IBIC2013 - List of Keywords (optics)

Paper	Title	Other Keywords	Page
MOPC34	Longitudinal Beam Profile Monitor for Investigating the Microbunching Instability at Diamond Light Source	DIAMOND, radiation, longitudinal, storage-ring	143
	W. Shields, R. Bartolini, A.F.D. Morgan, G. Rehm Diamond, Oxfordshire, United Kingdom R. Bartolini, P. Karataev JAI, Oxford, United Kingdom P. Karataev Royal Holloway, University of London, Surrey, United Kingdom
	An investigation into the microbunching instability at Diamond Light Source has recently been conducted. Beyond the instability threshold, the bunch emits bursts of coherent synchrotron radiation with wavelengths comparable to the bunch length or shorter. The operating conditions for producing the instability include both normal optics, and low-alpha optics, where the bunch length can be shortened to a few picoseconds. A Michelson interferometer has been designed and installed utilising a silicon crystal wafer beamsplitter. Large bandwidth, room temperature pyroelectric detectors and low-noise, fast-response Schottky Barrier diode detectors have been employed to generate interferograms. In this paper, we describe the observed spectral content and the resulting calculated bunch length.

MOPF05	Operating Semiconductor Timepix Detector with Optical Readout in an Extremely Hostile Environment of Laser Plasma Acceleration Experiment	laser, vacuum, target, shielding	208
	L. Pribyl Czech Republic Academy of Sciences, Institute of Physics, Prague, Czech Republic
	The laser plasma acceleration (LPA) experiments produce very intensive electromagnetic pulses (EMP) complicating operation of sensitive electronic detectors. We present our experience with new optical readout and EMP shielding for hybrid silicon pixel detector Timepix, which enabled its operation in an extremely hostile electromagnetic LPA environment. The Timepix detector provides a matrix of 256x256 spectroscopic channels with 55 μm pitch. An optical readout, battery powering and shielding against electromagnetic pulses (EMP) have been developed as part of the ELI Beamlines/IEAP project for the detector Timepix and it significantly improved its resistance to EMP with respect to previous setup using metallic cables for both data acquisition and powering. The new optical setup was successfully tested under vacuum at Prague Asterix Laser System (PALS) during experiments with laser pulses of energies up to 700 J and duration of 350 ps bombarding thin foil solid target. Electromagnetic field was measured both outside the vacuum chamber and inside. The recorded spectrometric data were analyzed and interpreted in a context of an independent experimental campaign run in parallel. X. Llopart et al.: Timepix, a 65k Programmable Pixel Readout Chip for Arrival Time, Energy and/or Photon Counting Measurements, Nucl. Instr. and Meth. in Phys. Res. A. Vol. 581 (2007), p485

MOPF06	Beam Profile Monitors at REGAE	electron, diagnostics, photon, SNR	212
	H. Delsim-Hashemi, K. Flöttmann DESY, Hamburg, Germany S. Bayesteh Uni HH, Hamburg, Germany
	A new linac is commissioned at DESY mainly as the electron source for femtosecond electron diffraction facility REGAE (Relativistic Electron Gun for Atomic Exploration). REGAE enables studies on structural dynamics of atomic transition states occurring in the sub-hundred femtosecond time-scale. REGAE comprises a photo-cathode gun followed by normal conducting 1.5 cell rf-cavity to provide sub pC electron-bunches of 2-5 MeV with a coherence length of 30nm. In order to produce and maintain such electron bunches, sophisticated single-shot diagnostics are desired e.g. emittance, energy, energy-spread and bunch-length measurement. REGAE rep-rate can be up to 50 Hz. This relatively high rep-rate makes it more challenging to deal with low intensity detection especially in single-shot mode. In this contribution the conceptual ideas, realization and results of transversal diagnostics will be presented.

MOPF07	Turn by Turn Profile Monitors for the CERN SPS and LHC	LHC, OTR, SPS, proton	216
	S. Burger, A. Boccardi, E. Bravin, A. Goldblatt, A. Ravni, F. Roncarolo, R.S. Sautier CERN, Geneva, Switzerland
	In order to preserve the transverse beam emittance along the acceleration chain it is important that the optics of the transfer lines is perfectly matched to the optics of the rings. Special monitors capable of measuring the beam profiles with a turn by turn resolution are very helpful in this respect. A new type of matching monitor has been developed at CERN for the SPS and LHC machines. This monitor relies on imaging OTR light by mean of a fast line scan CMOS and an asymmetric optical system based on cylindrical lenses. This contribution describes the design of this monitor, presents the results obtained during the 2012-13 run and outlines the plans for further improving the design.

MOPF08	Design and Performance of the Upgraded LHC Synchrotron Light Monitor	LHC, focusing, undulator, dipole	220
	A. Goldblatt, E. Bravin, F. Roncarolo, G. Trad CERN, Geneva, Switzerland
	The LHC is equipped with two synchrotron radiation systems, one per beam, used to measure the transverse bunch distributions. The light emitted by a superconducting undulator and/or by a dipole magnet (depending on beam energy) is intercepted by an extraction mirror in vacuum and sent through a viewport to the imaging Beam Synchrotron Radiation Telescope (BSRT). The first version of the telescope, used from 2009 to mid 2012, was based on spherical focusing mirrors in order to minimize chromatic aberrations. However, this required a very complicated delay line in order to switch the focus between the two different light sources as a function of beam energy. A new system based on optical lenses was designed and installed in mid 2012 in order to simplify the optical line and thus reduce misalignment and focusing errors. The first results with LHC beam using this new system showed a significant reduction in the correction factor required to match the emittance as measured by wire scanners. This contribution discusses the performance of the new optical system, presenting the LHC results and comparing simulations with measurement performed in the laboratory using a BSRT replica.

MOPF28	Optics Non-Linear Components Measurement Using BPM Signals	focusing, BPM, beam-losses, synchrotron	279
	M. Alhumaidi, A.M. Zoubir TU Darmstadt, Darmstadt, Germany
	The knowledge of linear and non-linear errors in circular accelerator optics is very crucial for controlling and compensating resonances and their consequent beam losses. This is indispensable, especially for high intensity machines. Fortunately, the relationship between the recorded beam offset signals at the BPMs is a manifestation of the accelerator optics, and can therefore be exploited in the determination of the optics linear and non-linear components. We propose a novel method for estimating lattice non-linear components located in-between the positions of two BPMs by analyzing the beam offset signals of a BPMs triple containing these two BPMs. Depending on the non-linear components in-between the locations of the BPMs triple, the relationship between the beam offsets follows a multivariate polynomial. After calculating the covariance matrix of the polynomial terms, the Generalized Total Least Squares method is used to find the model parameters, and thus the non-linear components. Finally, a bootstrap technique is used to determine confidence intervals of the estimated values. Results for synthetic data are shown.

MOPF32	Development of Gated Turn-by-Turn Position Monitor System for the Optics Measurement During Collision of SuperKEKB	BPM, betatron, controls, coupling	295
	M. Tobiyama, H. Fukuma, H. Ishii, K. Mori KEK, Ibaraki, Japan
	Gated turn-by-turn monitor system to measure optics functions using non-colliding bunch has been developed for SuperKEKB accelerators. With the fast, glitch cancelling beam switch, beam position of the target bunch will be measured without affecting the fine COD measurement using narrow-band detectors. The gate timing and the bunch position detection are controlled by the Spartan-6 FPGA. The performance of the system, such as the gate timing jitter, data transfer speed from the system to EPICS IOC and the noise effect to the downstream narrow-band detector are reported.
	Poster MOPF32 [1.531 MB]

TUCL1	Overview of Imaging Sensors and Systems Used in Beam Instrumentation	radiation, electron, controls, instrumentation	331
	E. Bravin CERN, Geneva, Switzerland
	The presentation will give an overview of applicable image sensors and sensor systems for an application in the beam instrumentation. The overview will cover fast imaging cameras as well as sensors and cameras to be used in radiation fields. The critical parameters will be discussed and measurements presented if available. Frame grabbers and digital cameras will also be included in the presentation.
	Slides TUCL1 [8.924 MB]

TUPF09	Commissioning Experience and First Results From the New SLS Beam Size Monitor	SLS, polarization, emittance, alignment	519
	V. Schlott, M. Rohrer, A. Saá Hernández, A. Streun PSI, Villigen PSI, Switzerland Å. Andersson, J. Breunlin MAX-lab, Lund, Sweden N. Milas LNLS, Campinas, Brazil
	Funding: The presented work has received funding from the European Commission under FP-7-INFRASTRUCTURES-2010-1/INFRA-2010- 2.2.11 project TIARA (CNI-PP). Grant agreement no. 261905. In the context of the TIARA work package “SLS vertical emittance tuning” (SVET), an extremely small vertical beam size of 3.6 μm, corresponding to a vertical emittance of 0.9 pm, was verified using an optical monitor based on imaging of pi-polarized light. Since the existing beam size monitor reached its limit of resolution, a new monitor beam line was designed and installed at the 08BD bending magnet of the storage ring of the Swiss Light Source SLS. Larger magnification and operation at shorter wavelength provide improved spatial resolution. Reflective optics enables convenient switching between different wavelengths. An optical table is located in a hutch outside the storage ring tunnel to provide access during operation. Movable obstacles in the beam path create interference patterns and thus provide redundancy of model based analysis of the images. In this paper we report on our commissioning experience and provide a comparison of the different measurement methods at different wavelengths.
	Poster TUPF09 [0.292 MB]

WEAL1	Large Aperture X-ray Monitors for Beam Profile Diagnostics	photon, emittance, undulator, diagnostics	608
	C.A. Thomas, G. Rehm Diamond, Oxfordshire, United Kingdom F. Ewald ESRF, Grenoble, France J.W. Flanagan KEK, Ibaraki, Japan
	Emittance is one of the main characteristic properties of a beam of particles in an accelerator, and it is measured generally by means of the particle beam profile. In particular, when the beam of particles is emitting an X-ray photon beam, a non perturbative way of measuring the particle beam profile is to image it using the emitted X-ray photon beam. Over the years, numerous X-ray imaging methods have been developed, fulfilling the requirements imposed by a particle beam becoming smaller, and approaching micron size for electron beam machine with vertical emittance of the order of 1pm-rad. In this paper, we will first recall the properties of the X-ray photon as function of source and its properties. From this we will derive some natural definition of a large aperture X-ray imaging system. We will then use this selection criterion to select a number of X-ray imaging devices used as a beam profile diagnostics in an attempt to give an overview of what has been achieved and what is possible to achieve with the selected devices.
	Slides WEAL1 [7.499 MB]

WEPF15	High-Power Tests at CesrTA of X-ray Optics Elements for SuperKEKB	DIAMOND, simulation, factory, LEFT	844
	J.W. Flanagan, A. Arinaga, H. Fukuma, H. Ikeda KEK, Ibaraki, Japan A. Lyndaker, D.P. Peterson, N.T. Rider Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	X-ray beam size monitors at SuperKEKB must withstand high, sustained incident power loads. Two prototype optics elements were fabricated and tested at CesrTA, using incident X-ray power densities comparable to those expected at the SuperKEKB LER. One element was based on a silicon substrate, the other a CVD diamond substrate, with each substrate supporting a coded aperture mask pattern in gold on its surface. The diamond substrate mask showed superior performance to the silicon substrate mask, with the the mask pattern on the silicon substrate melting at the highest incident power level tested, where the diamond-substrate mask survived. We will present here the high-power test results, along with analysis of X-ray power absorption and heat transfer in the two prototype elements, and the resulting implications for the design of the optics, beam line and heat sink for SuperKEKB.

Paper

Title

Other Keywords

Page

MOPC34

Longitudinal Beam Profile Monitor for Investigating the Microbunching Instability at Diamond Light Source

DIAMOND, radiation, longitudinal, storage-ring

143

W. Shields, R. Bartolini, A.F.D. Morgan, G. Rehm
Diamond, Oxfordshire, United Kingdom
R. Bartolini, P. Karataev
JAI, Oxford, United Kingdom
P. Karataev
Royal Holloway, University of London, Surrey, United Kingdom

An investigation into the microbunching instability at Diamond Light Source has recently been conducted. Beyond the instability threshold, the bunch emits bursts of coherent synchrotron radiation with wavelengths comparable to the bunch length or shorter. The operating conditions for producing the instability include both normal optics, and low-alpha optics, where the bunch length can be shortened to a few picoseconds. A Michelson interferometer has been designed and installed utilising a silicon crystal wafer beamsplitter. Large bandwidth, room temperature pyroelectric detectors and low-noise, fast-response Schottky Barrier diode detectors have been employed to generate interferograms. In this paper, we describe the observed spectral content and the resulting calculated bunch length.

MOPF05

Operating Semiconductor Timepix Detector with Optical Readout in an Extremely Hostile Environment of Laser Plasma Acceleration Experiment

laser, vacuum, target, shielding

208

L. Pribyl
Czech Republic Academy of Sciences, Institute of Physics, Prague, Czech Republic

The laser plasma acceleration (LPA) experiments produce very intensive electromagnetic pulses (EMP) complicating operation of sensitive electronic detectors. We present our experience with new optical readout and EMP shielding for hybrid silicon pixel detector Timepix*, which enabled its operation in an extremely hostile electromagnetic LPA environment. The Timepix detector provides a matrix of 256x256 spectroscopic channels with 55 μm pitch. An optical readout, battery powering and shielding against electromagnetic pulses (EMP) have been developed as part of the ELI Beamlines/IEAP project for the detector Timepix and it significantly improved its resistance to EMP with respect to previous setup using metallic cables for both data acquisition and powering. The new optical setup was successfully tested under vacuum at Prague Asterix Laser System (PALS) during experiments with laser pulses of energies up to 700 J and duration of 350 ps bombarding thin foil solid target. Electromagnetic field was measured both outside the vacuum chamber and inside. The recorded spectrometric data were analyzed and interpreted in a context of an independent experimental campaign run in parallel.
* X. Llopart et al.: Timepix, a 65k Programmable Pixel Readout Chip for Arrival Time, Energy and/or Photon Counting Measurements, Nucl. Instr. and Meth. in Phys. Res. A. Vol. 581 (2007), p485

MOPF06

Beam Profile Monitors at REGAE

electron, diagnostics, photon, SNR

212

H. Delsim-Hashemi, K. Flöttmann
DESY, Hamburg, Germany
S. Bayesteh
Uni HH, Hamburg, Germany

A new linac is commissioned at DESY mainly as the electron source for femtosecond electron diffraction facility REGAE (Relativistic Electron Gun for Atomic Exploration). REGAE enables studies on structural dynamics of atomic transition states occurring in the sub-hundred femtosecond time-scale. REGAE comprises a photo-cathode gun followed by normal conducting 1.5 cell rf-cavity to provide sub pC electron-bunches of 2-5 MeV with a coherence length of 30nm. In order to produce and maintain such electron bunches, sophisticated single-shot diagnostics are desired e.g. emittance, energy, energy-spread and bunch-length measurement. REGAE rep-rate can be up to 50 Hz. This relatively high rep-rate makes it more challenging to deal with low intensity detection especially in single-shot mode. In this contribution the conceptual ideas, realization and results of transversal diagnostics will be presented.

MOPF07

Turn by Turn Profile Monitors for the CERN SPS and LHC

LHC, OTR, SPS, proton

216

S. Burger, A. Boccardi, E. Bravin, A. Goldblatt, A. Ravni, F. Roncarolo, R.S. Sautier
CERN, Geneva, Switzerland

In order to preserve the transverse beam emittance along the acceleration chain it is important that the optics of the transfer lines is perfectly matched to the optics of the rings. Special monitors capable of measuring the beam profiles with a turn by turn resolution are very helpful in this respect. A new type of matching monitor has been developed at CERN for the SPS and LHC machines. This monitor relies on imaging OTR light by mean of a fast line scan CMOS and an asymmetric optical system based on cylindrical lenses. This contribution describes the design of this monitor, presents the results obtained during the 2012-13 run and outlines the plans for further improving the design.

MOPF08

Design and Performance of the Upgraded LHC Synchrotron Light Monitor

LHC, focusing, undulator, dipole

220

A. Goldblatt, E. Bravin, F. Roncarolo, G. Trad
CERN, Geneva, Switzerland

The LHC is equipped with two synchrotron radiation systems, one per beam, used to measure the transverse bunch distributions. The light emitted by a superconducting undulator and/or by a dipole magnet (depending on beam energy) is intercepted by an extraction mirror in vacuum and sent through a viewport to the imaging Beam Synchrotron Radiation Telescope (BSRT). The first version of the telescope, used from 2009 to mid 2012, was based on spherical focusing mirrors in order to minimize chromatic aberrations. However, this required a very complicated delay line in order to switch the focus between the two different light sources as a function of beam energy. A new system based on optical lenses was designed and installed in mid 2012 in order to simplify the optical line and thus reduce misalignment and focusing errors. The first results with LHC beam using this new system showed a significant reduction in the correction factor required to match the emittance as measured by wire scanners. This contribution discusses the performance of the new optical system, presenting the LHC results and comparing simulations with measurement performed in the laboratory using a BSRT replica.

MOPF28

Optics Non-Linear Components Measurement Using BPM Signals

focusing, BPM, beam-losses, synchrotron

279

M. Alhumaidi, A.M. Zoubir
TU Darmstadt, Darmstadt, Germany

The knowledge of linear and non-linear errors in circular accelerator optics is very crucial for controlling and compensating resonances and their consequent beam losses. This is indispensable, especially for high intensity machines. Fortunately, the relationship between the recorded beam offset signals at the BPMs is a manifestation of the accelerator optics, and can therefore be exploited in the determination of the optics linear and non-linear components. We propose a novel method for estimating lattice non-linear components located in-between the positions of two BPMs by analyzing the beam offset signals of a BPMs triple containing these two BPMs. Depending on the non-linear components in-between the locations of the BPMs triple, the relationship between the beam offsets follows a multivariate polynomial. After calculating the covariance matrix of the polynomial terms, the Generalized Total Least Squares method is used to find the model parameters, and thus the non-linear components. Finally, a bootstrap technique is used to determine confidence intervals of the estimated values. Results for synthetic data are shown.

MOPF32

Development of Gated Turn-by-Turn Position Monitor System for the Optics Measurement During Collision of SuperKEKB

BPM, betatron, controls, coupling

295

M. Tobiyama, H. Fukuma, H. Ishii, K. Mori
KEK, Ibaraki, Japan

Gated turn-by-turn monitor system to measure optics functions using non-colliding bunch has been developed for SuperKEKB accelerators. With the fast, glitch cancelling beam switch, beam position of the target bunch will be measured without affecting the fine COD measurement using narrow-band detectors. The gate timing and the bunch position detection are controlled by the Spartan-6 FPGA. The performance of the system, such as the gate timing jitter, data transfer speed from the system to EPICS IOC and the noise effect to the downstream narrow-band detector are reported.

Poster MOPF32 [1.531 MB]

TUCL1

Overview of Imaging Sensors and Systems Used in Beam Instrumentation

radiation, electron, controls, instrumentation

331

E. Bravin
CERN, Geneva, Switzerland

The presentation will give an overview of applicable image sensors and sensor systems for an application in the beam instrumentation. The overview will cover fast imaging cameras as well as sensors and cameras to be used in radiation fields. The critical parameters will be discussed and measurements presented if available. Frame grabbers and digital cameras will also be included in the presentation.

Slides TUCL1 [8.924 MB]

TUPF09

Commissioning Experience and First Results From the New SLS Beam Size Monitor

SLS, polarization, emittance, alignment

519

V. Schlott, M. Rohrer, A. Saá Hernández, A. Streun
PSI, Villigen PSI, Switzerland
Å. Andersson, J. Breunlin
MAX-lab, Lund, Sweden
N. Milas
LNLS, Campinas, Brazil

Funding: The presented work has received funding from the European Commission under FP-7-INFRASTRUCTURES-2010-1/INFRA-2010- 2.2.11 project TIARA (CNI-PP). Grant agreement no. 261905.
In the context of the TIARA work package “SLS vertical emittance tuning” (SVET), an extremely small vertical beam size of 3.6 μm, corresponding to a vertical emittance of 0.9 pm, was verified using an optical monitor based on imaging of pi-polarized light. Since the existing beam size monitor reached its limit of resolution, a new monitor beam line was designed and installed at the 08BD bending magnet of the storage ring of the Swiss Light Source SLS. Larger magnification and operation at shorter wavelength provide improved spatial resolution. Reflective optics enables convenient switching between different wavelengths. An optical table is located in a hutch outside the storage ring tunnel to provide access during operation. Movable obstacles in the beam path create interference patterns and thus provide redundancy of model based analysis of the images. In this paper we report on our commissioning experience and provide a comparison of the different measurement methods at different wavelengths.

Poster TUPF09 [0.292 MB]

WEAL1

Large Aperture X-ray Monitors for Beam Profile Diagnostics

photon, emittance, undulator, diagnostics

608

C.A. Thomas, G. Rehm
Diamond, Oxfordshire, United Kingdom
F. Ewald
ESRF, Grenoble, France
J.W. Flanagan
KEK, Ibaraki, Japan

Emittance is one of the main characteristic properties of a beam of particles in an accelerator, and it is measured generally by means of the particle beam profile. In particular, when the beam of particles is emitting an X-ray photon beam, a non perturbative way of measuring the particle beam profile is to image it using the emitted X-ray photon beam. Over the years, numerous X-ray imaging methods have been developed, fulfilling the requirements imposed by a particle beam becoming smaller, and approaching micron size for electron beam machine with vertical emittance of the order of 1pm-rad. In this paper, we will first recall the properties of the X-ray photon as function of source and its properties. From this we will derive some natural definition of a large aperture X-ray imaging system. We will then use this selection criterion to select a number of X-ray imaging devices used as a beam profile diagnostics in an attempt to give an overview of what has been achieved and what is possible to achieve with the selected devices.

Slides WEAL1 [7.499 MB]

WEPF15

High-Power Tests at CesrTA of X-ray Optics Elements for SuperKEKB

DIAMOND, simulation, factory, LEFT

844

J.W. Flanagan, A. Arinaga, H. Fukuma, H. Ikeda
KEK, Ibaraki, Japan
A. Lyndaker, D.P. Peterson, N.T. Rider
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

X-ray beam size monitors at SuperKEKB must withstand high, sustained incident power loads. Two prototype optics elements were fabricated and tested at CesrTA, using incident X-ray power densities comparable to those expected at the SuperKEKB LER. One element was based on a silicon substrate, the other a CVD diamond substrate, with each substrate supporting a coded aperture mask pattern in gold on its surface. The diamond substrate mask showed superior performance to the silicon substrate mask, with the the mask pattern on the silicon substrate melting at the highest incident power level tested, where the diamond-substrate mask survived. We will present here the high-power test results, along with analysis of X-ray power absorption and heat transfer in the two prototype elements, and the resulting implications for the design of the optics, beam line and heat sink for SuperKEKB.