CYCLOTRONS 2010 - List of Authors (Tarvainen, O.A.)

Paper	Title	Page
MOPCP049	Ion Source Related Research Work at JYFL	150
	H. A. Koivisto, V.P. Aho, J.E. Ärje, T. Kalvas, J.A. Kauppinen, J.P. Kommpula, T. Ropponen, O.A. Tarvainen, V.A. Toivanen JYFL, Jyväskylä, Finland
	In this article the work of the JYFL ion source group will be presented. New bremsstrahlung measurements were carried out in order to compare the results with different electron heating models, especially defining the endpoint energy of the bremsstrahlung spectra. A project to obtain new information about the ion temperatures and their time evolution has been initiated. The study will be performed using spectroscopic techniques measuring the ion temperature through the Doppler broadening of emission lines. The objective is to reveal accurate information about the time evolution of highly charged ions in the ECRIS plasma. The work also includes frequency tuning experiments, beam quality experiments and tests with a so-called collar structure. The beneficial effect of collar was first tested and noticed with the ECR ion sources by the KVI ion source group and has been shortly confirmed at JYFL in collaboration with the KVI research group. The JYFL ion source group is also developing a low energy electron gun for the spacecraft applications. The results of the development work can possibly be applied also with the ion sources in order to increase the density of cold electrons.

MOPCP050	Studies of ECRIS Ion Beam Formation and Quality at the Department of Physics, University of Jyväskylä	153
	V.A. Toivanen, V.P. Aho, J.E. Ärje, J.A. Kauppinen, H. A. Koivisto, O.A. Tarvainen JYFL, Jyväskylä, Finland L. Celona, G. Ciavola, S. Gammino, D. Mascali INFN/LNS, Catania, Italy A. Galatà INFN/LNL, Legnaro (PD), Italy T. Ropponen NSCL, East Lansing, Michigan, USA
	During the last couple of years a lot of effort has been put into studies concerning the ion beam formation and beam quality of electron cyclotron resonance ion sources (ECRISs) at the Department of Physics, University of Jyväskylä (JYFL). The effects of microwave frequency fine tuning on the performance of JYFL 14 GHz ECRIS have been studied with multiple experiments in collaboration with INFN-LNS (Instituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud). Also, a number of measurements have been carried out to study the effects of space charge compensation of ion beams on the beam quality. In order to proceed further with these studies, a modified version of the beam potential measurement device developed at LBNL (Lawrence Berkeley National Laboratory) is under development. Simulations are used to study the possibility to improve the beam quality by biasing the beginning of the beam line upstream from m/q separation. With high voltage biasing the beam energy could be increased temporarily over the limit of the injection system of the accelerator. Latest results and current status of these projects will be presented and discussed.

Paper

Title

Page

Ion Source Related Research Work at JYFL

150

H. A. Koivisto, V.P. Aho, J.E. Ärje, T. Kalvas, J.A. Kauppinen, J.P. Kommpula, T. Ropponen, O.A. Tarvainen, V.A. Toivanen
JYFL, Jyväskylä, Finland

In this article the work of the JYFL ion source group will be presented. New bremsstrahlung measurements were carried out in order to compare the results with different electron heating models, especially defining the endpoint energy of the bremsstrahlung spectra. A project to obtain new information about the ion temperatures and their time evolution has been initiated. The study will be performed using spectroscopic techniques measuring the ion temperature through the Doppler broadening of emission lines. The objective is to reveal accurate information about the time evolution of highly charged ions in the ECRIS plasma. The work also includes frequency tuning experiments, beam quality experiments and tests with a so-called collar structure. The beneficial effect of collar was first tested and noticed with the ECR ion sources by the KVI ion source group and has been shortly confirmed at JYFL in collaboration with the KVI research group. The JYFL ion source group is also developing a low energy electron gun for the spacecraft applications. The results of the development work can possibly be applied also with the ion sources in order to increase the density of cold electrons.

MOPCP050

Studies of ECRIS Ion Beam Formation and Quality at the Department of Physics, University of Jyväskylä

153

V.A. Toivanen, V.P. Aho, J.E. Ärje, J.A. Kauppinen, H. A. Koivisto, O.A. Tarvainen
JYFL, Jyväskylä, Finland
L. Celona, G. Ciavola, S. Gammino, D. Mascali
INFN/LNS, Catania, Italy
A. Galatà
INFN/LNL, Legnaro (PD), Italy
T. Ropponen
NSCL, East Lansing, Michigan, USA

During the last couple of years a lot of effort has been put into studies concerning the ion beam formation and beam quality of electron cyclotron resonance ion sources (ECRISs) at the Department of Physics, University of Jyväskylä (JYFL). The effects of microwave frequency fine tuning on the performance of JYFL 14 GHz ECRIS have been studied with multiple experiments in collaboration with INFN-LNS (Instituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud). Also, a number of measurements have been carried out to study the effects of space charge compensation of ion beams on the beam quality. In order to proceed further with these studies, a modified version of the beam potential measurement device developed at LBNL (Lawrence Berkeley National Laboratory) is under development. Simulations are used to study the possibility to improve the beam quality by biasing the beginning of the beam line upstream from m/q separation. With high voltage biasing the beam energy could be increased temporarily over the limit of the injection system of the accelerator. Latest results and current status of these projects will be presented and discussed.