kind of cavity like structures in particle accelerators is the occurrence of RF-resonances. Typically, ferrite plates attached to the walls of such structures like diagnostic devices, kickers or collimators, are used to dampen those undesired modes. However the heat transfer rate from these plates to the walls is rather limited. Brazing ferrite plates to the walls is not possible in most cases due to the different thermal expansion coefficients. To overcome those limitations, atmospheric plasma spraying techniques have been investigated. Ferrite layers with a thickness from 50 micron to about 300 micron can be deposited on metallic surfaces like stainless steel exhibiting good thermal contact and still reasonable absorption properties. In this paper the technological aspects of plasma deposition are discussed and results of specifically developed RF loss measurement procedures for such thin magnetically lossy layers on metal are presented. This kind of layers can also be applied for the production of high temperature RF power loads and related examples will be shown.