IPAC2022 - Table of Session: FROXGD (Contributed Orals: Beam Instrumentation, Controls, Feedback and Op. Aspects)

Paper	Title	Page
FROXGD1	A Method for Obtaining 3D Charge Density Distribution of a Self-Modulated Proton Bunch	3118
	T. Nechaeva, P. Muggli MPI-P, München, Germany L. Verra, G. Zevi Della Porta CERN, Meyrin, Switzerland L. Verra TUM, Munich, Germany L. Verra MPI, Muenchen, Germany
	The Advanced Wakefield Experiment (AWAKE) at CERN is the first plasma wakefield accelerator experiment to use a proton bunch as driver. The long bunch undergoes seeded self-modulation (SSM) in a 10 m-long plasma. SSM transforms the bunch into a train of short micro-bunches that resonantly drive high-amplitude wakefields. We use optical transition radiation (OTR) and a streak camera to obtain time-resolved images of the bunch transverse charge density distribution in a given plane. In this paper we present a method to obtain 3D images of the bunch by scanning the OTR across the entrance slit of the streak camera. Reconstruction of the 3D distribution is possible because with seeding self-modulation is reproducible. The 3D images allow for checking the axi-symmetry of SSM and for detecting the possible presence of the non-axi-symmetric hosing instability (HI). F. Batsch et al., Phys. Rev. Lett. 126, 164802 (2021).
	Slides FROXGD1 [4.026 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-FROXGD1
About •	Received ※ 20 May 2022 — Revised ※ 15 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 30 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FROXGD2	Development of a Quantum Electron Beam Diagnostic Apparatus
	S. Zhang, A. Camsonne, G.-T. Park JLab, Newport News, Virginia, USA
	Funding: U.S. DOE Contract No. DE-AC05-06OR23177 and Jefferson Lab LDRD program. Characterization of electron beam properties using optical detection methods through the interaction between photons and electrons such as Compton scattering or electro-optic sampling have been successfully implemented as non-invasive diagnostics at various accelerator facilities. However, such methods often suffer from inherently low sensitivity. Here we present the study of a new type of electron beam diagnostic device for direct optical imaging of electron beams at various energy levels. The concept relies on high sensitivity of atoms, prepared in a specific spin quantum superposition, to the perturbations induced by the passing charged particle. Specifically, the magnetic field of the electrons induces polarization change of the probe light as well as changes in light absorption and fluorescence, enabling direct 3D imaging of the charged particles with high resolution. We report our recent experiment results and the design effort on a compact apparatus intended to be tested with the relativistic electron beams at Jefferson Laboratory.
	Slides FROXGD2 [17.656 MB]
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FROXGD3	Injection Beam Measurement Using Synchrotron Radiation Monitor at the SuperKEKB Electron Ring	3121
	H. Ikeda, T.M. Mitsuhashi, G. Mitsuka KEK, Ibaraki, Japan
	We upgraded the diamond mirror of the SuperKEKB electron ring to extract the good quality synchrotron light in 2020 summer. As a result, the accuracy of profile measurement for each bunch using a gate camera has improved dramatically, and it has become possible to measure the incident beam for each turn. The electron beam was injected with single turn injection mode to measure the properties of the beam and measured turn by turn after injection. In order to convert the measurement results into beam size, convolution by diffraction effect and absolute value calibration using real images were performed. We report the behavior of the injection beam during normal operation of SuperKEKB.
	Slides FROXGD3 [5.560 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-FROXGD3
About •	Received ※ 09 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 07 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

A Method for Obtaining 3D Charge Density Distribution of a Self-Modulated Proton Bunch

3118

T. Nechaeva, P. Muggli
MPI-P, München, Germany
L. Verra, G. Zevi Della Porta
CERN, Meyrin, Switzerland
L. Verra
TUM, Munich, Germany
L. Verra
MPI, Muenchen, Germany

The Advanced Wakefield Experiment (AWAKE) at CERN is the first plasma wakefield accelerator experiment to use a proton bunch as driver. The long bunch undergoes seeded self-modulation (SSM) in a 10 m-long plasma. SSM transforms the bunch into a train of short micro-bunches that resonantly drive high-amplitude wakefields. We use optical transition radiation (OTR) and a streak camera to obtain time-resolved images of the bunch transverse charge density distribution in a given plane. In this paper we present a method to obtain 3D images of the bunch by scanning the OTR across the entrance slit of the streak camera. Reconstruction of the 3D distribution is possible because with seeding self-modulation is reproducible*. The 3D images allow for checking the axi-symmetry of SSM and for detecting the possible presence of the non-axi-symmetric hosing instability (HI).
* F. Batsch et al., Phys. Rev. Lett. 126, 164802 (2021).

Slides FROXGD1 [4.026 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-FROXGD1

About •

Received ※ 20 May 2022 — Revised ※ 15 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 30 June 2022

Cite •

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

FROXGD2

Development of a Quantum Electron Beam Diagnostic Apparatus

S. Zhang, A. Camsonne, G.-T. Park
JLab, Newport News, Virginia, USA

Funding: U.S. DOE Contract No. DE-AC05-06OR23177 and Jefferson Lab LDRD program.
Characterization of electron beam properties using optical detection methods through the interaction between photons and electrons such as Compton scattering or electro-optic sampling have been successfully implemented as non-invasive diagnostics at various accelerator facilities. However, such methods often suffer from inherently low sensitivity. Here we present the study of a new type of electron beam diagnostic device for direct optical imaging of electron beams at various energy levels. The concept relies on high sensitivity of atoms, prepared in a specific spin quantum superposition, to the perturbations induced by the passing charged particle. Specifically, the magnetic field of the electrons induces polarization change of the probe light as well as changes in light absorption and fluorescence, enabling direct 3D imaging of the charged particles with high resolution. We report our recent experiment results and the design effort on a compact apparatus intended to be tested with the relativistic electron beams at Jefferson Laboratory.

Slides FROXGD2 [17.656 MB]

Cite •

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

FROXGD3

Injection Beam Measurement Using Synchrotron Radiation Monitor at the SuperKEKB Electron Ring

3121

H. Ikeda, T.M. Mitsuhashi, G. Mitsuka
KEK, Ibaraki, Japan

We upgraded the diamond mirror of the SuperKEKB electron ring to extract the good quality synchrotron light in 2020 summer. As a result, the accuracy of profile measurement for each bunch using a gate camera has improved dramatically, and it has become possible to measure the incident beam for each turn. The electron beam was injected with single turn injection mode to measure the properties of the beam and measured turn by turn after injection. In order to convert the measurement results into beam size, convolution by diffraction effect and absolute value calibration using real images were performed. We report the behavior of the injection beam during normal operation of SuperKEKB.

Slides FROXGD3 [5.560 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-FROXGD3

About •

Received ※ 09 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 07 July 2022

Cite •

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