IPAC2017 - List of Authors (Blomley, E.)

Paper	Title	Page
MOOCB1	Time-Resolved Energy Spread Studies at the ANKA Storage Ring	53
	B. Kehrer, E. Blomley, M. Brosi, E. Bründermann, A.-S. Müller, M.J. Nasse, M. Schedler, M. Schuh, M. Schwarz, P. Schönfeldt, N.J. Smale, J.L. Steinmann KIT, Karlsruhe, Germany N. Hiller PSI, Villigen PSI, Switzerland P. Schütze DESY, Hamburg, Germany
	Funding: This work has been supported by the Initiative and Networking Fund the Helmholtz Association under contract number VH-NG-320 and the BMBF under contract numbers 05K13VKA and 05K16VKA. Recently, a new setup for measuring the beam energy spread has been commissioned at the ANKA storage ring at the Karlsruhe Institute of Technology. This setup is based on a fast-gated intensified camera and detects the horizontal profiles of individual bunches in a multi-bunch environment on a single-turn base. As the radiation source point is located in a dispersive section of the storage ring, this allows time-resolved studies of the energy spread. These studies are of particular interest in the framework of short-bunch beam dynamics and the characterization of instabilities. The system is fully synchronized to other beam diagnostics devices allocated in various places along the storage ring, such as the single-shot electro-optical spectral decoding setup or the turn-by-turn terahertz detection systems. Here we discuss the results of the synchronous measurements with the various systems with special emphasis on the energy spread studies.
	Slides MOOCB1 [6.514 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOOCB1
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MOPAB055	Towards Near-Field Electro-Optical Bunch Profile Monitoring in a Multi-Bunch Environment	227
	P. Schönfeldt, E. Blomley, E. Bründermann, M. Caselle, S. Funkner, N. Hiller, B. Kehrer, A.-S. Müller, M.J. Nasse, G. Niehues, L. Rota, M. Schedler, M. Schuh, M. Weber KIT, Karlsruhe, Germany
	Funding: This work is funded by the BMBF contract numbers: 05K13VKA and 05K16VKA. For electron accelerators, electro-optical methods in the near-field have been shown to be a powerful tool to detect longitudinal bunch profiles. In 2013, we demonstrated for the first time, electro-optical bunch profile measurements in a storage ring at the accelerator test facility and synchrotron light source ANKA at the Karlsruhe Institute of Technology (KIT). To study possible bunch-bunch interactions and its effects on the longitudinal dynamics, these measurements need to be performed in a multi-bunch environment. Up to now, due to long-ranging wake-fields the electro-optical monitoring was limited to single-bunch operation. Here, we present our new in-vacuum setup to overcome this limitation. First measurements show reduced wake-fields in particular around 2 ns, where the subsequent bunch can occur in a multi-bunch environment at ANKA.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB055
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MOPAB056	4-Channel Single Shot and Turn-by-Turn Spectral Measurements of Bursting CSR	231
	J.L. Steinmann, E. Blomley, M. Brosi, E. Bründermann, M. Caselle, B. Kehrer, A.-S. Müller, L. Rota, M. Schuh, P. Schönfeldt, M. Siegel, M. Weber KIT, Karlsruhe, Germany
	The test facility and synchrotron radiation source ANKA at the Karlsruhe Institute of Technology (KIT) in Karlsruhe, Germany, can be operated in a short-bunch mode. Above a threshold current, the high charge density leads to microwave instabilities and the formation of sub-structures. These time-varying sub-structures on bunches of picosecond duration lead to the observation of bursting coherent synchrotron radiation (CSR) in the terahertz (THz) frequency range. The spectral information in this range contains valuable information about the bunch length, shape and sub-structures. We present recent measurements of a spectrometer setup that consists of 4 ultra-fast THz detectors, sensitive in different frequency bands, combined with the KAPTURE readout system developed at KIT for studies requiring high data throughput. This setup allows to record continuously the spectral information on a bunch-by-bunch and turn-by-turn basis. This contribution describes the potential of time-resolved spectral measurements of the short-bunch beam dynamics.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB056
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WEPAB011	High Order Magnetic Field Components and Non-Linear Optics at the ANKA Storage Ring	2586
	A.I. Papash, E. Blomley, J. Gethmann, E. Huttel, A.-S. Müller, M. Schuh KIT, Karlsruhe, Germany
	The Karlsruhe Institute of technology operates the 2.5 GeV electron storage ring ANKA as an accelerator test facility and synchrotron radiation source. A superconducting wiggler is installed in a short straight section of the ring where vertical beta-function is large (13 m). The life time of the electron beam was reduced from 15 to 12 hours at a high field level of the wiggler (2.5 T) even though the coherent shift of vertical tune was compensated locally. Computer simulations show the non-linear nature of the effect. The ANKA storage ring operates with strong sextupoles at a positive chromaticity of +2/+6. Even residual octupole components of the wiggler field, set at the tolerance limit of fabrication conditions, could reduce the dynamic aperture for off-momentum particles providing the betatron tune is located in the vicinity of a weak octupole resonance and the chromaticity is high. Also the vertical betatron tune is close to the sextupole resonance Qy=8/3. Large resonance stop-band and proximity of sextupole resonance affect the life time as well. Betatron tunes of ANKA have been shifted away of suspected high-order resonances and beam life time was essentially improved.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPAB011
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WEPIK068	Non-Linear Beam Dynamics Studies of the CLIC Damping Wiggler Prototype	3087
	J. Gethmann, A. Bernhard, E. Blomley, E. Huttel, A.-S. Müller, A.I. Papash, M. Schedler KIT, Karlsruhe, Germany Y. Papaphilippou, P. Zisopoulos CERN, Geneva, Switzerland K. Zolotarev BINP SB RAS, Novosibirsk, Russia
	Funding: Julian Gethmann acknowledges the support by the DFG-funded Doctoral School Karlsruhe School of Elementary and Astroparticle Physics: Science and Technology First beam dynamics studies of a damping wiggler prototype for the CLIC damping rings have been carried out at the KIT storage ring. Effects of the 2.9 T superconducting wiggler on the electron beam in the 2.5 GeV standard operation mode have been measured and compared with theoretical predictions. Higher order multipole components were investigated using local orbit bump measurements. Based on these findings the simulation models for the storage ring optic have been adjusted. The refined optics model has been applied to the 1.3 GeV, low-operation case. This case will be used to experimentally benchmark beam dynamics simulations involving strong wiggler fields and dominant collective effects. We present these measurements, comparisons and the findings of the simulations with the updated low-mode optics model.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPIK068
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THOBA1	Studies of the Micro-Bunching Instability in Multi-Bunch Operation at the ANKA Storage Ring	3645
SUSPSIK058	use link to see paper's listing under its alternate paper code
	M. Brosi, E. Blomley, E. Bründermann, M. Caselle, B. Kehrer, A. Kopmann, A.-S. Müller, L. Rota, M. Schedler, M. Schuh, M. Schwarz, P. Schönfeldt, J.L. Steinmann, M. Weber KIT, Karlsruhe, Germany
	Funding: Supported by the German Federal Ministry of Education and Research (05K13VKA & 05K16VKA), the Helmholtz Association (VH-NG-320) and the Helmholtz International Research School for Teratronics (HIRST) The test facility and synchrotron light source ANKA at the Karlsruhe Institute of Technology (KIT) operates in the energy range from 0.5 to 2.5 GeV and can generate brilliant coherent synchrotron radiation (CSR) in the THz range employing a dedicated bunch length-reducing optic at 1.3 GeV beam energy. The high degree of spatial compression leads to complex longitudinal dynamics and to time evolving sub-structures in the longitudinal phase space of the electron bunches. The results of the micro-bunching instability are time-dependent fluctuations and strong bursts in the radiated THz power. To study these fluctuations in the emitted THz radiation simultaneously for each individual bunch in a multi-bunch environment, fast THz detectors are combined with KAPTURE, the dedicated KArlsruhe Pulse Taking and Ultrafast Readout Electronics system, developed at KIT. In this contribution we present measurements conducted to study possible multi-bunch effects on the characteristic bursting behavior of the micro-bunch instability.
	Slides THOBA1 [12.910 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THOBA1
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Time-Resolved Energy Spread Studies at the ANKA Storage Ring

53

B. Kehrer, E. Blomley, M. Brosi, E. Bründermann, A.-S. Müller, M.J. Nasse, M. Schedler, M. Schuh, M. Schwarz, P. Schönfeldt, N.J. Smale, J.L. Steinmann
KIT, Karlsruhe, Germany
N. Hiller
PSI, Villigen PSI, Switzerland
P. Schütze
DESY, Hamburg, Germany

Funding: This work has been supported by the Initiative and Networking Fund the Helmholtz Association under contract number VH-NG-320 and the BMBF under contract numbers 05K13VKA and 05K16VKA.
Recently, a new setup for measuring the beam energy spread has been commissioned at the ANKA storage ring at the Karlsruhe Institute of Technology. This setup is based on a fast-gated intensified camera and detects the horizontal profiles of individual bunches in a multi-bunch environment on a single-turn base. As the radiation source point is located in a dispersive section of the storage ring, this allows time-resolved studies of the energy spread. These studies are of particular interest in the framework of short-bunch beam dynamics and the characterization of instabilities. The system is fully synchronized to other beam diagnostics devices allocated in various places along the storage ring, such as the single-shot electro-optical spectral decoding setup or the turn-by-turn terahertz detection systems. Here we discuss the results of the synchronous measurements with the various systems with special emphasis on the energy spread studies.

Slides MOOCB1 [6.514 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOOCB1

Export •

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

MOPAB055

Towards Near-Field Electro-Optical Bunch Profile Monitoring in a Multi-Bunch Environment

227

P. Schönfeldt, E. Blomley, E. Bründermann, M. Caselle, S. Funkner, N. Hiller, B. Kehrer, A.-S. Müller, M.J. Nasse, G. Niehues, L. Rota, M. Schedler, M. Schuh, M. Weber
KIT, Karlsruhe, Germany

Funding: This work is funded by the BMBF contract numbers: 05K13VKA and 05K16VKA.
For electron accelerators, electro-optical methods in the near-field have been shown to be a powerful tool to detect longitudinal bunch profiles. In 2013, we demonstrated for the first time, electro-optical bunch profile measurements in a storage ring at the accelerator test facility and synchrotron light source ANKA at the Karlsruhe Institute of Technology (KIT). To study possible bunch-bunch interactions and its effects on the longitudinal dynamics, these measurements need to be performed in a multi-bunch environment. Up to now, due to long-ranging wake-fields the electro-optical monitoring was limited to single-bunch operation. Here, we present our new in-vacuum setup to overcome this limitation. First measurements show reduced wake-fields in particular around 2 ns, where the subsequent bunch can occur in a multi-bunch environment at ANKA.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB055

Export •

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

MOPAB056

4-Channel Single Shot and Turn-by-Turn Spectral Measurements of Bursting CSR

231

J.L. Steinmann, E. Blomley, M. Brosi, E. Bründermann, M. Caselle, B. Kehrer, A.-S. Müller, L. Rota, M. Schuh, P. Schönfeldt, M. Siegel, M. Weber
KIT, Karlsruhe, Germany

The test facility and synchrotron radiation source ANKA at the Karlsruhe Institute of Technology (KIT) in Karlsruhe, Germany, can be operated in a short-bunch mode. Above a threshold current, the high charge density leads to microwave instabilities and the formation of sub-structures. These time-varying sub-structures on bunches of picosecond duration lead to the observation of bursting coherent synchrotron radiation (CSR) in the terahertz (THz) frequency range. The spectral information in this range contains valuable information about the bunch length, shape and sub-structures. We present recent measurements of a spectrometer setup that consists of 4 ultra-fast THz detectors, sensitive in different frequency bands, combined with the KAPTURE readout system developed at KIT for studies requiring high data throughput. This setup allows to record continuously the spectral information on a bunch-by-bunch and turn-by-turn basis. This contribution describes the potential of time-resolved spectral measurements of the short-bunch beam dynamics.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB056

Export •

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

WEPAB011

High Order Magnetic Field Components and Non-Linear Optics at the ANKA Storage Ring

2586

A.I. Papash, E. Blomley, J. Gethmann, E. Huttel, A.-S. Müller, M. Schuh
KIT, Karlsruhe, Germany

The Karlsruhe Institute of technology operates the 2.5 GeV electron storage ring ANKA as an accelerator test facility and synchrotron radiation source. A superconducting wiggler is installed in a short straight section of the ring where vertical beta-function is large (13 m). The life time of the electron beam was reduced from 15 to 12 hours at a high field level of the wiggler (2.5 T) even though the coherent shift of vertical tune was compensated locally. Computer simulations show the non-linear nature of the effect. The ANKA storage ring operates with strong sextupoles at a positive chromaticity of +2/+6. Even residual octupole components of the wiggler field, set at the tolerance limit of fabrication conditions, could reduce the dynamic aperture for off-momentum particles providing the betatron tune is located in the vicinity of a weak octupole resonance and the chromaticity is high. Also the vertical betatron tune is close to the sextupole resonance Qy=8/3. Large resonance stop-band and proximity of sextupole resonance affect the life time as well. Betatron tunes of ANKA have been shifted away of suspected high-order resonances and beam life time was essentially improved.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPAB011

Export •

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

WEPIK068

Non-Linear Beam Dynamics Studies of the CLIC Damping Wiggler Prototype

3087

J. Gethmann, A. Bernhard, E. Blomley, E. Huttel, A.-S. Müller, A.I. Papash, M. Schedler
KIT, Karlsruhe, Germany
Y. Papaphilippou, P. Zisopoulos
CERN, Geneva, Switzerland
K. Zolotarev
BINP SB RAS, Novosibirsk, Russia

Funding: Julian Gethmann acknowledges the support by the DFG-funded Doctoral School Karlsruhe School of Elementary and Astroparticle Physics: Science and Technology
First beam dynamics studies of a damping wiggler prototype for the CLIC damping rings have been carried out at the KIT storage ring. Effects of the 2.9 T superconducting wiggler on the electron beam in the 2.5 GeV standard operation mode have been measured and compared with theoretical predictions. Higher order multipole components were investigated using local orbit bump measurements. Based on these findings the simulation models for the storage ring optic have been adjusted. The refined optics model has been applied to the 1.3 GeV, low-operation case. This case will be used to experimentally benchmark beam dynamics simulations involving strong wiggler fields and dominant collective effects. We present these measurements, comparisons and the findings of the simulations with the updated low-mode optics model.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPIK068

Export •

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

THOBA1

Studies of the Micro-Bunching Instability in Multi-Bunch Operation at the ANKA Storage Ring

3645

SUSPSIK058

use link to see paper's listing under its alternate paper code

M. Brosi, E. Blomley, E. Bründermann, M. Caselle, B. Kehrer, A. Kopmann, A.-S. Müller, L. Rota, M. Schedler, M. Schuh, M. Schwarz, P. Schönfeldt, J.L. Steinmann, M. Weber
KIT, Karlsruhe, Germany

Funding: Supported by the German Federal Ministry of Education and Research (05K13VKA & 05K16VKA), the Helmholtz Association (VH-NG-320) and the Helmholtz International Research School for Teratronics (HIRST)
The test facility and synchrotron light source ANKA at the Karlsruhe Institute of Technology (KIT) operates in the energy range from 0.5 to 2.5 GeV and can generate brilliant coherent synchrotron radiation (CSR) in the THz range employing a dedicated bunch length-reducing optic at 1.3 GeV beam energy. The high degree of spatial compression leads to complex longitudinal dynamics and to time evolving sub-structures in the longitudinal phase space of the electron bunches. The results of the micro-bunching instability are time-dependent fluctuations and strong bursts in the radiated THz power. To study these fluctuations in the emitted THz radiation simultaneously for each individual bunch in a multi-bunch environment, fast THz detectors are combined with KAPTURE, the dedicated KArlsruhe Pulse Taking and Ultrafast Readout Electronics system, developed at KIT. In this contribution we present measurements conducted to study possible multi-bunch effects on the characteristic bursting behavior of the micro-bunch instability.

Slides THOBA1 [12.910 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THOBA1

Export •

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