IBIC2014 - List of Authors (Lefevre, T.)

Paper	Title	Page
MOPF14	Vertical Beam Size Measurement at CesrTA Using Diffraction Radiation	77
	L.M. Bobb, T. Aumeyr, P. Karataev JAI, Egham, Surrey, United Kingdom T. Aumeyr, P. Karataev Royal Holloway, University of London, Surrey, United Kingdom M.G. Billing, J.V. Conway Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA L.M. Bobb DLS, Oxfordshire, United Kingdom E. Bravin, T. Lefèvre, S. Mazzoni, H. Schmickler CERN, Geneva, Switzerland
	Over recent years the first Diffraction Radiation (DR) beam size monitor has been tested on a circular machine. At CesrTA, Cornell University, USA, the sensitivity and limitations of the DR monitor for vertical beam size measurement has been investigated. DR emitted from 1 and 0.5 mm target apertures was observed at 400 and 600 nm wavelengths. In addition, interference between the DR signals emitted by the target and mask has been observed. In this report, we present the recent observations and discuss areas for improvement.
	Poster MOPF14 [3.379 MB]
Export •	reference for this paper to ※ LaTeX, ※ Text, ※ IS/RefMan, ※ EndNote (xml)

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

WEPF05	Simulation of the Beam Dump for a High Intensity Electron Gun	536
	A. Jeff, S. Döbert, T. Lefèvre CERN, Geneva, Switzerland A. Jeff The University of Liverpool, Liverpool, United Kingdom K. Pepitone CEA, LE BARP cedex, France
	The CLIC Drive Beam is a high-intensity pulsed electron beam. A test facility for the Drive Beam electron gun will soon be commissioned at CERN. In this contribution we outline the design of a beam dump / Faraday cup capable of resisting the beam’s thermal load. The test facility will operate initially up to 140 keV. At such low energies, the electrons are absorbed very close to the surface of the dump, leading to a large energy deposition density in this thin layer. In order not to damage the dump, the beam must be spread over a large surface. For this reason, a small-angled cone has been chosen. Simulations using geant4 have been performed to estimate the distribution of energy deposition in the dump. The heat transport both within the electron pulse and between pulses has been modelled using finite element methods to check the resistance of the dump at high repetition rates. In addition, the possibility of using a moveable dump to measure the beam profile and emittance is discussed.
	Poster WEPF05 [0.224 MB]
Export •	reference for this paper to ※ LaTeX, ※ Text, ※ IS/RefMan, ※ EndNote (xml)

Paper

Title

Page

Vertical Beam Size Measurement at CesrTA Using Diffraction Radiation

77

L.M. Bobb, T. Aumeyr, P. Karataev
JAI, Egham, Surrey, United Kingdom
T. Aumeyr, P. Karataev
Royal Holloway, University of London, Surrey, United Kingdom
M.G. Billing, J.V. Conway
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
L.M. Bobb
DLS, Oxfordshire, United Kingdom
E. Bravin, T. Lefèvre, S. Mazzoni, H. Schmickler
CERN, Geneva, Switzerland

Over recent years the first Diffraction Radiation (DR) beam size monitor has been tested on a circular machine. At CesrTA, Cornell University, USA, the sensitivity and limitations of the DR monitor for vertical beam size measurement has been investigated. DR emitted from 1 and 0.5 mm target apertures was observed at 400 and 600 nm wavelengths. In addition, interference between the DR signals emitted by the target and mask has been observed. In this report, we present the recent observations and discuss areas for improvement.

Poster MOPF14 [3.379 MB]

Export •

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

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]

Export •

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

WEPF05

Simulation of the Beam Dump for a High Intensity Electron Gun

536

A. Jeff, S. Döbert, T. Lefèvre
CERN, Geneva, Switzerland
A. Jeff
The University of Liverpool, Liverpool, United Kingdom
K. Pepitone
CEA, LE BARP cedex, France

The CLIC Drive Beam is a high-intensity pulsed electron beam. A test facility for the Drive Beam electron gun will soon be commissioned at CERN. In this contribution we outline the design of a beam dump / Faraday cup capable of resisting the beam’s thermal load. The test facility will operate initially up to 140 keV. At such low energies, the electrons are absorbed very close to the surface of the dump, leading to a large energy deposition density in this thin layer. In order not to damage the dump, the beam must be spread over a large surface. For this reason, a small-angled cone has been chosen. Simulations using geant4 have been performed to estimate the distribution of energy deposition in the dump. The heat transport both within the electron pulse and between pulses has been modelled using finite element methods to check the resistance of the dump at high repetition rates. In addition, the possibility of using a moveable dump to measure the beam profile and emittance is discussed.

Poster WEPF05 [0.224 MB]

Export •

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