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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

The high-resolution ultraviolet (UV) laser spectroscopy of 27Al has been performed by the frequency doubling of a tunable diode-laser beam together with a collimated atomic beam. Hyperfine structure spectra have been observed for two UV transitions in Al I, namely, 3s23 p2P1/2–3s24s2S1/2 at 394.401 nm and 3s23 p2P3/2–3s24s2S1/2 at 396.152 nm. The hyperfine structure constants A and B of 27Al have been determined for the 3s23 p2P1/2,3/2 and 3s24s2S1/2 levels, and compared with previously reported results.

High-resolution laser spectroscopy has been performed using a tunable diode laser to measure the hyperfine structure (hfs) and Zeeman shift of two transitions in Y I. The hfs constants A of 89Y were determined for the 4d5s 2 2 D 3/2 and 2 D 5/2 levels, and 4d5s5p 4 F 3/2 and 4 F 5/2 levels; the A values of the 4 F 3/2 and 4 F 5/2 were determined for the first time. Using circular polarizations, the Zeeman spectra were selectively measured and the g factors were determined for the 4d5s5p 4 F 3/2 and 4 F 5/2 levels.

The lithium ion beam was neutralized in a newly developed charge-exchange cell. The charge exchange was performed with sodium, lithium and iron vapors. The lithium atom was photoionized in a three-step resonance-ionization scheme where the first-step excitation was performed with a cw external-cavity diode laser. The resonance ionization with a diode laser and a pulsed dye laser was as efficient as that with two high-power pulsed dye lasers.

Combined with a collimated atomic beam source, diode laser without external cavity has been used as a spectroscopic light source to study atomic hyperfine structures and isotope shifts of Ba i. Spectroscopic measurements of the 6s 2 1 S 0 – 6s6p 3 P 1 transition of Ba i have been carried out. All hyperfine peaks of 135,137Ba have been clearly seen and resolution of 50 MHz has been attained. Hyperfine constants A and B of the 3 P 1 state of 135,137Ba have been determined. Isotope shifts of stable Ba isotopes have also been measured. From the measured isotope shifts, the 6s electron density at the nucleus has been deduced to be 76.4(53) a.u. and discussed in terms of the Hartree-Fock approximation.

An atomic beam oven of a discharge type is constructed and the performance in populating a metastable state of Yb I is examined. The relative populations of the ground state 4f 146s 21 S 0 and the metastable state 4f 135d6s 2 (7/2, 3/2)5 of Yb I are measured for the first time by the laser-induced fluorescence method. It is found that the population of the metastable state increases with the discharge current and that of the ground state decreases to 30%. The method is also applicable for other elements.