IPAC2011 - List of Authors (Lebasque, P.)

Paper	Title	Page
TUPC068	SOLEIL Beam Orbit Stability Improvements	1156
	N. Hubert, Y.-M. Abiven, F. Blache, F. Briquez, L. Cassinari, J.-C. Denard, J.-F. Lamarre, P. Lebasque, N. Leclercq, A. Lestrade, L.S. Nadolski SOLEIL, Gif-sur-Yvette, France
	The electron beam orbit stability has been significantly improved at synchrotron SOLEIL. Low frequency noise sources have been localized and identified: the fans installed on the storage ring to cool down the ceramic chambers of the kickers, shaker and FCT, were slightly wobbling the electron beam orbit at 46, 50, 54 and 10⁸ Hz. The localization method and the solutions that will allow reducing the noise from 0.8 μm RMS down to 0.3 μm are presented. Besides, a new 160 m long beamline, NANOSCOPIUM, is being installed on a canted straight section. Its photon beam position stability requirements are very tight calling for the following improvements: addition of 2 more BPMs and fast correctors in the orbit feedback loops, new INVAR stands for BPM and XBPM integrating Hydrostatic Level System sensors. The paper is also discussing other projects that did or will contribute to improving the beam orbit stability: installation of 145 temperature sensors on the storage ring, a new analog feedforward correction system for insertion devices, and the use of the bending magnet X-BPM measurements in the slow and fast orbit feedback loops.

THPC005	First Measurements with a Kicked Off Axis Bunch for Pseudo Single Bunch Mode Studies at SOLEIL	2912
	L.S. Nadolski, J.-P. Lavieville, P. Lebasque, A. Nadji, J.P. Ricaud, M.G. Silly, F. Sirotti SOLEIL, Gif-sur-Yvette, France
	At SOLEIL, the time resolved French community benefits of single bunch operation few weeks a year. Meanwhile most of the multi-bunch filling pattern based experiments are not possible due to the low photon flux. Following the pioneer work performed at ALS, a new operation mode is under study at SOLEIL where the storage ring is filled up with a special hybrid mode: ¾ multibunch filling pattern and a single bunch with higher current in the last ¼. The so-called pseudo single bunch-filling pattern is obtained if the closed orbit of the single bunch is not the same as the one of the other bunches. Preliminary results are presented where the pinger magnet time impulse response has been significantly reduced while its frequency was increased from 3 Hz up to 1 kHz. This magnet is used as an additional corrector magnet to change only the single bunch closed orbit. First experimental results observed at one interested beamline are also discussed. S. Kwiatkowski et al., “'CAMSHAFT' Bunch Kicker Design for the ALS Storage Ring", Proc. of EPAC2006, THPLS114, p. 3547, (2006).

THPC044	Operation and Performance Upgrade of the Soleil Storage Ring	3002
	A. Nadji, P. Brunelle, M.-E. Couprie, J.-C. Denard, J.-M. Filhol, J.-F. Lamarre, P. Lebasque, A. Loulergue, P. Marchand, L.S. Nadolski, R. Nagaoka, M.-A. Tordeux SOLEIL, Gif-sur-Yvette, France
	SOLEIL delivers photons to 24 beamlines. Up to 22 very diverse insertion devices (IDs) are now installed on the storage ring, and 4 more will come by summer 2011, including a Cryogenic undulator and an electromagnetic/permanent magnet helical undulator, both designed and built at SOLEIL. Work is continuing on beam dynamics and magnetic corrections to reduce the nonlinear effects of all these IDs. A new optics incorporating an additional quadrupole triplet in one long straight section has been successfully tested and will be put in operation by fall 2011. A new coupling correction will also be implemented to maintain the ratio of the vertical to the horizontal emittances at 1% for any IDs configuration. The electron beam orbit stability has been significantly improved reaching a residual noise of 300 nm RMS. Photon LIBERA modules of X-BPM located on the bends, will be integrated soon in the orbit feedback loops. 4905 hours have been delivered in 2010 to the beamlines with an availability of 96.3%. The user operation with the maximum current of 500 mA is foreseen to start by fall 2011, after the completion of the radiation safety tests of the beamlines.

THPC140	Design, Tuning and Results of the Pulsed Magnetic Systems for the Beam Injection in the SOLEIL Storage Ring Operated in ‘Transparent’ Top Up Mode	3215
	P. Lebasque, R. Ben El Fekih, M. Bol, J. Da Silva Castro, A. Hardy, C. Herbeaux, J.-P. Lavieville, A. Loulergue, J.L. Marlats, D. Muller, G. Renaud, J.P. Ricaud SOLEIL, Gif-sur-Yvette, France
	From the beginning, the SOLEIL Storage Ring was designed to operate in Top Up injection mode. So all equipments involved have been specified to generate as small as possible beam perturbations of the stored beam during the electron beam injection. This concerns many aspects of the design and realization of the injection pulsed magnets (kickers and septa), their vacuum chambers, pulsed power supplies and timing electronics. Despite quite satisfactory results of pulsed magnetic measurements in labs, a still too large perturbation was observed on the e^- beam orbit during the Storage Ring commissioning. Therefore a strong work of systematic measurements, analysis of each phenomena, tuning or modification of each device was led until reaching rather good and acceptable performances. This paper will present the results obtained. At this stage, the Storage Ring beam orbit is sufficiently stable in Top Up injection mode so that it is almost transparent to the 24 beam lines, even for the most sensitive ones. After a summary of the main significant topics, we present the developments foreseen to further improve the performances and make a new step towards a “perfect” Top Up injection.

THPC151	The 65 mm Period Electromagnetic/Permanent Magnets Helical Undulator at SOLEIL	3239
	F. Marteau, P. Berteaud, F. Bouvet, L. Chapuis, M.-E. Couprie, J.P. Daguerre, T.K. El Ajjouri, J.-M. Filhol, P. Lebasque, J.L. Marlats, A. Mary, K. Tavakoli SOLEIL, Gif-sur-Yvette, France
	SOLEIL prepares a new 65 mm period Electromagnetic/Permanent Magnets Helical Undulator (EMPHU), with a rapid switching at 5 Hz of the polarization required for dichroïsm experiments. The vertical field Bz is produced by coils fed by a fast switching power supply (designed and built in house), with a maximum current of 350 A and a polarity switching time shorter than 100 ms. The coils consist of 25 stacked copper layers shaped by water jet cutting. The current flows in 16 layers and 9 of them are cooled with thermal drain to a water piping. 4 additional power supplies feed 2 types of correction coils for the dynamic compensation of the field integrals, besides the ones for the termination. 1.28 T remanence NdFeB permanent magnets generate the horizontal field Bx. Peak Bz and Bx in the helical configuration reach 0.24 T at 14.7 mm minimum gap. Thermal modelling and measurements aim at keeping the magnet temperature constant. The static magnetic configuration was optimised using the ID_Builder software and the trajectory were checked for insuring a good reproducibility of the photon beam pointing when sweeping from one helicity to the other.

Paper

Title

Page

SOLEIL Beam Orbit Stability Improvements

1156

N. Hubert, Y.-M. Abiven, F. Blache, F. Briquez, L. Cassinari, J.-C. Denard, J.-F. Lamarre, P. Lebasque, N. Leclercq, A. Lestrade, L.S. Nadolski
SOLEIL, Gif-sur-Yvette, France

The electron beam orbit stability has been significantly improved at synchrotron SOLEIL. Low frequency noise sources have been localized and identified: the fans installed on the storage ring to cool down the ceramic chambers of the kickers, shaker and FCT, were slightly wobbling the electron beam orbit at 46, 50, 54 and 10⁸ Hz. The localization method and the solutions that will allow reducing the noise from 0.8 μm RMS down to 0.3 μm are presented. Besides, a new 160 m long beamline, NANOSCOPIUM, is being installed on a canted straight section. Its photon beam position stability requirements are very tight calling for the following improvements: addition of 2 more BPMs and fast correctors in the orbit feedback loops, new INVAR stands for BPM and XBPM integrating Hydrostatic Level System sensors. The paper is also discussing other projects that did or will contribute to improving the beam orbit stability: installation of 145 temperature sensors on the storage ring, a new analog feedforward correction system for insertion devices, and the use of the bending magnet X-BPM measurements in the slow and fast orbit feedback loops.

THPC005

First Measurements with a Kicked Off Axis Bunch for Pseudo Single Bunch Mode Studies at SOLEIL

2912

L.S. Nadolski, J.-P. Lavieville, P. Lebasque, A. Nadji, J.P. Ricaud, M.G. Silly, F. Sirotti
SOLEIL, Gif-sur-Yvette, France

At SOLEIL, the time resolved French community benefits of single bunch operation few weeks a year. Meanwhile most of the multi-bunch filling pattern based experiments are not possible due to the low photon flux. Following the pioneer work performed at ALS*, a new operation mode is under study at SOLEIL where the storage ring is filled up with a special hybrid mode: ¾ multibunch filling pattern and a single bunch with higher current in the last ¼. The so-called pseudo single bunch-filling pattern is obtained if the closed orbit of the single bunch is not the same as the one of the other bunches. Preliminary results are presented where the pinger magnet time impulse response has been significantly reduced while its frequency was increased from 3 Hz up to 1 kHz. This magnet is used as an additional corrector magnet to change only the single bunch closed orbit. First experimental results observed at one interested beamline are also discussed.
* S. Kwiatkowski et al., “'CAMSHAFT' Bunch Kicker Design for the ALS Storage Ring", Proc. of EPAC2006, THPLS114, p. 3547, (2006).

THPC044

Operation and Performance Upgrade of the Soleil Storage Ring

3002

A. Nadji, P. Brunelle, M.-E. Couprie, J.-C. Denard, J.-M. Filhol, J.-F. Lamarre, P. Lebasque, A. Loulergue, P. Marchand, L.S. Nadolski, R. Nagaoka, M.-A. Tordeux
SOLEIL, Gif-sur-Yvette, France

SOLEIL delivers photons to 24 beamlines. Up to 22 very diverse insertion devices (IDs) are now installed on the storage ring, and 4 more will come by summer 2011, including a Cryogenic undulator and an electromagnetic/permanent magnet helical undulator, both designed and built at SOLEIL. Work is continuing on beam dynamics and magnetic corrections to reduce the nonlinear effects of all these IDs. A new optics incorporating an additional quadrupole triplet in one long straight section has been successfully tested and will be put in operation by fall 2011. A new coupling correction will also be implemented to maintain the ratio of the vertical to the horizontal emittances at 1% for any IDs configuration. The electron beam orbit stability has been significantly improved reaching a residual noise of 300 nm RMS. Photon LIBERA modules of X-BPM located on the bends, will be integrated soon in the orbit feedback loops. 4905 hours have been delivered in 2010 to the beamlines with an availability of 96.3%. The user operation with the maximum current of 500 mA is foreseen to start by fall 2011, after the completion of the radiation safety tests of the beamlines.

THPC140

Design, Tuning and Results of the Pulsed Magnetic Systems for the Beam Injection in the SOLEIL Storage Ring Operated in ‘Transparent’ Top Up Mode

3215

P. Lebasque, R. Ben El Fekih, M. Bol, J. Da Silva Castro, A. Hardy, C. Herbeaux, J.-P. Lavieville, A. Loulergue, J.L. Marlats, D. Muller, G. Renaud, J.P. Ricaud
SOLEIL, Gif-sur-Yvette, France

From the beginning, the SOLEIL Storage Ring was designed to operate in Top Up injection mode. So all equipments involved have been specified to generate as small as possible beam perturbations of the stored beam during the electron beam injection. This concerns many aspects of the design and realization of the injection pulsed magnets (kickers and septa), their vacuum chambers, pulsed power supplies and timing electronics. Despite quite satisfactory results of pulsed magnetic measurements in labs, a still too large perturbation was observed on the e^- beam orbit during the Storage Ring commissioning. Therefore a strong work of systematic measurements, analysis of each phenomena, tuning or modification of each device was led until reaching rather good and acceptable performances. This paper will present the results obtained. At this stage, the Storage Ring beam orbit is sufficiently stable in Top Up injection mode so that it is almost transparent to the 24 beam lines, even for the most sensitive ones. After a summary of the main significant topics, we present the developments foreseen to further improve the performances and make a new step towards a “perfect” Top Up injection.

THPC151

The 65 mm Period Electromagnetic/Permanent Magnets Helical Undulator at SOLEIL

3239

F. Marteau, P. Berteaud, F. Bouvet, L. Chapuis, M.-E. Couprie, J.P. Daguerre, T.K. El Ajjouri, J.-M. Filhol, P. Lebasque, J.L. Marlats, A. Mary, K. Tavakoli
SOLEIL, Gif-sur-Yvette, France

SOLEIL prepares a new 65 mm period Electromagnetic/Permanent Magnets Helical Undulator (EMPHU), with a rapid switching at 5 Hz of the polarization required for dichroïsm experiments. The vertical field Bz is produced by coils fed by a fast switching power supply (designed and built in house), with a maximum current of 350 A and a polarity switching time shorter than 100 ms. The coils consist of 25 stacked copper layers shaped by water jet cutting. The current flows in 16 layers and 9 of them are cooled with thermal drain to a water piping. 4 additional power supplies feed 2 types of correction coils for the dynamic compensation of the field integrals, besides the ones for the termination. 1.28 T remanence NdFeB permanent magnets generate the horizontal field Bx. Peak Bz and Bx in the helical configuration reach 0.24 T at 14.7 mm minimum gap. Thermal modelling and measurements aim at keeping the magnet temperature constant. The static magnetic configuration was optimised using the ID_Builder software and the trajectory were checked for insuring a good reproducibility of the photon beam pointing when sweeping from one helicity to the other.