[en] A classical type two stage 6.4 GHz ECR heavy ion source that was developed a few years ago, has undergone several modifications based on magnetic topological compactness, external supply of cold electrons and microwave feed to improve the performance. At present, it is an electron repeller driven single stage ECR ion source capable of delivering more than 100 eμA of O⁵⁺ beam. A study had been carried out to understand the dramatic improvement already achieved

[en] Of the various types of ion sources, Electron Cyclotron Resonance (ECR) ion source is the most frequently used heavy ion source for cyclotrons. The objective of the present development is to provide remote monitoring and control of the operation of a set of power supplies through a user-friendly human-computer interface (HCI). A brief description of the system is presented in this paper

[en] The 6.4 GHz ECR ion source that was indigenously developed a few years ago has been operating continuously for injecting oxygen and neon beams to the cyclotron since 1997. VEC-ECR is a single stage high magnetic field ion source provided with a negatively biased electron repeller placed on the axis, near the injection mirror point. The supply of cold electrons and use of low mass mixing gas improve the stability of ECR plasma. Very recently, the effect of aluminium oxide coating on the copper plasma chamber wall has been studied. The plasma chamber wall was coated with aluminium by vacuum evaporation method and then exposed to oxygen gas to form aluminium oxide. It was noticed that the process substantially shifts the charge state distribution to the higher charge state with an enhancement of ion current by an order of magnitude. With the aluminized plasma chamber, the VEC-ECR can now produce 12 μA of O⁷⁺, 6.5 μA of Ar¹²⁺, 1.5 μA of Kr²⁰⁺ and 1.0 μA of Xe³¹⁺. (author)

[en] An Electron Cyclotron Resonance (ECR) heavy ion source, basically a hot electron plasma machine having B-minimum field configuration is going to be operational soon at this centre. The source which is indigenously built will act as a heavy ion injector for the Variable Energy Cyclotron (VEC) replacing the existing penning (PIG) internal light ion source. This programme was undertaken to facilitate acceleration of multiply charged heavy ions (MCHI) in the cyclotron. The heavy ions, substantially energetic compared to the light ions will be utilised to initiate new fields of research with heavy ions. The present ECR source is expected to produce fully stripped light heavy ions and partially stripped heavy ions. It will be suitable for metallic ions also. Radio frequency (rf) power is transferred to the ionising electrons in this source at a frequency in resonance with the electron cyclotron frequency (ECR). VEC ECR source is a two stage, room temperature heavy ion source, Stage-1 acts as an injector for the Stage-2, the main stripping stage which has a B-minimum magnetic field configuration. Powerful samarium-cobalt sextupolar permanent magnet generates the radial field of the second stage. The resonance frequency of operation is same for both stages and is 6.4 GHz. Two commercially available 6.4 GHz, 3 Kw microwave generators have been procured to supply the rf power. The source has been partly assembled in the ECRIS laboratory of VECC. A vacuum of 1 x 10^-7 torr in the source and 5x10^-8 torr in the analysing line have been obtained. A charge analysing system comprising two 45deg normal entry and normal exit dipoles and four quadrupoles (QDQ QDQ System) has been built. The fabrication work of entire injection line comprising optical elements, beam transport lines, radio frequency buncher, beam inflector, etc. coming in the phase-2 programme shall start immediately after the source commissioning. (author). 11 refs., 5 figs., 2 tabs

[en] Short communication. 3 refs., 3 figs

[en] Sulphur ion beam has been produced recently from the 6.4 GHz single stage min-B ECR ion source at VECC. This multiply charged heavy ion source has been operating continuously for injecting beams into the cyclotron. We find a little time to carry out further development work on this dedicated ion source. So, the essential development has always been done on a test set-up before incorporating the actual change into the source

[en] An indigenously developed 6.4 GHz ECR ion source has been operating continuously for injecting multiply charged heavy ion beam into the cyclotron. At present, VEC-ECR is a single stage min-B ECR ion source with a negatively biased electron repeller placed on the axis, near the injector mirror point

[en] Residual gas analysis with the help of a quadrupole residual gas analyser (QRGA) has been utilised to diagnose various problems which cause hindrance to achieve proper vacuum conditions in the cyclotron. These problems include air leakage, water leakage, freon leakage from baffle and oil vapour contamination. 7 figures. (author)

[en] The first indigenous Electron Cyclotron Resonance (ECR) Ion Source was developed in VECC in 1991 for injecting heavy ions into VEC to facilitate heavy ion acceleration. Preliminary performance of the source was quite satisfactory. To meet the pressing demand for intense stable Multiply Charged Heavy Ions (MCHI) VEC-ECR was modified for higher MCHI production efficiency. Several systematic studies were carried out for performance optimization. Since 1998, it is dedicated to inject oxygen, neon and nitrogen beams to the cyclotron. (author)

[en] In this work we have studied the energy gain of electrons in various multipole ECR traps in order to compare the relative advantages of various multipole magnetic fields