DIPAC2011 - List of Authors (Adroit, G.)

Paper	Title	Page
TUPD46	Beam Species Fraction Measurement using Doppler Shift Method with FUJIKURA Fiberscope for IFMIF-EVEDA Injector	407
	F. Senée, B. Pottin CEA/DSM/IRFU, France G. Adroit, R. Gobin, O. Tuske CEA/IRFU, Gif-sur-Yvette, France A. Olivier IPN, Orsay, France
	To characterize high intensity ion beam in low energy beam transport line, diagnostics based on residual gas molecule excitation are commonly used. An example is CCD sensors for beam intensity, beam position and beam profile measurements. At CEA/Saclay with the SILHI injector, beam images transports from viewport to sensor have been performed with a fiberscope. Such technique will be used to transport the beam images away from the irradiated zone of the IFMIF-EVEDA tunnel which requires using hardened radiation devices. Indeed, the (D,d) reaction, due to interaction of 140 mA-100 keV deuteron beam with vacuum pipes or scrapers, leads to high neutron and gamma ray flux. As a consequence, in addition to CID cameras for online beam positioning and shape measurements, a 20 m long Fujikura fiberscope has been selected to analyze species fraction using the Doppler shift method. Preliminary measurements have been performed with the SILHI beam to characterize the fiberscope. Its spatial resolution and transmission as well as a CCD sensor and fiberscope comparison are presented. Beam species fractions with and without the use of fiberscope will be also reported.

TUPD58	Non-interceptive Profile Measurements using an Optical-based Tomography Technique	437
	C.M. Mateo, G. Adroit, G. Ferrand, A. France, R. Gobin, S. Nyckees, Y. Sauce, F. Senée, O. Tuske CEA/IRFU, Gif-sur-Yvette, France
	Funding: This work is supported by the DITANET Marie Curie European network Most of the charged particle beam shapes do not possess symmetry. In such cases, diagnostic measurement obtained in one direction is not enough to reconstruct the spatial distribution of the beam. The use of intense beams which demands for non-interceptive diagnostic devices posed another challenge in measuring the beam’s spatial distribution. At CEA Saclay and within the DITANET framework, the use of tomography combined with optical diagnostics to develop a non-interceptive transverse profile monitor is under development. This profile monitor is presently tested on the BETSI test bench. In this contribution, a tomography algorithm suited for beam profile measurements is presented. This algorithm is based on the formulation of iterative Algebraic Reconstruction Technique (ART) problem and the Maximum-Likelihood Expectation Maximization (MLEM) for the iteration step. The algorithm is optimized within the limit of using 6 projections only. Several beam shapes are generated and then reconstructed computationally. Actual measurements in the BETSI test bench are also done to verify the tomographic reconstruction process.

Paper

Title

Page

Beam Species Fraction Measurement using Doppler Shift Method with FUJIKURA Fiberscope for IFMIF-EVEDA Injector

407

F. Senée, B. Pottin
CEA/DSM/IRFU, France
G. Adroit, R. Gobin, O. Tuske
CEA/IRFU, Gif-sur-Yvette, France
A. Olivier
IPN, Orsay, France

To characterize high intensity ion beam in low energy beam transport line, diagnostics based on residual gas molecule excitation are commonly used. An example is CCD sensors for beam intensity, beam position and beam profile measurements. At CEA/Saclay with the SILHI injector, beam images transports from viewport to sensor have been performed with a fiberscope. Such technique will be used to transport the beam images away from the irradiated zone of the IFMIF-EVEDA tunnel which requires using hardened radiation devices. Indeed, the (D,d) reaction, due to interaction of 140 mA-100 keV deuteron beam with vacuum pipes or scrapers, leads to high neutron and gamma ray flux. As a consequence, in addition to CID cameras for online beam positioning and shape measurements, a 20 m long Fujikura fiberscope has been selected to analyze species fraction using the Doppler shift method. Preliminary measurements have been performed with the SILHI beam to characterize the fiberscope. Its spatial resolution and transmission as well as a CCD sensor and fiberscope comparison are presented. Beam species fractions with and without the use of fiberscope will be also reported.

TUPD58

Non-interceptive Profile Measurements using an Optical-based Tomography Technique

437

C.M. Mateo, G. Adroit, G. Ferrand, A. France, R. Gobin, S. Nyckees, Y. Sauce, F. Senée, O. Tuske
CEA/IRFU, Gif-sur-Yvette, France

Funding: This work is supported by the DITANET Marie Curie European network
Most of the charged particle beam shapes do not possess symmetry. In such cases, diagnostic measurement obtained in one direction is not enough to reconstruct the spatial distribution of the beam. The use of intense beams which demands for non-interceptive diagnostic devices posed another challenge in measuring the beam’s spatial distribution. At CEA Saclay and within the DITANET framework, the use of tomography combined with optical diagnostics to develop a non-interceptive transverse profile monitor is under development. This profile monitor is presently tested on the BETSI test bench. In this contribution, a tomography algorithm suited for beam profile measurements is presented. This algorithm is based on the formulation of iterative Algebraic Reconstruction Technique (ART) problem and the Maximum-Likelihood Expectation Maximization (MLEM) for the iteration step. The algorithm is optimized within the limit of using 6 projections only. Several beam shapes are generated and then reconstructed computationally. Actual measurements in the BETSI test bench are also done to verify the tomographic reconstruction process.