DIPAC2011 - List of Keywords (beam-transport)

Paper	Title	Other Keywords	Page
MOPD12	Expressing Properties of BPM Measurement System in Terms of Error Emittance and Error Twiss Parameters	emittance, betatron, FEL, focusing	62
	V. Balandin, W. Decking, N. Golubeva DESY, Hamburg, Germany
	The determination of variations in the beam position and in the beam energy using BPM readings is one of the standard problems of accelerator physics. If the optical model of the beam line and BPM resolutions are known, the typical choice is to let jitter parameters be a solution of the weighted linear least squares problem. For transversely uncoupled motion this least squares problem can be solved analytically, but the direct usage of the obtained solution as a tool for designing a BPM measurement system is not straightforward. A better understanding of the nature of the problem is needed. In this paper we show that properties of the BPM measurement system can be described in terms of the usual accelerator physics concepts of emittance, energy spread, dispersions and betatron functions. In this way one can compare two BPM systems comparing their so-called error emittances and error energy spreads, or, for a given measurement system, one can achieve a balance between coordinate and momentum reconstruction errors by matching the error betatron functions in the point of interest to the desired values.

MOPD45	Single-Shot Beam Characterization Device Based on the Pepper-Pot Principle	ion, emittance, electron, permanent-magnet	155
	S.X. Peng, J.E. Chen, Z.Y. Guo, P.N. Lu, Z.X. Yuan, J. Zhao PKU/IHIP, Beijing, People's Republic of China H.T. Ren Graduate University, Chinese Academy of Sciences, Beijing, People's Republic of China
	Funding: National Nutural Science Foundation of China No.11075008 For the characterization of an ampere-scale microsecond single-pulse ion beam, a pepper-pot based beam profile measurement device was developed in PekingUniversity(PKU). It is a combination of Faraday cup technique with pepper-pot measurement facility. The direct Faraday cup is used to observe the total beam current and an array of pepper-pot diamond holes at the bottom of the Faraday cup is served to separate a large beam into several beamlets for beam distribution measurement. A Faraday array that locates 3.8 mm away from the pepper-pot screen is used to measure the transverse size of the beam. Two sets of permanent magnet poles that locate at the entrance of the Faraday cup and just before the Faraday array respectively are used to suppressing the second electrons produced by the interaction of the beam with target. In this paper we emphasize details of the experimental setup, the results of the measurements and we give an outlook on further developments on pepper-pot devices.

TUPD52	First Measurements with the Test Stand for Optical Beam Tomography	ion, vacuum, luminosity, photon	422
	C. Wagner, O. Meusel, U. Ratzinger, H. Reichau IAP, Frankfurt am Main, Germany
	A test stand for optical beam tomography was developed. As a new non-destructive beam-diagnostic system for high current ion beams, the test stand will be installed in the low energy beam transport section (LEBT) of the Frankfurt Neutron Source (FRANZ) behind the chopper system. The test stand consists of a rotatable vacuum chamber with a mounted CCD camera. The maximum rotation angle amounts to 270°. In a first phase the optical beam profile measurement and 3D density reconstruction is tested with a time independent 10 keV He beam. The measurements and performance of data processing algorithms are compared with the beam transport simulations. In a later phase the performance with time dependent beams (120 keV, 200 mA) at a repetition rate of 250 kHz and a duty cycle of 2.5% has to be evaluated. An overview of the first phase results is shown.
	Poster TUPD52 [13.501 MB]

Paper

Title

Other Keywords

Page

MOPD12

Expressing Properties of BPM Measurement System in Terms of Error Emittance and Error Twiss Parameters

emittance, betatron, FEL, focusing

62

V. Balandin, W. Decking, N. Golubeva
DESY, Hamburg, Germany

The determination of variations in the beam position and in the beam energy using BPM readings is one of the standard problems of accelerator physics. If the optical model of the beam line and BPM resolutions are known, the typical choice is to let jitter parameters be a solution of the weighted linear least squares problem. For transversely uncoupled motion this least squares problem can be solved analytically, but the direct usage of the obtained solution as a tool for designing a BPM measurement system is not straightforward. A better understanding of the nature of the problem is needed. In this paper we show that properties of the BPM measurement system can be described in terms of the usual accelerator physics concepts of emittance, energy spread, dispersions and betatron functions. In this way one can compare two BPM systems comparing their so-called error emittances and error energy spreads, or, for a given measurement system, one can achieve a balance between coordinate and momentum reconstruction errors by matching the error betatron functions in the point of interest to the desired values.

MOPD45

Single-Shot Beam Characterization Device Based on the Pepper-Pot Principle

ion, emittance, electron, permanent-magnet

155

S.X. Peng, J.E. Chen, Z.Y. Guo, P.N. Lu, Z.X. Yuan, J. Zhao
PKU/IHIP, Beijing, People's Republic of China
H.T. Ren
Graduate University, Chinese Academy of Sciences, Beijing, People's Republic of China

Funding: National Nutural Science Foundation of China No.11075008
For the characterization of an ampere-scale microsecond single-pulse ion beam, a pepper-pot based beam profile measurement device was developed in PekingUniversity(PKU). It is a combination of Faraday cup technique with pepper-pot measurement facility. The direct Faraday cup is used to observe the total beam current and an array of pepper-pot diamond holes at the bottom of the Faraday cup is served to separate a large beam into several beamlets for beam distribution measurement. A Faraday array that locates 3.8 mm away from the pepper-pot screen is used to measure the transverse size of the beam. Two sets of permanent magnet poles that locate at the entrance of the Faraday cup and just before the Faraday array respectively are used to suppressing the second electrons produced by the interaction of the beam with target. In this paper we emphasize details of the experimental setup, the results of the measurements and we give an outlook on further developments on pepper-pot devices.

TUPD52

First Measurements with the Test Stand for Optical Beam Tomography

ion, vacuum, luminosity, photon

422

C. Wagner, O. Meusel, U. Ratzinger, H. Reichau
IAP, Frankfurt am Main, Germany

A test stand for optical beam tomography was developed. As a new non-destructive beam-diagnostic system for high current ion beams, the test stand will be installed in the low energy beam transport section (LEBT) of the Frankfurt Neutron Source (FRANZ) behind the chopper system. The test stand consists of a rotatable vacuum chamber with a mounted CCD camera. The maximum rotation angle amounts to 270°. In a first phase the optical beam profile measurement and 3D density reconstruction is tested with a time independent 10 keV He beam. The measurements and performance of data processing algorithms are compared with the beam transport simulations. In a later phase the performance with time dependent beams (120 keV, 200 mA) at a repetition rate of 250 kHz and a duty cycle of 2.5% has to be evaluated. An overview of the first phase results is shown.

Poster TUPD52 [13.501 MB]