IPAC2017 - List of Authors (Bauche, J.)

Paper	Title	Page
MOPIK049	SPS Slow Extracted Spill Quality During the 2016 Run	627
	V. Kain, J. Bauche, P. Catherine, K. Cornelis, M.A. Fraser, L. Gatignon, C.M. Genton, B. Goddard, K. Kahle, M. Magrans de Abril, O. Michels, L.S. Stoel, F.M. Velotti CERN, Geneva, Switzerland
	The flux of particles slow extracted with the 1/3 integer resonance from the Super Proton Synchrotron at CERN should ideally be constant over the length of the extraction plateau, for optimum use of the beam by the fixed target experiments. The extracted intensity is controlled in feed-forward correction of the horizontal tune via the main SPS quadrupoles. The Mains power supply noise at 50 Hz and harmonics is also corrected in feed-forward by small amplitude tune modulation at the respective frequencies with a dedicated additional quadrupole circuit. In 2016 the spill quality could be much improved with respect to the situation of the previous year with more performant algorithms. In this paper the improved tools are described and the characteristics of the SPS slow extracted spill in terms of macro structure and typical frequency content are shown. Other sources of perturbation were, however, also present in 2016 which frequently caused the spill quality to be much reduced. The different effects are discussed and possible or actual solutions detailed. Finally, the evolution of the spill quality during characteristic periods in the 2016 run is presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPIK049
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPIK102	Beam Dynamics Studies of the HIE-ISOLDE Transfer Lines in the Presence of Magnetic Stray Fields	768
	J. Mertens, J. Bauche, M.A. Fraser, B. Goddard, R. Ostojić, J.S. Schmidt CERN, Geneva, Switzerland
	The ISOLDE facility at CERN produces radioactive isotopes far from stability for fundamental nuclear physics research. The radioactive beams are accelerated to high-energy using a post-accelerator before being transferred for study in different experiments at the end of a network of High Energy Beam Transfer (HEBT) lines. In the framework of the HIE-ISOLDE project, the energy of post-accelerated beams is to be increased to over 10 MeV/u and new experimental detectors are being proposed for installation to exploit the new energy regime. The stray magnetic fields associated with many of the new detectors will distort the beam trajectories in the HEBT, potentially affecting the transmission of the low intensity beams delivered to the experiments. In this contribution, the influence on the HEBT of the stray field of the proposed ISOL Solenoidal Spectrometer is discussed, correction schemes described and shielding options assessed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPIK102
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEOAA2	Status of Radioactive Ion Beam Post-Acceleration at CERN-ISOLDE	2466
	Y. Kadi, W. Andreazza, J. Bauche, A. Behrens, A.P. Bernardes, J.A. Ferreira Somoza, F. Formenti, M.A. Fraser, M.J. Garcia Borge, N. Guillotin, K. Johnston, G. Kautzmann, Y. Leclercq, M. Martino, A. Miyazaki, R. Mompo, A. Papageorgiou Koufidou, O. Pirotte, J.A. Rodriguez, S. Sadovich, E. Siesling, M. Therasse, D. Valuch, W. Venturini Delsolaro CERN, Geneva, Switzerland
	Funding: We acknowledge funding from the Belgian Big Science program of the FWO (Research Foundation Flanders) and the Research Council K.U. Leuven. The HIE-ISOLDE project* (High Intensity and Energy ISOLDE) reached an important milestone in September 2016 when the first physics run was carried out with radioactive beams at 6 MV/m. This is the first stage in the upgrade of the REX post-accelerator, whereby the energy of the radioactive ion beams was increased from 3 to 5.5 MeV per nucleon. The facility will ultimately be equipped with four high-beta cryomodule that will accelerate the beams up to 10 MeV per nucleon for the heaviest isotopes available at ISOLDE. The first 2 cryomodules of the new linac, hosting each five superconducting cavities and one solenoid, were commissioned in August 2016. Besides demonstrating the experimental capabilities of the facility, this successful first run validated the technical choices of the HIE ISOLDE team and provided a fitting reward for eight years of rigorous R&D efforts. At the start of 2018, HIE-ISOLDE is expected to complete the energy upgrade, reaching 10 MeV/u and becoming an attractive facility for a wide variety of experiments. This contribution will focus on the results of the commissioning and on the main technical issues that were highlighted. * M.J.G. Borge and K. Riisager (2016), HIE-ISOLDE, the project and the physics opportunities, European Physical Journal A 52: 334, DOI: 10.1140/epja/i2016-16334-4
	Slides WEOAA2 [7.659 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEOAA2
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPAB146	Investigation of the Remanent Field of the SPS Main Dipoles and Possible Solutions for Machine Operation	4069
	F.M. Velotti, H. Bartosik, J. Bauche, M.C.L. Buzio, K. Cornelis, M.A. Fraser, V. Kain CERN, Geneva, Switzerland
	The CERN Super Proton Synchrotron (SPS) provides different types of beams at different extraction energies. The main magnets of the SPS are regulated with a current loop, but it has turned out that hysteresis effects from the main dipoles have a significant impact on reproducibility and hence efficiency and availability. Beam and machine parameters were found to depend on the programmed sequence of magnetic cycles - the so-called super cycle - representing the production of the different beams. The scientific program of the SPS requires frequent changes of the supercycle composition and the effect of the main magnet hysteresis has to be understood, modelled and used in accelerator control system. This paper summarises the first main field measurements carried out with the currently available systems during operational conditions as well as measurements of vital machine and beam parameters as a function of the super cycle composition. Finally, ideas will be presented to provide reproducibility by automatically correcting different parameters taking the magnetic history of the main magnets into account.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPAB146
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

SPS Slow Extracted Spill Quality During the 2016 Run

627

V. Kain, J. Bauche, P. Catherine, K. Cornelis, M.A. Fraser, L. Gatignon, C.M. Genton, B. Goddard, K. Kahle, M. Magrans de Abril, O. Michels, L.S. Stoel, F.M. Velotti
CERN, Geneva, Switzerland

The flux of particles slow extracted with the 1/3 integer resonance from the Super Proton Synchrotron at CERN should ideally be constant over the length of the extraction plateau, for optimum use of the beam by the fixed target experiments. The extracted intensity is controlled in feed-forward correction of the horizontal tune via the main SPS quadrupoles. The Mains power supply noise at 50 Hz and harmonics is also corrected in feed-forward by small amplitude tune modulation at the respective frequencies with a dedicated additional quadrupole circuit. In 2016 the spill quality could be much improved with respect to the situation of the previous year with more performant algorithms. In this paper the improved tools are described and the characteristics of the SPS slow extracted spill in terms of macro structure and typical frequency content are shown. Other sources of perturbation were, however, also present in 2016 which frequently caused the spill quality to be much reduced. The different effects are discussed and possible or actual solutions detailed. Finally, the evolution of the spill quality during characteristic periods in the 2016 run is presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPIK049

Export •

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

MOPIK102

Beam Dynamics Studies of the HIE-ISOLDE Transfer Lines in the Presence of Magnetic Stray Fields

768

J. Mertens, J. Bauche, M.A. Fraser, B. Goddard, R. Ostojić, J.S. Schmidt
CERN, Geneva, Switzerland

The ISOLDE facility at CERN produces radioactive isotopes far from stability for fundamental nuclear physics research. The radioactive beams are accelerated to high-energy using a post-accelerator before being transferred for study in different experiments at the end of a network of High Energy Beam Transfer (HEBT) lines. In the framework of the HIE-ISOLDE project, the energy of post-accelerated beams is to be increased to over 10 MeV/u and new experimental detectors are being proposed for installation to exploit the new energy regime. The stray magnetic fields associated with many of the new detectors will distort the beam trajectories in the HEBT, potentially affecting the transmission of the low intensity beams delivered to the experiments. In this contribution, the influence on the HEBT of the stray field of the proposed ISOL Solenoidal Spectrometer is discussed, correction schemes described and shielding options assessed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPIK102

Export •

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

WEOAA2

Status of Radioactive Ion Beam Post-Acceleration at CERN-ISOLDE

2466

Y. Kadi, W. Andreazza, J. Bauche, A. Behrens, A.P. Bernardes, J.A. Ferreira Somoza, F. Formenti, M.A. Fraser, M.J. Garcia Borge, N. Guillotin, K. Johnston, G. Kautzmann, Y. Leclercq, M. Martino, A. Miyazaki, R. Mompo, A. Papageorgiou Koufidou, O. Pirotte, J.A. Rodriguez, S. Sadovich, E. Siesling, M. Therasse, D. Valuch, W. Venturini Delsolaro
CERN, Geneva, Switzerland

Funding: We acknowledge funding from the Belgian Big Science program of the FWO (Research Foundation Flanders) and the Research Council K.U. Leuven.
The HIE-ISOLDE project* (High Intensity and Energy ISOLDE) reached an important milestone in September 2016 when the first physics run was carried out with radioactive beams at 6 MV/m. This is the first stage in the upgrade of the REX post-accelerator, whereby the energy of the radioactive ion beams was increased from 3 to 5.5 MeV per nucleon. The facility will ultimately be equipped with four high-beta cryomodule that will accelerate the beams up to 10 MeV per nucleon for the heaviest isotopes available at ISOLDE. The first 2 cryomodules of the new linac, hosting each five superconducting cavities and one solenoid, were commissioned in August 2016. Besides demonstrating the experimental capabilities of the facility, this successful first run validated the technical choices of the HIE ISOLDE team and provided a fitting reward for eight years of rigorous R&D efforts. At the start of 2018, HIE-ISOLDE is expected to complete the energy upgrade, reaching 10 MeV/u and becoming an attractive facility for a wide variety of experiments. This contribution will focus on the results of the commissioning and on the main technical issues that were highlighted.
* M.J.G. Borge and K. Riisager (2016), HIE-ISOLDE, the project and the physics opportunities, European Physical Journal A 52: 334, DOI: 10.1140/epja/i2016-16334-4

Slides WEOAA2 [7.659 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEOAA2

Export •

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

THPAB146

Investigation of the Remanent Field of the SPS Main Dipoles and Possible Solutions for Machine Operation

4069

F.M. Velotti, H. Bartosik, J. Bauche, M.C.L. Buzio, K. Cornelis, M.A. Fraser, V. Kain
CERN, Geneva, Switzerland

The CERN Super Proton Synchrotron (SPS) provides different types of beams at different extraction energies. The main magnets of the SPS are regulated with a current loop, but it has turned out that hysteresis effects from the main dipoles have a significant impact on reproducibility and hence efficiency and availability. Beam and machine parameters were found to depend on the programmed sequence of magnetic cycles - the so-called super cycle - representing the production of the different beams. The scientific program of the SPS requires frequent changes of the supercycle composition and the effect of the main magnet hysteresis has to be understood, modelled and used in accelerator control system. This paper summarises the first main field measurements carried out with the currently available systems during operational conditions as well as measurements of vital machine and beam parameters as a function of the super cycle composition. Finally, ideas will be presented to provide reproducibility by automatically correcting different parameters taking the magnetic history of the main magnets into account.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPAB146

Export •

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