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Tapered glass capillary optics was utilized to produce MeV ion microbeams at the RIKEN Pelletron facility. A microbeam of 3 MeV He ions was used to irradiate HeLa cells and demonstrated an ion track consisting of double strand break points in the cell nucleus. A new microbeam line was developed with profile measurements of 2.8 MeV H+ microbeams in the atmosphere, using image recognition and knife-edge methods. After the suppression of the halo component in the microbeam, a smaller beam size was measured to be approximately 40 μm for the irradiation distance of 1 mm, which satisfied requirements of the planned applications.

We measured laser microbeam (18 µm) profiles of tilted glass capillary at wavelength 375 nm. The profile intensity, width and beam guided angle were obtained and results show guiding effect of the capillary optics.

The transmission of an ultraviolet-laser microbeam through a tapered glass capillary was investigated. We measured microbeam profiles using fluorescent beads and obtained smaller spots for smaller ...

High-resolution atomic-beam laser spectroscopy has been performed to study Stark effect of Ba atom. Stark spectra have been observed at various electric fields for Ba highly excited states. The scalar polarizability of the transition from 6s5d3D2 to 5d6p3F3 at 728.0 nm and the tensor polarizability of the 3F3 level have been determined for the first time, to be αs = -89.8 (12) kHz/(kV/cm)2 and αt = -133.7 (20) kHz/(kV/cm)2, respectively.

Propagation and transmission of laser beam through tapered glass capillary were investigated for light microbeams. Transmittances of laser light at 488 nm and 633 nm through capillaries were measured to be up to 15%, depending on outlet diameters. By modeling the real capillary, transmittances were calculated using taper angles obtained from shape analysis and agree well with experimental ones.

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.

The transmission of a laser beam through a tapered glass capillary was investigated both experimentally and theoretically for light microbeams. The transmittances of laser light at 488 and 633 nm through capillaries were measured to be up to 15%, depending on the outlet diameter. By characterizing a real capillary with precise measurement of the whole capillary geometry, a realistic simulation allowed us to calculate the transmittance. By using a Gaussian profile as the input beam in a simulation, the calculated transmittances well reproduced the experimental ones. The density enhancement of the extracted beam was derived and discussed.