Conveners
O4
- Mamiko Sasao (Doshisha University)
- Katsuyoshi Tsumori (National Institute for Fusion Science)
Abstract. The Japan Proton Accelerator Research Complex (J-PARC) cesiated RF-driven Hˉ ion source has been stably operated for about six years. The J-PARC 400 MeV LINAC successfully accelerated the 60 mA beam required for the J-PARC, when a 72 mA beam was injected from the source. The high intensity beam with transverse emittances suitable for the RFQ is produced with several unique measures,...
Oscillation of emittance and Twiss parameters in the negative ion $(\text{H}^-)$ beam from the J-PARC 2MHz RF ion source is measured by applications of a double-slit emittance monitor located at the RFQ (Radio Frequency Quadrupole) entrance. The emittance monitor is equipped with a newly-developed 60 MS/s data acquisition system, so that beam current oscillation in a few MHz can be observed...
The multi-cusp negative ion source with a unique end-plug, so-called Eclair ion source, has been designed for high power negative ion sources required in fusion devices such as ITER and JT-60SA. This Eclair ion source shows one of the ideal magnetic field configurations designed by the detailed fast electron analysis to achieve both uniform negative ion production and reduction of a...
Diagnostics at the region between magnetic filter to plasma grid of negative ion sources are important to understand the mechanism of the process through production to extraction of negative ions in source plasmas seeded caesium (Cs). Millimeter microwave interferometry and cavity ringdown (CRD) measurement are reliable diagnostic methods to measure line-averaged densities of electrons and...
For injection into a tandem accelerator of the BNCT device at Budker INP, Novosibirsk, a steady-state charge-exchange negative ion source with a current of ~ 10 mA is being developed. The primary beam of hydrogen ions with a current of 1–2 A and an energy of 30 keV is formed by a an RF ion source using a multi-aperture four-electrode ion-optical system with ballistic focusing. The RF plasma...
A continuous-wave surface-plasma negative hydrogen ion source is used to inject a negative ion beam into tandem accelerator with vacuum insulation at Budker Institute of Nuclear Physics since 2006. In the ion source, Penning discharge with plasma injection from hollow cathodes and cesium seeding is applied to generate a negative ion beam with a current up to 10 mA at 25 KV acceleration...
A high-voltage negative ion based neutral beam injector is under construction at the Budker Institute of Nuclear Physics [1]. It consists of the negative ion source, of the low-energy beam transport section (LEBT) to purify the beam before the acceleration, of the multi-electrode single-aperture beam accelerator and of the plasma neutralizer and beam magnetic separator with beam energy...
Negative Ion based inductively coupled plasma sources operate in a high RF power and HV environment for plasma production and beam transport. Due to plasma power coupling dynamics, RF power mismatch causes large reflected fields which affect all the diagnostic signals by degrading the signal to noise ratio. In addition to RF disturbances, during the beam extraction and acceleration, the...
In the present work, a deep learning model is developed for a permanent magnet-based helicon plasma source. The non-invasive cavity ring-down spectroscopy (CRDS) characterizes the HELEN ion source as a negative hydrogen ion source. This paper discusses different deep learning techniques for modelling the ion source and subsequently predicts the ion source density. The experiments were...
ROBIN [1] is a single RF driver based negative ion test bed currently in operation at IPR, Gandhinagar, India. To understand and have deeper insights of physical phenomenon, several diagnostics have been interfaced with ROBIN system.
To quantify the negative ion density in ROBIN source, laser photo detachment (LPD) diagnostic is configured. LPD at ROBIN is based on single high power Nd:YAG...
