IPAC2015 - List of Authors (Liu, S.)

Paper	Title	Page
MOPHA007	Modeling/Measurement Comparison of Signal Collection in Diamond Sensors in Extreme Conditions	787
	V. Kubytskyi, P. Bambade, S. Liu LAL, Orsay, France
	Here we present a study of charge collection dynamics in a Diamond Sensor (DS) subjected to intensities from 1 to 10⁸ Minimum Ionizing Particles (MIP). We developed a model based on the numerical solution of the 1D drift-diffusion equations, using the Scharfetter-Gummel discretization scheme. Inhomogeneity of the space-charge distribution together with the externally applied electric field are taken into account by analytically solving the Poisson equation at each time step. We identified two regimes of charge collection. The first corresponds to 1-10⁵ MIPs, in this case the externally applied electric field is negligibly perturbed by space-charge effects during the separation of the electron/hole clouds. The second corresponds to intensities larger than 10⁷ MIPs, where the space-charge effects significantly slow down the charge collection due to large concentrations of electron/hole pairs in the DS volume. The results of our modeling are in qualitative agreement with the experimental data acquired at the PHoto-Injector electron beam facility at LAL. Our model allows optimizing DS parameters to achieve desired charge collection times for different beam intensities.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPHA007
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MOPHA008	Investigation of Beam Halo Using In Vacuum Diamond Sensor at ATF2	791
	S. Liu, P. Bambade, F. Bogard, P. Cornebise, V. Kubytskyi, C. Sylvia LAL, Orsay, France A. Faus-Golfe, N. Fuster-Martínez IFIC, Valencia, Spain T. Tauchi, N. Terunuma KEK, Ibaraki, Japan T. Tauchi, N. Terunuma Sokendai, Ibaraki, Japan
	Funding: Chinese Scholarship Council, CNRS and P2IO LABEX Beam halo transverse distribution measurements are of great importance for the understanding of background sources of the nano-meter beam size monitor at the interaction point (IPBSM) of ATF2. One of the most critical issues for the beam halo measurement is to reach high dynamic range. Two in vacuum diamond sensor beam halo scanners (DSv) with four strips each have been developed for the investigation of beam halo transverse distributions at ATF2. The first DSv was installed for horizontal beam halo scanning after the interaction point (IP) of ATF2, in Nov. 2014. It aims to measure the beam halo distribution with large dynamic range (~10⁶), and investigate the possibility of probing the Compton recoil electrons produced in the interaction with the IPBSM laser beams. Studies to characterize the DS performance and measurements of horizontal beam halo performed in Nov.-Dec. 2014 are presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPHA008
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TUPTY019	Realistic Beam Halo Model study in the Extraction Line of ATF2	2038
	N. Fuster-Martínez, A. Faus-Golfe IFIC, Valencia, Spain P. Bambade, S. Liu, S. Wallon LAL, Orsay, France K. Kubo, T. Okugi, T. Tauchi, N. Terunuma KEK, Ibaraki, Japan E. Marín, G.R. White SLAC, Menlo Park, California, USA
	Funding: Work supported by IDC-20101074, FPA2013-47883-C2-1-P and ANR-11-IDEX-0003-02 The understanding and control of the transverse beam halo distributions is an important issue to reduce sources of background noise in Future Linear Colliders (FLC) and specifically at ATF2. A realistic model of the beam halo in the old extraction line of the ATF damping ring was obtained in 2005, based on wire scanner measurements. Recently, new measurements were done in the new extraction line of ATF2, using both wire scanners, in 2013, and Optical Transition Radiation monitors (OTR), in 2014. The beam halo propagation through the ATF2 beamline by means of tracking simulations has been investigated using as input a purely Gaussian and uniform beam halo model.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPTY019
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WEPMN059	Design Study and Construction of a Transverse Beam Halo Collimation System for ATF2	3062
	N. Fuster-Martínez, A. Faus-Golfe IFIC, Valencia, Spain P. Bambade, S. Liu, S. Wallon LAL, Orsay, France K. Kubo, T. Okugi, T. Tauchi, N. Terunuma KEK, Ibaraki, Japan I. Podadera, F. Toral CIEMAT, Madrid, Spain
	Funding: Work supported by IDC-20121074, FPA2013-47883-C2-1-P and ANR-11-IDEX-0003-02 The feasibility and efficiency of a transverse beam halo collimation system for reducing the background in the ATF2 beamline has been studied in simulations. In this paper the design and construction of a retractable transverse beam halo collimator device is presented. The wakefield induced-impact of a realistic mechanical prototype has been studied with CST PS, as well as the wakefield beam dynamics impact by using the tracking code PLACET.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPMN059
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Paper

Title

Page

Modeling/Measurement Comparison of Signal Collection in Diamond Sensors in Extreme Conditions

787

V. Kubytskyi, P. Bambade, S. Liu
LAL, Orsay, France

Here we present a study of charge collection dynamics in a Diamond Sensor (DS) subjected to intensities from 1 to 10⁸ Minimum Ionizing Particles (MIP). We developed a model based on the numerical solution of the 1D drift-diffusion equations, using the Scharfetter-Gummel discretization scheme. Inhomogeneity of the space-charge distribution together with the externally applied electric field are taken into account by analytically solving the Poisson equation at each time step. We identified two regimes of charge collection. The first corresponds to 1-10⁵ MIPs, in this case the externally applied electric field is negligibly perturbed by space-charge effects during the separation of the electron/hole clouds. The second corresponds to intensities larger than 10⁷ MIPs, where the space-charge effects significantly slow down the charge collection due to large concentrations of electron/hole pairs in the DS volume. The results of our modeling are in qualitative agreement with the experimental data acquired at the PHoto-Injector electron beam facility at LAL. Our model allows optimizing DS parameters to achieve desired charge collection times for different beam intensities.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPHA007

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPHA008

Investigation of Beam Halo Using In Vacuum Diamond Sensor at ATF2

791

S. Liu, P. Bambade, F. Bogard, P. Cornebise, V. Kubytskyi, C. Sylvia
LAL, Orsay, France
A. Faus-Golfe, N. Fuster-Martínez
IFIC, Valencia, Spain
T. Tauchi, N. Terunuma
KEK, Ibaraki, Japan
T. Tauchi, N. Terunuma
Sokendai, Ibaraki, Japan

Funding: Chinese Scholarship Council, CNRS and P2IO LABEX
Beam halo transverse distribution measurements are of great importance for the understanding of background sources of the nano-meter beam size monitor at the interaction point (IPBSM) of ATF2. One of the most critical issues for the beam halo measurement is to reach high dynamic range. Two in vacuum diamond sensor beam halo scanners (DSv) with four strips each have been developed for the investigation of beam halo transverse distributions at ATF2. The first DSv was installed for horizontal beam halo scanning after the interaction point (IP) of ATF2, in Nov. 2014. It aims to measure the beam halo distribution with large dynamic range (~10⁶), and investigate the possibility of probing the Compton recoil electrons produced in the interaction with the IPBSM laser beams. Studies to characterize the DS performance and measurements of horizontal beam halo performed in Nov.-Dec. 2014 are presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPHA008

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPTY019

Realistic Beam Halo Model study in the Extraction Line of ATF2

2038

N. Fuster-Martínez, A. Faus-Golfe
IFIC, Valencia, Spain
P. Bambade, S. Liu, S. Wallon
LAL, Orsay, France
K. Kubo, T. Okugi, T. Tauchi, N. Terunuma
KEK, Ibaraki, Japan
E. Marín, G.R. White
SLAC, Menlo Park, California, USA

Funding: Work supported by IDC-20101074, FPA2013-47883-C2-1-P and ANR-11-IDEX-0003-02
The understanding and control of the transverse beam halo distributions is an important issue to reduce sources of background noise in Future Linear Colliders (FLC) and specifically at ATF2. A realistic model of the beam halo in the old extraction line of the ATF damping ring was obtained in 2005, based on wire scanner measurements. Recently, new measurements were done in the new extraction line of ATF2, using both wire scanners, in 2013, and Optical Transition Radiation monitors (OTR), in 2014. The beam halo propagation through the ATF2 beamline by means of tracking simulations has been investigated using as input a purely Gaussian and uniform beam halo model.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPTY019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMN059

Design Study and Construction of a Transverse Beam Halo Collimation System for ATF2

3062

N. Fuster-Martínez, A. Faus-Golfe
IFIC, Valencia, Spain
P. Bambade, S. Liu, S. Wallon
LAL, Orsay, France
K. Kubo, T. Okugi, T. Tauchi, N. Terunuma
KEK, Ibaraki, Japan
I. Podadera, F. Toral
CIEMAT, Madrid, Spain

Funding: Work supported by IDC-20121074, FPA2013-47883-C2-1-P and ANR-11-IDEX-0003-02
The feasibility and efficiency of a transverse beam halo collimation system for reducing the background in the ATF2 beamline has been studied in simulations. In this paper the design and construction of a retractable transverse beam halo collimator device is presented. The wakefield induced-impact of a realistic mechanical prototype has been studied with CST PS, as well as the wakefield beam dynamics impact by using the tracking code PLACET.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPMN059

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)