IPAC2021 - List of Authors (Chaikovska, I.)

Paper	Title	Page
TUXB05	Intense Channeling Radiation as a Tool for a Hybrid Crystal-Based Positron Source for Future Colliders
	L. Bandiera, A. Mazzolari, M. Romagnoni, A.I. Sytov INFN-Ferrara, Ferrara, Italy L. Bomben, V. Mascagna INFN MIB, MILANO, Italy G. Cavoto INFN-Roma, Roma, Italy I. Chaikovska, R. Chehab Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France D. De Salvador Univ. degli Studi di Padova, Padova, Italy L.G. Foggetta INFN/LNF, Frascati, Italy E. Lutsenko, M. Prest Università dell’Insubria & INFN Milano Bicocca, Como, Italy M. Soldani Università degli Studi di Ferrara, Ferrara, Italy V.V. Tikhomirov INP BSU, Minsk, Belarus E. Vallazza INFN-Trieste, Trieste, Italy
	There is a strong need for intense positron sources for future colliders. A crystal-based hybrid positron source could be an alternative to conventional sources based on the e^- conversion into e⁺ in a thick target. The basic idea of the hybrid source is to split the e⁺ converter into a gamma-quanta radiator plus a gamma-to-positron converter. In such a scheme an e^- beam crosses a thin axially oriented crystal with emission of "channeling radiation", characterized by a considerably larger amount of photons w.r.t. standard bremsstrahlung. The net result is an increase in the number of e⁺ produced at the converter target. In the hybrid scheme, only photons reach the converter, thereby reducing the Peak Energy Deposition Density (PEDD) in the target. Here we present the results of a test conducted at the DESY TB with 5.6 GeV e^- interacting with a W crystal. A huge enhancement in the radiated energy and in the photon emission has been recorded and reproduced with Monte Carlo simulations*. This study is relevant for the design of the FCC-ee positron source. Indeed, through Monte Carlo, we also investigated the best parameters of the crystal radiator suited for the FCC-ee e⁺ source. R. Chehab et al. PAC’89,10.1109/PAC.1989.73147 X.Artru et al. NIMB 266 (2008) 3868 * A. Sytov, V. Tikhomirov, L. Bandiera PRAB 22 (2019) 064601
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WEXA03	Physics and Technology Challenges in Generating High Intensity Positron Beams
	I. Chaikovska Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
	Positron sources are essential to the current and future lepton collider projects (ILC, CLIC, SuperKEKB, FCC-ee, etc.) with challenging critical requirements of high-beam intensity and low emittance necessary to achieve high luminosity. In the conventional positron-generation system, a possible scheme to increase the positron intensity is to increase the incident electron beam power (intensity and/or energy). However, the allowable heat load as well as the thermo-mechanical stresses in the target severely limit the allowable beam power of the incident electrons. The positron source community should consolidate the effort and explore different methods of positron production, both classical techniques and especially novel ones, primarily for future high-energy physics applications requiring orders of magnitude higher intensity than what was demonstrated up to now, and for considering future hadronic applications (including the EIC) requiring both polarization and intensity. The studies should be focused on different source types, targets, capture approaches including the existing limitations and potential for polarized positron production identifying the main axes for future R&D.
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WEPAB015	Comparison of Different Matching Device Field Profiles for the FCC-ee Positron Source	2617
	Y. Zhao, L. Ma SDU, Shandong, People’s Republic of China B. Auchmann, P. Craievich, J. Kosse, R. Zennaro PSI, Villigen PSI, Switzerland I. Chaikovska, R. Chehab Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France S. Döbert, A. Latina CERN, Geneva, Switzerland P.V. Martyshkin BINP SB RAS, Novosibirsk, Russia
	In this report, we compared different matching device field profiles for the FCC-ee positron source. The matching device is used to capture positrons with magnetic field. A flux concentrator was designed with a conical inner chamber. A smaller aperture and a larger aperture were studied. An analytic field profile was also studied using an adiabatic formula. The peak field of the analytic profile as well as beam and target parameters was optimised to achieve a maximum positron yield. A safe energy deposition in the target was guaranteed by requiring a constraint on the deposited power and peak energy deposition density.
	Poster WEPAB015 [3.066 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB015
About •	paper received ※ 15 May 2021 paper accepted ※ 23 June 2021 issue date ※ 30 August 2021
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WEPAB117	Injection Feedback for a Storage Ring	2870
	A. Moutardier, C. Bruni, I. Chaikovska, S. Chancé, N. Delerue, E.E. Ergenlik, V. Kubytskyi, H. Monard Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
	Funding: Research Agency under the Equipex convention ANR-10-EQPX-0051. We report on an injection feedback scheme for the ThomX storage ring project. ThomX is a 50-MeV-electron accelerator prototype which will use Compton backscattering in a storage ring to generate a high flux of hard X-rays. Given the slow beam damping (in the ring), the injection must be performed with high accuracy to avoid large betatron oscillations. A homemade analytic code is used to compute the corrections that need to be applied before the beam injection to achieve a beam position accuracy of a few hundred micrometers in the first beam position monitors (BPMs). In order to do so the code needs the information provided by the ring’s diagnostic devices. The iterative feedback system has been tested using MadX simulations. Our simulations show that a performance that matches the BPMs’ accuracy can be achieved in less than 50 iterations in all cases. Details of this feedback algorithm, its efficiency and the simulations are discussed.
	Poster WEPAB117 [2.422 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB117
About •	paper received ※ 28 May 2021 paper accepted ※ 01 July 2021 issue date ※ 25 August 2021
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WEPAB118	Loss Maps Along the ThomX Transfer Line and the Ring First Turn	2874
	A. Moutardier, C. Bruni, I. Chaikovska, S. Chancé, N. Delerue, E.E. Ergenlik, V. Kubytskyi, H. Monard Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
	Funding: Research Agency under the Equipex convention ANR-10-EQPX-0051. We report on studies of the loss maps for particles travelling from the end of the ThomX’s linac along the transfer line to the end of the ring first turn in preparation of the machine commissioning. ThomX is a 50-MeV-electron accelerator prototype which will use Compton backscattering to generate a high flux of hard X-rays. The accelerator tracking code MadX is used to simulate electrons’ propagation and compute losses. These maps may be projected at any localisation along the bunch path or plotted along the bunch path. This information is particularly relevant at the locations of the monitoring devices (screens, position monitors,…) where loss predictions will be compared with measurements.
	Poster WEPAB118 [3.173 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB118
About •	paper received ※ 28 May 2021 paper accepted ※ 28 July 2021 issue date ※ 12 August 2021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

TUXB05

Intense Channeling Radiation as a Tool for a Hybrid Crystal-Based Positron Source for Future Colliders

L. Bandiera, A. Mazzolari, M. Romagnoni, A.I. Sytov
INFN-Ferrara, Ferrara, Italy
L. Bomben, V. Mascagna
INFN MIB, MILANO, Italy
G. Cavoto
INFN-Roma, Roma, Italy
I. Chaikovska, R. Chehab
Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
D. De Salvador
Univ. degli Studi di Padova, Padova, Italy
L.G. Foggetta
INFN/LNF, Frascati, Italy
E. Lutsenko, M. Prest
Università dell’Insubria & INFN Milano Bicocca, Como, Italy
M. Soldani
Università degli Studi di Ferrara, Ferrara, Italy
V.V. Tikhomirov
INP BSU, Minsk, Belarus
E. Vallazza
INFN-Trieste, Trieste, Italy

There is a strong need for intense positron sources for future colliders. A crystal-based hybrid positron source could be an alternative to conventional sources based on the e^- conversion into e⁺ in a thick target. The basic idea of the hybrid source is to split the e⁺ converter into a gamma-quanta radiator plus a gamma-to-positron converter*. In such a scheme an e^- beam crosses a thin axially oriented crystal with emission of "channeling radiation", characterized by a considerably larger amount of photons w.r.t. standard bremsstrahlung**. The net result is an increase in the number of e⁺ produced at the converter target. In the hybrid scheme, only photons reach the converter, thereby reducing the Peak Energy Deposition Density (PEDD) in the target. Here we present the results of a test conducted at the DESY TB with 5.6 GeV e^- interacting with a W crystal. A huge enhancement in the radiated energy and in the photon emission has been recorded and reproduced with Monte Carlo simulations***. This study is relevant for the design of the FCC-ee positron source. Indeed, through Monte Carlo, we also investigated the best parameters of the crystal radiator suited for the FCC-ee e⁺ source.
* R. Chehab et al. PAC’89,10.1109/PAC.1989.73147
** X.Artru et al. NIMB 266 (2008) 3868
*** A. Sytov, V. Tikhomirov, L. Bandiera PRAB 22 (2019) 064601

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WEXA03

Physics and Technology Challenges in Generating High Intensity Positron Beams

I. Chaikovska
Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France

Positron sources are essential to the current and future lepton collider projects (ILC, CLIC, SuperKEKB, FCC-ee, etc.) with challenging critical requirements of high-beam intensity and low emittance necessary to achieve high luminosity. In the conventional positron-generation system, a possible scheme to increase the positron intensity is to increase the incident electron beam power (intensity and/or energy). However, the allowable heat load as well as the thermo-mechanical stresses in the target severely limit the allowable beam power of the incident electrons. The positron source community should consolidate the effort and explore different methods of positron production, both classical techniques and especially novel ones, primarily for future high-energy physics applications requiring orders of magnitude higher intensity than what was demonstrated up to now, and for considering future hadronic applications (including the EIC) requiring both polarization and intensity. The studies should be focused on different source types, targets, capture approaches including the existing limitations and potential for polarized positron production identifying the main axes for future R&D.

Export •

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

WEPAB015

Comparison of Different Matching Device Field Profiles for the FCC-ee Positron Source

2617

Y. Zhao, L. Ma
SDU, Shandong, People’s Republic of China
B. Auchmann, P. Craievich, J. Kosse, R. Zennaro
PSI, Villigen PSI, Switzerland
I. Chaikovska, R. Chehab
Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
S. Döbert, A. Latina
CERN, Geneva, Switzerland
P.V. Martyshkin
BINP SB RAS, Novosibirsk, Russia

In this report, we compared different matching device field profiles for the FCC-ee positron source. The matching device is used to capture positrons with magnetic field. A flux concentrator was designed with a conical inner chamber. A smaller aperture and a larger aperture were studied. An analytic field profile was also studied using an adiabatic formula. The peak field of the analytic profile as well as beam and target parameters was optimised to achieve a maximum positron yield. A safe energy deposition in the target was guaranteed by requiring a constraint on the deposited power and peak energy deposition density.

Poster WEPAB015 [3.066 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB015

About •

paper received ※ 15 May 2021 paper accepted ※ 23 June 2021 issue date ※ 30 August 2021

Export •

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

WEPAB117

Injection Feedback for a Storage Ring

2870

A. Moutardier, C. Bruni, I. Chaikovska, S. Chancé, N. Delerue, E.E. Ergenlik, V. Kubytskyi, H. Monard
Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France

Funding: Research Agency under the Equipex convention ANR-10-EQPX-0051.
We report on an injection feedback scheme for the ThomX storage ring project. ThomX is a 50-MeV-electron accelerator prototype which will use Compton backscattering in a storage ring to generate a high flux of hard X-rays. Given the slow beam damping (in the ring), the injection must be performed with high accuracy to avoid large betatron oscillations. A homemade analytic code is used to compute the corrections that need to be applied before the beam injection to achieve a beam position accuracy of a few hundred micrometers in the first beam position monitors (BPMs). In order to do so the code needs the information provided by the ring’s diagnostic devices. The iterative feedback system has been tested using MadX simulations. Our simulations show that a performance that matches the BPMs’ accuracy can be achieved in less than 50 iterations in all cases. Details of this feedback algorithm, its efficiency and the simulations are discussed.

Poster WEPAB117 [2.422 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB117

About •

paper received ※ 28 May 2021 paper accepted ※ 01 July 2021 issue date ※ 25 August 2021

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

WEPAB118

Loss Maps Along the ThomX Transfer Line and the Ring First Turn

2874

A. Moutardier, C. Bruni, I. Chaikovska, S. Chancé, N. Delerue, E.E. Ergenlik, V. Kubytskyi, H. Monard
Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France

Funding: Research Agency under the Equipex convention ANR-10-EQPX-0051.
We report on studies of the loss maps for particles travelling from the end of the ThomX’s linac along the transfer line to the end of the ring first turn in preparation of the machine commissioning. ThomX is a 50-MeV-electron accelerator prototype which will use Compton backscattering to generate a high flux of hard X-rays. The accelerator tracking code MadX is used to simulate electrons’ propagation and compute losses. These maps may be projected at any localisation along the bunch path or plotted along the bunch path. This information is particularly relevant at the locations of the monitoring devices (screens, position monitors,…) where loss predictions will be compared with measurements.

Poster WEPAB118 [3.173 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB118

About •

paper received ※ 28 May 2021 paper accepted ※ 28 July 2021 issue date ※ 12 August 2021

Export •

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