• D.E. Donets, E.D. Donets, E. E. Donets, V.V. Salnikov, V. B. Shutov, E. M. Syresin
  JINR, Dubna

Accelerated ¹²C ion beams are effectively used for cancer treatment at various medical centers, in particular to treat patients with radio resistant tumors. On the other hand, positron emission tomography is the most effective way of tumor diagnostics. The intensive ¹¹C ion beam could allow both these advantages to be combined. It could be used both for cancer treatment and for on-line positron emission tomography. Formation of a primary radioactive ¹¹C⁶⁺ ion beam with the intensity of 10¹⁰-10¹¹ pps from the ion source may allow cancer treatment and on-line dose verification. ¹¹C isotope is produced in the nuclear reaction ¹⁴N (p,α)¹¹C using the gas target chamber irradiated by a proton beam. If the nitrogen target chamber contains about 5% of hydrogen, approximately 10¹⁴ methane molecules ¹¹CH₄ can be produced each 20 minutes. The separated radioactive methane can be loaded into an ion source. The methodology and technique of formation of high-intensity radioactive carbon beams were tested in the JINR electron string ion source (ESIS) Krion-2 using usual non radioactive methane. The measured conversion efficiency of methane molecules to carbon ions appeared to be rather high, 15 % for C⁶⁺ ions and 25% for C⁴⁺ ions. The developed technique of pulsed methane loading and the experimentally obtained conversion efficiency permit obtaining primary radioactive ¹¹C⁶⁺ beams at the intensity of 10¹⁰ -10¹¹ pps and performing cancer treatment and online dose verification.

• D. E. Donets, E. D. Donets, E. E. Donets, V.M. Drobin, A.V. Shabunov, Yu. A. Shishov, V.B. Shutov, E.M. Syresin
  JINR, Dubna
• A.E. Dubinov, R.M. Garipov, I.V. Makarov
  VNIIEF, Sarov

The so-called reflex mode of Electron String Ion Source (ESIS) operation has been under intense study, both experimental and theoretical at JINR during the last decade. The idea of using a tubular electron string ion source (TESIS) has been put forward recently to obtain 1- 2 orders of magnitude increase in the ion output as compared with ESIS. The project is aimed at creating TESIS and studying an electron string in the tubular geometry. The new tubular source with a superconducting solenoid up to 5 T should be constructed in 2010. The method of the off-axis TESIS ion extraction will be used to get TESIS beam emittance comparable with ESIS emittance. It is expected that this new TESIS (Krion T1) will meet all rigid conceptual and technological requirements and should provide an ion output approaching 10 mA of Ar¹⁶⁺ ions in the pulse mode and about 10 μA of Ar¹⁶⁺ ions in the average current mode. Analytical, numerical study of the tubular electron strings and the design of the TESIS construction are given in this report. The experiments with quasi tubular electron beams performed on the modified ESIS Krion 2 are also discussed there.

• Y. Kato, T. Iida, F. Sato
  Osaka Univ., Suita

An electron cyclotron resonance ion source (ECRIS) has been developing long time and their performance is still extending at present. Recently, they are not only used in producing multi-charged ions, but also molecules and cluster ions. A new type of ion source with a wide operation window is expected for various uses. We developed a novel magnetic field configuration ECRIS. The magnetic field configuration is constructed by a pair of comb-shaped magnetic field by all permanent magnets and has opposite polarity each other with ring-magnets. This magnetic configuration suppresses the loss due to E×B drift, and then plasma confinement is enhanced. We conduct preliminary extracting and forming large bore ion beam from this source. We will make this source a part of tandem type ion source for the first stage. Broad ion beams extracted from the first stage and transfer like a shower to plasma generated by the second stage. We hope to realize a device which has a very wide range operation window in a single device to produce many kinds of ion beams. We try to control plasma parameters by multiply frequency microwaves for broad ion beam extraction. It is found that plasma and beam can be controllable on spatial profiles beyond wide operation window of plasma parameters. We investigated feasibility of the device which has wide range operation window in a single device to produce many kinds of ion beams as like universal source based on ECRIS.

• S.A. Cherenshchykov
  NSC/KIPT, Kharkov

New properties of vacuum discharges in magnetic field with unconventional discharge gaps at low pressure up to high vacuum are briefly described. Both single- and multi-charge ion sources may be developed on basis of such new discharge modes. Such ion sources may have advantages in comparison with conventional ones. The main advantages are the long lifetime due to the absence of filaments and arc spots, high energy and gas efficiency due to high plasma electron temperature. The development of the discharge research and recent results are discussed.

• A. Galatà, L. Bertazzo, L. Boscagli, S. Contran, A. Dainese, A. Facco, A. Lombardi, D. Maniero, M. Poggi, M. Sattin, F. Scarpa
  INFN/LNL, Legnaro
• T. Kulevoy
  ITEP, Moscow

The positive ion injector for the PIAVE-ALPI complex consists of an ECR ion source placed on a high voltage platform. A 14.4 GHz ECRIS named Alice, designed and constructed at LNL in the early &##8216;90, reliably delivered gaseous beams to the Superconducting RFQ PIAVE for nuclear physics experiments until 2008. The requests for heavy ion beams of increased current and energy, needed to perform the experiments planned for the next years with the AGATA demonstrator, prompted us to upgrade our injector with a new ECR source capable of higher output beam currents and higher charge states. This activity started in 2008 and was completed at the beginning of 2009. A 14.5 GHz, SUPERNANOGAN type ECRIS built by Pantechnik, was installed in our refurbished high voltage platform in July 2008. The space available for maintenance in the platform was increased and a new lead shielding for X-rays has been set up. The water cooling circuits have been redesigned to deliver different fluxes and inlet pressures to the equipment mounted on the platform (plasma chamber, extraction electrodes, bending dipole and power supply). A new safety system has been implemented in order to cope with new and more demanding safety rules. A lot of attention has been paid to the optimisation of the injection line with new diagnostic devices for beam characterisation (movable slits, emittance measurement tools). Commissioning of the new source and injector with beams has started and first results will be reported.

• M. Cavenago, M. Comunian, E. Fagotti, M. Poggi
  INFN/LNL, Legnaro
• T. Kulevoy, S. Petrenko
  ITEP, Moscow

Singly charged ion sources can easily surpass the 1 kW beam power, as in TRIPS (H⁺, 60 mA, 80 kV, now installed at LNL) or in NIO1 (H^-, 130 mA distributed into 9 beamlets, 60 kV, a project of RFX and INFN-LNL). Beam diagnostic constitutes an important instrument in the high current source development. Even if calorimetric and optical beam profile monitors become possible, still a phase space plot of the beam will be the most useful tool for validation of extraction simulation and for input of subsequent beam transport optimization. Improvements in extraction beam simulations are briefly reported, and effect of space charge neutralization is discussed. Since preliminary design of the traditional two moving slit beam emittance meter show problems with slit deformations and tolerances and with secondary emission, an Allison scanner was chosen with the advantages: only one movement is needed; data acquisition is serial and signal can have an adequate suppression of secondary electrons. The design of a compact Allison scanner head is discussed in detail, showing: 1) the parameter optimization; 2) the segmented construction of electrodes. Experimental commissioning at lower power seems advisable.