The Ni-like and Co-like X-rays emitted from laser produced Tin plasmas generated using the 1.06 µm, 1.2 ns pulses from a Nd:YAG laser were modelled. The modelling includes the Ni-like and Co-like X-ray resonance line spectrum emitted from Sn plasma between 12Å -25Å and also free-free and free-bound continuous spectrum emitted from the Zn-, Cu-, Ni-, Co-and Fe-like ions between 1Å and 30Å. Then, X-ray conversion efficiencies were calculated using these spectra. Maximum X-ray conversion efficiency was obtained 3.54 % at power density of 5 × 10 12 W cm −2 into 2π steradian. X-ray pulse durations were calculated spectrally integrated total X-ray emission of the Ni-like and Co-like from Sn plasmas.

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Ni-like and Co-like X-ray resonance line spectra are simulated between 16Å and 32Å emitted from silver plasma using Nd:YAG laser and its second, third and fourth harmonics for double pulse configurations. In addition to spectral lines, X-ray intensities obtained from free-bound and free-free continuum emission from Zn-, Cu-, Ni-, Coand Fe-like ions are calculated between 1Å and 30Å. The intensity for 280 ps prepulse is 5.4 × 10 12 W/cm 2 and for 1.2 ps short pulse is 4.4 × 10 15 W/cm 2 . The time difference between pre-pulse and short pulse is varied between 150 ps and 750 ps. X-ray energy conversion efficiencies and X-ray pulse durations are calculated from X-ray spectra. For example, maximum X-ray energy conversion efficiency for 750 ps time difference is obtained as 0.54 % for fundamental harmonic Nd:YAG laser, 1.01 % for second harmonic, 1.46 % for third harmonic, 1.86 % for fourth harmonic over 2π sr. The ratio of Co-like 3d → 4f and Ni-like 3d → 4f resonance line intensities is calculated to determine electron temperature.

Purpose: The purposes of this study were to measure the dose distribution of Photodynamic therapy(PDT) laser with 635 nm wavelength using GafChromic film. Method & Result: We made each output 300 J by changing mW and sec using the laser beam radiation mode such as C.W(Continuous Wave) mode, Pulse mode and Burst Pulse mode and measured the does at 0 mm and 5 mm of distance from optic fiber catheter end to the film, and at 5 mm distance by changing the angle of the end of the optic fiber catheter as 0 o and 0.5 o . The radiated film was scanned and OD(Optical Density) was compared. And two-dimensional isodose curves were obtained and the consistency of shapes was compared. It was confirmed that there was consistency between optic density and the dose radiated on the film when we radiated GafChromic film by changing distance and angle of 300 J output in each radiation mode coordinating mW and sec. Conclusion: In this study, we could identify the stability according to changes in laser beam modes, changes in output according to distance, changes in uniformity according to angle, and beam profiles using GafChromic film, and we could also get two-dimensional isodose curve. It was found that small change in the distance and angle that is made when optic fiber catheter was contacted on the treatment area did not make big effects on the output of beam and the uniformity of dose, and it was also found that GafChromic film could be utilized for the purpose of QA of PDT laser beam.

Increased interest in lasers and their industrial and photonics applications found a great support in Turkey from industry and govermental Agencies. In our laboratory we have CO 2 cw laser and Nd: YAG ns laser with 1064 nm, 532 nm, and 355 nm radiation wavelengths. We have done applications on laser plasma spectroscopy, oxidation of semiconductors, glass processing and cleaning of different surfaces. Beside various applications we also concentrate on the design of laser systems. We have experience in the design of CO 2 cw lasers and a RF excited CO 2 laser is under development. We also work on the development of cw diode pumped solid state lasers. The design of the various cavities for the DPSS diode pumped solid state lasers is under considerations. The range of our applications will increase with our 1 TW femtosecond laser supported by the State Planning Agency which is under construction now. JTuC66