IBIC2013 - List of Keywords (ESRF)

Paper	Title	Other Keywords	Page
WEPC13	Optimisation of the SVD Treatment in the Fast Orbit Correction of the ESRF Storage Ring	BPM, feedback, storage-ring, injection	694
	E. Plouviez, F. Epaud, L. Farvacque, J.M. Koch ESRF, Grenoble, France
	The ESRF fast orbit correction system has been in operation since May 2012. The orbit correction scheme relies classically on the calculation of a correction orbit based on the SVD analysis of the response matrix of our 224 BPMs to each of our 96 correctors. The rate of the calculation of the corrections is 10 KHz; we use a PI loop achieving a bandwidth of 150Hz completed with a narrow band pass filter with extra gain at 50Hz. In order to make the best use of the correctors dynamic range and of the resolution of the calculation, it can be useful to limit the bandwidth of loop for the highest order vectors of the SVD, or even to totally remove some of these vectors from the correction down to DC. Removing some of the eigen vectors while avoiding that the loop becomes unstable usually increases a lot the complexity of the matrix calculations: we have developed an algorithm which overcomes this problem; The test of this algorithm is presented. We present also the beneficial effect at high frequency of the limitation of the gain of the correction of the highest SVD eigen vectors on the demand of the peak strength of the correctors and on the resolution of the correction calculation.
	Poster WEPC13 [0.974 MB]

WEPC18	Development of Compact Electronics Dedicated to Beam Position Monitors in Injectors and Boosters	booster, beam-position, BPM, controls	713
	G. Jug, M. Cargnelutti I-Tech, Solkan, Slovenia K.B. Scheidt ESRF, Grenoble, France
	The need for state-of-the-art electronics for data-acquisition and processing of BPM signals in Injector and/or Booster Synchrotrons is being addressed in a development that aims at making such system available with less complexity and yet fulfilling precisely the needs of such specific BPMs. The ESRF Booster Synchrotron uses 75 BPMs in its 300m circumference to measure the orbit along its acceleration cycle of 50 milliseconds for the electron beam from 0.2 to 6GeV. The 25 year old electronics of these BPMs are in need of replacement. While BPM developments in recent years have focused on devices for Storage Rings that face extreme requirements like sub-micron drift with time, beam intensity, etc. that result in complicated implementation schemes. This new development combines both the simplification in the measurement concept and the implementation of novelties like compact design integrating RF electronics, with power-over-Ethernet supply and passive cooling, a powerful System-on-Chip engine and easy communication via SCPI commands. This paper will present the full design concept and its aimed functionalities as a BPM device that should offer an excellent price/performance ratio.

WEPC22	First Steps Towards a Fast Orbit Feedback at ALBA	feedback, DIAMOND, brilliance, simulation	727
	A. Olmos, S. Blanch-Torné, Z. Martí, J. Moldes, M. Muñoz, R. Petrocelli, X. Serra-Gallifa CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain A. Gutierrez-Milla UAB, Barcelona, Spain
	An optimum performance of the ALBA facility requires a beam orbit stability on the sub-micron level up to frequencies in the 100 Hz range. The Fast Orbit FeedBack system (FOFB) is designed to achieve such a stability. After investigation of possible system architecture, a decision has been taken that exploits the available in-house hardware. This “low-cost” first stage FOFB will be an ideal test-bench to learn about beam stabilization and find possible problems and improvements on it. This report explains the current lay-out and status of the FOFB at ALBA.
	Poster WEPC22 [3.107 MB]

WEPC33	Upgrade of Beam Phase Monitors for the ESRF Injector and Storage Ring	storage-ring, booster, injection, BPM	757
	K.B. Scheidt, B. Joly ESRF, Grenoble, France
	The measurement of the phase relation between the stored beam in the Storage Ring and the beam circulating in the Booster Synchrotron is now done with high precision and at high speed using a single unit of commercial BPM electronics. The quadrature demodulation, driven by a common PLL, done in these digital electronics on each of its four RF input channels makes the relative measurement of the I/Q components, hence phase relation, easy and strait forward. The RF signals of the relatively low current Booster come from two stripline outputs while that of the Storage Ring from two small BPM buttons. Treating simultaneously four signals, thus with a redundancy of two to measure the phase between two sources, allows to perform intrinsic shot-to-shot cross verifications on resolution and reproducibility. The long-term stability of this device has also been successfully assessed by independent verifications against time and temperature drifts. An identical unit has now been added for phase measurements between the Storage Ring beam and the RF cavity signals. Results with beam and assessment of its scope of performance will be presented on both systems.
	Poster WEPC33 [0.836 MB]

WEPF12	Characterisation of Al-Compound Refractive Lenses for X-Rays	LEFT, photon, emittance, dipole	837
	F. Ewald, J.C. Biasci ESRF, Grenoble, France
	We report on measurements of the surface quality (shape) of aluminium compound refractive lenses using a thin collimated X-ray beam from one of our bending magnet diagnostics beam ports. Two types of lenses were tested for overall radius of curvature, surface quality and thickness: commercially available lenses (RWTH Aachen), and lenses of the same type manufactured at the ESRF. The different surface qualities can be readily discerned with our relatively simple setup. While the technique should be improved for more precise results, it already shows clearly the imperfect surface structure of the ESRF lenses. The image quality of the beam, however, is not affected to a visible extent in our emittance measurement setup at vertical emittances of typically ~ 6 pm.

Paper

Title

Other Keywords

Page

WEPC13

Optimisation of the SVD Treatment in the Fast Orbit Correction of the ESRF Storage Ring

BPM, feedback, storage-ring, injection

694

E. Plouviez, F. Epaud, L. Farvacque, J.M. Koch
ESRF, Grenoble, France

The ESRF fast orbit correction system has been in operation since May 2012. The orbit correction scheme relies classically on the calculation of a correction orbit based on the SVD analysis of the response matrix of our 224 BPMs to each of our 96 correctors. The rate of the calculation of the corrections is 10 KHz; we use a PI loop achieving a bandwidth of 150Hz completed with a narrow band pass filter with extra gain at 50Hz. In order to make the best use of the correctors dynamic range and of the resolution of the calculation, it can be useful to limit the bandwidth of loop for the highest order vectors of the SVD, or even to totally remove some of these vectors from the correction down to DC. Removing some of the eigen vectors while avoiding that the loop becomes unstable usually increases a lot the complexity of the matrix calculations: we have developed an algorithm which overcomes this problem; The test of this algorithm is presented. We present also the beneficial effect at high frequency of the limitation of the gain of the correction of the highest SVD eigen vectors on the demand of the peak strength of the correctors and on the resolution of the correction calculation.

Poster WEPC13 [0.974 MB]

WEPC18

Development of Compact Electronics Dedicated to Beam Position Monitors in Injectors and Boosters

booster, beam-position, BPM, controls

713

G. Jug, M. Cargnelutti
I-Tech, Solkan, Slovenia
K.B. Scheidt
ESRF, Grenoble, France

The need for state-of-the-art electronics for data-acquisition and processing of BPM signals in Injector and/or Booster Synchrotrons is being addressed in a development that aims at making such system available with less complexity and yet fulfilling precisely the needs of such specific BPMs. The ESRF Booster Synchrotron uses 75 BPMs in its 300m circumference to measure the orbit along its acceleration cycle of 50 milliseconds for the electron beam from 0.2 to 6GeV. The 25 year old electronics of these BPMs are in need of replacement. While BPM developments in recent years have focused on devices for Storage Rings that face extreme requirements like sub-micron drift with time, beam intensity, etc. that result in complicated implementation schemes. This new development combines both the simplification in the measurement concept and the implementation of novelties like compact design integrating RF electronics, with power-over-Ethernet supply and passive cooling, a powerful System-on-Chip engine and easy communication via SCPI commands. This paper will present the full design concept and its aimed functionalities as a BPM device that should offer an excellent price/performance ratio.

WEPC22

First Steps Towards a Fast Orbit Feedback at ALBA

feedback, DIAMOND, brilliance, simulation

727

A. Olmos, S. Blanch-Torné, Z. Martí, J. Moldes, M. Muñoz, R. Petrocelli, X. Serra-Gallifa
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
A. Gutierrez-Milla
UAB, Barcelona, Spain

An optimum performance of the ALBA facility requires a beam orbit stability on the sub-micron level up to frequencies in the 100 Hz range. The Fast Orbit FeedBack system (FOFB) is designed to achieve such a stability. After investigation of possible system architecture, a decision has been taken that exploits the available in-house hardware. This “low-cost” first stage FOFB will be an ideal test-bench to learn about beam stabilization and find possible problems and improvements on it. This report explains the current lay-out and status of the FOFB at ALBA.

Poster WEPC22 [3.107 MB]

WEPC33

Upgrade of Beam Phase Monitors for the ESRF Injector and Storage Ring

storage-ring, booster, injection, BPM

757

K.B. Scheidt, B. Joly
ESRF, Grenoble, France

The measurement of the phase relation between the stored beam in the Storage Ring and the beam circulating in the Booster Synchrotron is now done with high precision and at high speed using a single unit of commercial BPM electronics. The quadrature demodulation, driven by a common PLL, done in these digital electronics on each of its four RF input channels makes the relative measurement of the I/Q components, hence phase relation, easy and strait forward. The RF signals of the relatively low current Booster come from two stripline outputs while that of the Storage Ring from two small BPM buttons. Treating simultaneously four signals, thus with a redundancy of two to measure the phase between two sources, allows to perform intrinsic shot-to-shot cross verifications on resolution and reproducibility. The long-term stability of this device has also been successfully assessed by independent verifications against time and temperature drifts. An identical unit has now been added for phase measurements between the Storage Ring beam and the RF cavity signals. Results with beam and assessment of its scope of performance will be presented on both systems.

Poster WEPC33 [0.836 MB]

WEPF12

Characterisation of Al-Compound Refractive Lenses for X-Rays

LEFT, photon, emittance, dipole

837

F. Ewald, J.C. Biasci
ESRF, Grenoble, France

We report on measurements of the surface quality (shape) of aluminium compound refractive lenses using a thin collimated X-ray beam from one of our bending magnet diagnostics beam ports. Two types of lenses were tested for overall radius of curvature, surface quality and thickness: commercially available lenses (RWTH Aachen), and lenses of the same type manufactured at the ESRF. The different surface qualities can be readily discerned with our relatively simple setup. While the technique should be improved for more precise results, it already shows clearly the imperfect surface structure of the ESRF lenses. The image quality of the beam, however, is not affected to a visible extent in our emittance measurement setup at vertical emittances of typically ~ 6 pm.