TY  - JOUR
A1  - Jakob, Ansgar
A1  - Klein, Horst
A1  - Lakatos, Andreas
A1  - Meusel, Oliver
A1  - Pozimski, Jürgen
T1  - Investigation of the focus shift due to compensation process for low energy ion beam transport
T2  - Presented at the 7th EPAC Conference (Vienna, Austria 2000)
N2  - In magnetic Low Energy Beam Transport (LEBT) sections space charge compensation helps to enhance the transportable beam current and to reduce emittance growth due to space charge forces. For pulsed beams the time neccesary to establish space charge compensation is of great interest for beam transport. Particularly with regard to beam injection into the first accelerator section (e.g. RFQ) investigation of effects on shift of the beam focus due to space charge compensation are very important. The achieved results helps to obviate a mismatch into the first RFQ. To investigate the space charge compensation due to residual gas ionization, time resolved measurements using pulsed ion beams were performed at the LEBT system at the IAP and at the CEA-Saclay injektion line. A residual gas ion energy analyser (RGIA) equiped with a channeltron was used to measure the potential destribution as a function of time to estimate the rise time of compensation. For time resolved measurements (delta t min=50ns) of the radial density profile of the ion beam a CCD-camera was applied. The measured data were used in a numerical simulation of selfconsistant eqilibrium states of the beam plasma [1] to determine plasma parameters such as the density, the temperature, the kinetic and potential energy of the compensation electrons as a function of time. Measurements were done using focused proton beams (10keV, 2mA at IAP and 92keV, 62mA at CEA-Saclay) to get a better understanding of the influence of the compensation process. An interpretation of the acquired data and the achieved results will be presented.
Y1  - 2000
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/4097
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30-13884
UR  - http://accelconf.web.cern.ch/accelconf/e00/PAPERS/WEP3B06.pdf
ER  -