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ion sourceWada, Motoi*; Shinto, Katsuhiro; Shibata, Takanori*; Sasao, Mamiko*
Review of Scientific Instruments, 91(1), p.013330_1 - 013330_5, 2020/01
Times Cited Count：0 Percentile：100(Instruments & Instrumentation)The ions are extracted from an ion source through a plasma sheath where a low frequency electromagnetic induction drives transport of charged particles including the target ions. High frequency alternating current commonly excites plasmas in sources for negative hydrogen (H) ions at a frequency in the MHz range. A high-speed beam current monitor system coupled to a narrow entrance slit enabled the investigation of the special distribution of the AC component intensity of the H ion beam extracted from an ion source driven by a 2 MHz radio frequency (RF) power. The distribution showed a smaller oscillation of the beam at the center.
Shinto, Katsuhiro; Okoshi, Kiyonori; Shibata, Takanori*; Nammo, Kesao*; Ikegami, Kiyoshi*; Takagi, Akira*; Namekawa, Yuya*; Ueno, Akira; Oguri, Hidetomo
AIP Conference Proceedings 2052, p.050002_1 - 050002_7, 2018/12
Times Cited Count：2 Percentile：9.99In the 2017/2018 campaign, the J-PARC cesiated rf-driven negative hydrogen (H) ion source producing H beam with the beam current of 47 mA accomplished three long-term operations more than 2,000 hours without any serious issues. On the final day of this campaign, the ion source produced an H beam current of 72 mA so that the linac commissioning group could demonstrate the beam current of 60 mA at the linac exit. We are also conducting an endurance test of a J-PARC-made antenna at a test bench. The antenna achieved the operation time approximately 1,400 hours.
ion sourceShinto, Katsuhiro; Okoshi, Kiyonori; Ikegami, Kiyoshi*; Takagi, Akira*; Shibata, Takanori*; Nammo, Kesao*; Namekawa, Yuya*; Ueno, Akira; Oguri, Hidetomo
AIP Conference Proceedings 2011, p.050018_1 - 050018_3, 2018/09
Times Cited Count：3 Percentile：4.6 ion sourceShinto, Katsuhiro; Shibata, Takanori*; Miura, Akihiko; Miyao, Tomoaki*; Wada, Motoi*
AIP Conference Proceedings 2011, p.080016_1 - 080016_3, 2018/09
Times Cited Count：3 Percentile：4.6Shibata, Takanori*; Shinto, Katsuhiro; Takagi, Akira*; Oguri, Hidetomo; Ikegami, Kiyoshi*; Okoshi, Kiyonori; Nammo, Kesao*; Naito, Fujio*
AIP Conference Proceedings 2011, p.020008_1 - 020008_3, 2018/09
Times Cited Count：4 Percentile：2.43Shinto, Katsuhiro
Kasokuki, 14(4), p.248 - 250, 2018/01
The 17th International Conference on Ion Sources (ICIS 2017) was held on 15th - 20th October 2017 at Geneva in Switzerland. This conference is held biennially. Most of scientists and engineers for ion sources in the world meet at the conference in order to share results of research and development.
ion source upon the extracted beamShinto, Katsuhiro; Shibata, Takanori*; Wada, Motoi*
Proceedings of 14th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.648 - 650, 2017/12
In J-PARC, peak H current of several tens mA is extracted from an ion source driven by a solid-state rf amplifier with the frequency of 2 MHz for production of a cesiated hydrogen plasma. In case of the rf-driven ion source for producing the high-intensity H current, the plasma density in the source chamber is so high that the ion sheath around the beam extraction area can follow the rf oscillation. The H beam current fluctuation as large as approximately 1 mA was observed at the average beam current of 44 mA measured by a Faraday cup installed downstream of the ion source. The beam exhibited some fluctuation to the transverse motion as well. To further clarify this high frequency oscillation of the beam extraction sheath, we propose a measurement system using a time-resolved and highly sensitive emittance monitor in order to observe the real-time beam fluctuation in the phase space.
beam extracted from a high-intensity rf-driven H ion sourceShinto, Katsuhiro
no journal, ,
no abstracts in English
ion source upon the extracted beamShinto, Katsuhiro
no journal, ,
no abstracts in English
ion sourceShibata, Takanori*; Takagi, Akira*; Shinto, Katsuhiro; Ikegami, Kiyoshi*; Okoshi, Kiyonori; Nammo, Kesao*; Oguri, Hidetomo; Naito, Fujio*
no journal, ,
For the application of bias voltage in J-PARC Radio Frequency (RF) negative ion source, characteristics of the voltage variation on the plasma electrode are investigated with different RF plasma conditions. A continuous 30 MHz RF power up to 10 - 100 W and a pulsed 2 MHz RF power up to 5 - 20 kW are injected from internal RF antenna coil. In each case, time structure of the voltage between the plasma electrode and the isolated source chamber is measured by voltage probe with different measurement resistances. Behavior of the measured voltage differs strongly whether the RF plasma is in the E mode phase by 30 MHz RF injection or in the H mode phase by 2 MHz RF injection. The results suggest that formation of capacitively coupled electric field and inductively coupled magnetic field decide the positive and the negative fluxes coming into the chamber wall. Under the same plasma condition as in the J-PARC user operation, peak value of the voltage between the source chamber and the plasma electrode is around 60 - 80 V and frequency of the voltage is a combination of 2 MHz and 30 MHz. For the continuous bias voltage application on the plasma electrode, additional distributed constant circuit to cancel these voltage oscillation and high voltage bias power supply are required.
