IBIC2014 - Classification: Beam Profile Monitors

Paper	Title	Page
MOCYB3	Longitudinal Laser Wire at SNS	12
	A.P. Zhukov, A.V. Aleksandrov, Y. Liu ORNL, Oak Ridge, Tennessee, USA
	Funding: ORNL/SNS is managed by UT-Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725. This paper describes a longitudinal H⁻ beam profile scanner that utilizes laser light to detach convoy electrons and an MCP to collect and measure these electrons. The scanner is located in MEBT with H⁻ energy of 2.5MeV and an RF frequency 402.5MHz. The picosecond pulsed laser runs at 80.5MHz in sync with the accelerator RF. The laser beam is delivered to the beam line through a 30m optical fiber. The pulse width after the fiber transmission measures about 10ps. Scanning the laser phase effectively allows measurements to move along ion bunch longitudinal position. We are able to reliably measure production beam bunch length with this method. The biggest problem we have encountered is background signal from electrons being stripped by vacuum. Several techniques of signal detection are discussed.
	Slides MOCYB3 [4.519 MB]
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MOPD26	A Bunch Extension Monitor for the Spiral2 LINAC	212
	J.L. Vignet, R.V. Revenko GANIL, Caen, France
	Measurements of the longitudinal shape of bunched beam particles are crucial for optimization and control of LINAC beam parameters and maximization of its integrated luminosity. The non-interceptive bunch extension monitor for the LINAC at the SPIRAL2 facility is being developed at GANIL. Five bunch extension monitors will be installed at the beginning of the LINAC between superconducting cavities. The principle of operation is based on the registration of x-rays induced by ions of accelerator beam interacting with a thin tungsten wire positioned on the beam path. The monitor consists of two parts: a system for wire insertion and positioning, and an x-ray detector based on microchannel plates (MCPs). A detector prototype has been developed over the past three years and was tested using both protons and heavy ions beams.
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TUCYB3	SwissFEL Beam Profile Monitor	259
	R. Ischebeck, E. Prat, V. Schlott, V.G. Thominet PSI, Villigen PSI, Switzerland P. Krejcik, H. Loos SLAC, Menlo Park, California, USA M. Yan DESY, Hamburg, Germany
	We have developed a beam profile monitor that allows us to measure two-dimensional electron beam profiles for highly compressed electron bunches. Such bunches have plagued profile measurements in optical transition radiation monitors in the past, because coherent radiation entering the optical system has invalidated the images and even destroyed cameras. The present design makes use of a scintillating crystal, and directs coherent transition radiation away from the optical axis by careful choice of the angle. When observing Snell's law of refraction as well as the Scheimpflug imaging condition, a resolution better than the thickness of the scintillator can be achieved. We will present measurements performed at the SwissFEL Injector Test Facility and at the Linac Coherent Light Source. The high resolution and excellent sensitivity of this monitor make it ideal for installation in SwissFEL.
	Slides TUCYB3 [42.624 MB]
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TUIZB1	Radiation Sources and Their Application for Beam Profile Diagnostics	263
	G. Kube DESY, Hamburg, Germany
	Radiation generated by high-energy particle beams is widely used for beam diagnostic purposes. Depending on the mechanism of radiation generation, the emitted wavelength range extends from the THz up to the X-ray region, thus allowing the measurement of beam profiles in the longitudinal and the transverse plane over a wide range. In this talk, basic considerations for radiation based profile measurements will be discussed with special emphasis on the mechanism of radiation generation and the impact on beam diagnostic measurements.
	Slides TUIZB1 [4.803 MB]
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TUCZB1	Novel Emittance Diagnostics for Diffraction Limited Light Sources Based on X-ray Fresnel Diffractometry	274
	M. Masaki, Y. Shimosaki, S. Takano, M. Takao JASRI/SPring-8, Hyogo-ken, Japan
	A novel emittance diagnostics technique with high sensitivity using X-ray Fresnel diffraction by a single slit has been developed to measure micron-order electron beam sizes at insertion devices (IDs) of photon beamlines. The X-ray Fresnel diffractometry (XFD)* is promising for diagnostics especially of a so-called diffraction limited storage ring (DLSR) with ultra-low emittance. In the DLSR, due to inevitable field errors of strong quadrupole and sextupole magnets, unwanted distortion of lattice functions and local betatron coupling will result in a different light source size at each beamline. Therefore, measurements of electron beam sizes at the ID source points will be essential to ensure the absence of degradation of brilliance and transverse coherence of radiation at the beamlines. The XFD observes a double-lobed diffraction pattern that emerges by optimizing the single slit width. The principle is based on a correlation between the depth of a median dip in the double-lobed pattern and the light source size at the ID. The validity of the new technique was theoretically and experimentally studied. The achievable resolution of the XFD will be also discussed. * M. Masaki, et al.,"X-ray Fresnel Diffractometry for Ultra-Low Emittance Diagnostics of Next Generation Synchrotron Light Sources", submitted to Phys. Rev.ST-AB.
	Slides TUCZB1 [5.456 MB]
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TUCZB3	A Quantum Gas Jet for Non-Invasive Beam Profile Measurement	284
	A. Jeff, E.B. Holzer, T. Lefèvre CERN, Geneva, Switzerland A. Jeff, V. Tzoganis, C.P. Welsch, H.D. Zhang The University of Liverpool, Liverpool, United Kingdom V. Tzoganis, C.P. Welsch, H.D. Zhang Cockcroft Institute, Warrington, Cheshire, United Kingdom
	A novel instrument for accelerator beam diagnostics is being developed by using De Broglie-wave focusing to create an ultra-thin neutral gas jet. Scanning the gas jet across a particle beam while measuring the interaction products, the beam profile can be measured. Such a jet scanner will provide an invaluable diagnostic tool in beams which are too intense for the use of wire scanners, such as the proposed CLIC Drive Beam. In order to create a sufficiently thin jet, a focusing element working on the DeBroglie wavelength of the Helium atom has been designed. Following the principles of the Photon Sieve, we have constructed an Atomic Sieve consisting of 5230 nano-holes etched into a thin film of silicon nitride. When a quasi-monochromatic Helium jet is incident on the sieve, an interference pattern with a single central maximum is created. The stream of Helium atoms passing through this central maximum is much narrower than a conventional gas jet. The first experiences with this device are presented here, along with plans for further tests.
	Slides TUCZB3 [13.880 MB]
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Paper

Title

Page

Longitudinal Laser Wire at SNS

12

A.P. Zhukov, A.V. Aleksandrov, Y. Liu
ORNL, Oak Ridge, Tennessee, USA

Funding: ORNL/SNS is managed by UT-Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725.
This paper describes a longitudinal H⁻ beam profile scanner that utilizes laser light to detach convoy electrons and an MCP to collect and measure these electrons. The scanner is located in MEBT with H⁻ energy of 2.5MeV and an RF frequency 402.5MHz. The picosecond pulsed laser runs at 80.5MHz in sync with the accelerator RF. The laser beam is delivered to the beam line through a 30m optical fiber. The pulse width after the fiber transmission measures about 10ps. Scanning the laser phase effectively allows measurements to move along ion bunch longitudinal position. We are able to reliably measure production beam bunch length with this method. The biggest problem we have encountered is background signal from electrons being stripped by vacuum. Several techniques of signal detection are discussed.

Slides MOCYB3 [4.519 MB]

Export •

reference for this paper to ※ LaTeX, ※ Text, ※ IS/RefMan, ※ EndNote (xml)

MOPD26

A Bunch Extension Monitor for the Spiral2 LINAC

212

J.L. Vignet, R.V. Revenko
GANIL, Caen, France

Measurements of the longitudinal shape of bunched beam particles are crucial for optimization and control of LINAC beam parameters and maximization of its integrated luminosity. The non-interceptive bunch extension monitor for the LINAC at the SPIRAL2 facility is being developed at GANIL. Five bunch extension monitors will be installed at the beginning of the LINAC between superconducting cavities. The principle of operation is based on the registration of x-rays induced by ions of accelerator beam interacting with a thin tungsten wire positioned on the beam path. The monitor consists of two parts: a system for wire insertion and positioning, and an x-ray detector based on microchannel plates (MCPs). A detector prototype has been developed over the past three years and was tested using both protons and heavy ions beams.

Export •

reference for this paper to ※ LaTeX, ※ Text, ※ IS/RefMan, ※ EndNote (xml)

TUCYB3

SwissFEL Beam Profile Monitor

259

R. Ischebeck, E. Prat, V. Schlott, V.G. Thominet
PSI, Villigen PSI, Switzerland
P. Krejcik, H. Loos
SLAC, Menlo Park, California, USA
M. Yan
DESY, Hamburg, Germany

We have developed a beam profile monitor that allows us to measure two-dimensional electron beam profiles for highly compressed electron bunches. Such bunches have plagued profile measurements in optical transition radiation monitors in the past, because coherent radiation entering the optical system has invalidated the images and even destroyed cameras. The present design makes use of a scintillating crystal, and directs coherent transition radiation away from the optical axis by careful choice of the angle. When observing Snell's law of refraction as well as the Scheimpflug imaging condition, a resolution better than the thickness of the scintillator can be achieved. We will present measurements performed at the SwissFEL Injector Test Facility and at the Linac Coherent Light Source. The high resolution and excellent sensitivity of this monitor make it ideal for installation in SwissFEL.

Slides TUCYB3 [42.624 MB]

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reference for this paper to ※ LaTeX, ※ Text, ※ IS/RefMan, ※ EndNote (xml)

TUIZB1

Radiation Sources and Their Application for Beam Profile Diagnostics

263

G. Kube
DESY, Hamburg, Germany

Radiation generated by high-energy particle beams is widely used for beam diagnostic purposes. Depending on the mechanism of radiation generation, the emitted wavelength range extends from the THz up to the X-ray region, thus allowing the measurement of beam profiles in the longitudinal and the transverse plane over a wide range. In this talk, basic considerations for radiation based profile measurements will be discussed with special emphasis on the mechanism of radiation generation and the impact on beam diagnostic measurements.

Slides TUIZB1 [4.803 MB]

Export •

reference for this paper to ※ LaTeX, ※ Text, ※ IS/RefMan, ※ EndNote (xml)

TUCZB1

Novel Emittance Diagnostics for Diffraction Limited Light Sources Based on X-ray Fresnel Diffractometry

274

M. Masaki, Y. Shimosaki, S. Takano, M. Takao
JASRI/SPring-8, Hyogo-ken, Japan

A novel emittance diagnostics technique with high sensitivity using X-ray Fresnel diffraction by a single slit has been developed to measure micron-order electron beam sizes at insertion devices (IDs) of photon beamlines. The X-ray Fresnel diffractometry (XFD)* is promising for diagnostics especially of a so-called diffraction limited storage ring (DLSR) with ultra-low emittance. In the DLSR, due to inevitable field errors of strong quadrupole and sextupole magnets, unwanted distortion of lattice functions and local betatron coupling will result in a different light source size at each beamline. Therefore, measurements of electron beam sizes at the ID source points will be essential to ensure the absence of degradation of brilliance and transverse coherence of radiation at the beamlines. The XFD observes a double-lobed diffraction pattern that emerges by optimizing the single slit width. The principle is based on a correlation between the depth of a median dip in the double-lobed pattern and the light source size at the ID. The validity of the new technique was theoretically and experimentally studied. The achievable resolution of the XFD will be also discussed.
* M. Masaki, et al.,"X-ray Fresnel Diffractometry for Ultra-Low Emittance Diagnostics of Next Generation Synchrotron Light Sources", submitted to Phys. Rev.ST-AB.

Slides TUCZB1 [5.456 MB]

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TUCZB3

A Quantum Gas Jet for Non-Invasive Beam Profile Measurement

284

A. Jeff, E.B. Holzer, T. Lefèvre
CERN, Geneva, Switzerland
A. Jeff, V. Tzoganis, C.P. Welsch, H.D. Zhang
The University of Liverpool, Liverpool, United Kingdom
V. Tzoganis, C.P. Welsch, H.D. Zhang
Cockcroft Institute, Warrington, Cheshire, United Kingdom

A novel instrument for accelerator beam diagnostics is being developed by using De Broglie-wave focusing to create an ultra-thin neutral gas jet. Scanning the gas jet across a particle beam while measuring the interaction products, the beam profile can be measured. Such a jet scanner will provide an invaluable diagnostic tool in beams which are too intense for the use of wire scanners, such as the proposed CLIC Drive Beam. In order to create a sufficiently thin jet, a focusing element working on the DeBroglie wavelength of the Helium atom has been designed. Following the principles of the Photon Sieve, we have constructed an Atomic Sieve consisting of 5230 nano-holes etched into a thin film of silicon nitride. When a quasi-monochromatic Helium jet is incident on the sieve, an interference pattern with a single central maximum is created. The stream of Helium atoms passing through this central maximum is much narrower than a conventional gas jet. The first experiences with this device are presented here, along with plans for further tests.

Slides TUCZB3 [13.880 MB]

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