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Synopsis Profiles of 2.8 MeV H+ microbeam extracted from a single tapered glass capillary optics were meas-ured by two methods for a future irradiation to an outer organ of insect target. The halo component was analyzed to be 575 μm in full width at half maximum (FWHM) at a plastic tracking detector CR-39 located 1 mm down-stream of the capillary. The core component was examined by knife-edge method according to the ion energies. The profiles consisting of more energy-loss events have wider FWHM, which can be reduced by Al thin layers.

We have developed a method to produce a nm sized slow highly-charged ion beam based on a self-organized charge up inside a single tapered-glass capillary. In order to investigate the characteristics of the obtained beams, the transmission of 8 keV Ar8+ beam through the capillary of 5-cm long with 800/24 μm inlet/outlet inner diameter was examined. The transmitted beam had the same size as the outlet with the beam-density enhancement of approximately 10. The initial beam was guided through a capillary tilted by as large as ±100 mrad and it still kept the incident charge. A focused ion beam of Ga+ was employed to manufacture the capillary outlet as small as several hundreds nm in diameter and fabricate a thin glass window at the capillary outlet for biological applications.

This year, a prototype of a highly sensitive beam current monitor with a High- Temperature Superconducting (HTS) SQUID and an HTS magnetic shield: HTS-SQUID monitor has been installed in the beam transport line of the RIKEN Ring Cyclotron (RRC). Unlike other existing facilities, the HTS-SQUID monitor allows us to measure the DC of highenergy heavy-ion beams nondestructively in such a way that the beams are diagnosed in real - time and the beam current extracted from the RRC can be recorded without interrupting the beam user's experiments.

An estimation method of micro-meter sized laser profile created by the laser beam transmission through a tapered glass capillary is developed for the target sight-on system of ion microbeam irradiation to living cells. In our system, both the laser and the ions are designed to be transmitted through the same capillary so that the laser spot is surely on the ion track. By selecting the excitation light of a fluorescent protein in cell nucleus, the fluorescent volume can be confirmed as the targeted area.

Towards production of microbeams, propagation of laser beams of visible light with wavelengths of 488, 633 and 670 nm through tapered glass capillaries has been studied. In conjunction with an optical lens upstream of the capillaries with outlet sizes ranging from 17 to 100 μm, transmission efficiency more than 80% has been achieved for outlet diameters more than 40 μm

We have developed a method to produce micrometer-sized beams of keV energy highly charged ions (HCIs) and MeV energy protons/helium ions with tapered glass capillary optics for the applications of micrometer sized surface modifications and a biological tool, respectively. The transmission experiments of keV HCIs through the glass capillaries show a density enhancement of about 10, beam guiding up to 5°, and the extracted beam keeping the initial charge-state. The combination of MeV ion beams and the capillary with a thin end window at its outlet was used for the irradiation of a part of nucleus of a HeLa cell in culture solution. Escherichia coli cells are irradiated by MeV proton microbeam to determine the minimum dose to stop the single flagellar motor. Scanning irradiation of polymer surface by the beam extracted from the capillary in solution containing acrylic acid was found to provide a deposition layer with large affinity with water.

Microbeams of MeV ions focused through tapered glass capillaries with end-windows have been used for the irradiation of small volume (order of 1μm) inside living cells cultivated in liquid medium. In order to control the dose with accuracy of about 1 MeV, single ion irradiation and its counting method are required. We propose here the possibility of single ion counting by using glass capillaries with plastic scintillator end-windows.

We have studied the properties of guiding of Ne7+ ions through nanocapillaries in insulating PET polymers for incident energies from 3.5 to 7 keV with a two-dimensional position sensitive detector. During the intensity evolution of transmitted ions, the deflection angle of the transmitted Ne7+ ions shows a few oscillations before approaching an equilibrium value. The experimental results are interpreted in terms of a scenario where the deflection angles of transmitted ions are governed by charge patches formed on the inner wall of the capillary. In addition, the memory effect of charge patches retained from previous irradiation are studied.

Two years ago, a prototype of a highly sensitive beam current monitor with a high-temperature superconducting (HTS) SQUID, an HTS current sensor and an HTS magnetic shield, that is, an HTS-SQUID monitor, was installed in the beam transport line of the RIKEN ring cyclotron (RRC). As a result, the beam intensity of a sub-μA beam was successfully measured by the prototype HTS-SQUID monitor. In fact, the intensity of a sub-μA 40Ar15+ (63 MeV/u) beam was successfully measured with a 500 nA resolution. However, the current resolution of the prototype HTS-SQUID monitor is not sufficient to measure the current of a uranium beam, which is accelerated in a new radioactive isotope (RI) beam facility called "RI Beam Factory" (RIBF). A minimum current resolution of 1 nA is required for the measurement of the uranium beam. Therefore, we are developing a new HTS-SQUID monitor so as to improve the current resolution. This new monitor consists of three parts, the HTS SQUID, an HTS current sensor and an HTS magnetic shield, and these parts have been separately developed this year. The high-permeability core that is installed in the two input coils of the HTS-SQUID is an extremely important part in this new HTS-SQUID monitor. A 50-fold improvement in gain was successfully realized using the high-permeability core compared with that obtained without the high-permeability core. Another key factor is the substrate of the HTS current sensor. A MgO ceramic tube was used for the substrate of the HTS current sensor in the prototype HTS-SQUID monitor. However, it was difficult to form the bridge circuit using the MgO ceramic substrate in the new HTS-SQUID monitor, because the bridge circuit that magnetically connects the HTS current sensor and the HTS-SQUID has to be three-dimensional. To solve this problem, silver (Ag) of 99.9% purity was adopted for the substrates of the HTS current sensor in the new HTS-SQUID monitor. Then the surfaces of the substrates were coated by a thin layer (70μm) of Bi2-Sr2-Ca1-Cu2-Ox (Bi 2212), which is an HTS material. We report the results of this development.

We have developed methods to focus slow highly charged ions, MeV ions, and muon beams with various glass-made beam optics. (1) A focusing effect for an Ar8 + beam of 8 keV through a cm-long tapered capillary was obtained with a density enhancement of the transmitted beam compared with that of the input beam, which increases from 1 to 6 as the input current decreases from 30 pA to 0.8 pA. To study the stability of the transmitted beams through a glass capillary, we have measured the transmission of an 104 keV Ar8+ beam through a gap between a pair of parallel glass plates, and observed a precisely vibrational output current. (2) For 4 MeV He2+ beam, a 100 times density enhanced beam by a cm-long tapered capillary with a closed outlet was utilized to irradiate a cell in liquid. The range of the beam was controlled by the closed outlet with accuracy of ~1 μm. (3) Using 40 cm-long tapered glass tubes, a density enhancement of a factor of 2 was observed for both positive and negative muon beams with an energy of 13 MeV.