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This work reports an extensive collection of 120 atomic transition probabilities of Kr II lines in the spectral region 350–720 nm, all of them measured in an emission experiment. For many of them, these are the first data up to the authors' knowledge. Relative intensity measurements have been obtained on a pulsed discharge lamp and the absolute Aki-values have been calculated by considering the available data from the literature as reference for the plasma temperature diagnosis. Excitation temperature (14 000–28 000 K) has been determined by using the Boltzmann-plot method. The plasma electron density (0.2–0.8 × 1023 m−3) has been determined by two-wavelength interferometry. This work extends a previous one already published by our laboratory [1, 2]. Comparisons have also been made with previous literature values.

This work reports information on the pressure broadened profiles of the HeII P α , P β and P$_\gamma$ spectral lines measured in a pulsed discharge lamp. Information relative to the line shapes, full width at 1/2, 1/4 and 1/8 of the maximum intensity and the dip of the HeII 320.3 nm is provided. The electron density has been determined by two-wavelength interferometry and from the Stark width of the HeI 501.6 nm. and ranges during the HeII emission from 0.54 to $0.64 \times 10^{23}$ m -3 in the plasma. Temperature (1.7–2.4 eV) has been simultaneously determined from the Boltzmann-plot of HeI and from local thermodynamic equilibrium (LTE) assumptions. The final results have been compared with most of the previous existing data.

A set of experimental Stark width and shift parameters of visible singly ionized silicon spectral lines is reported in this paper. Measurements have been made on a pulsed plasma generated in a linear discharge lamp filled with a mixture of silane and helium. Electron density and temperature in this plasma range from 0.2 to 0.9 × 1023 m−3 and from 16 000 to 20 000 K respectively. Electron density has been simultaneously determined by two-wavelength interferometry and from Stark broadening of He I 501.6 nm, He I 728.1 nm and Hα lines. Temperature has been simultaneously determined from a Boltzmann plot of He I lines, from absolute emission of He I lines and from a Boltzmann plot of Si II lines. Dependences of measured Stark parameters on electron density and temperature have been investigated and the final results have been compared with most of the previous experimental data as well as with some theoretical models.

This work reports atomic transition probabilities of 33 spectral lines belonging to 3s-3p, 3p-3d and 3d-4f multiplets of O II, all of them measured in the 405-465 nm spectral region in an emission experiment. Relative intensity measurements have been made on a pulsed discharge lamp and the absolute Aki-values have been obtained taking the NIST database as a reference in temperature diagnosis. The results of this work confirm the other recent available data measured by Veres and Wiese (Veres G and Wiese W L 1996 Phys. Rev. A 54 1999) with a different source and the calculations of Bell et al (Bell K L, Hibbert A, Stafford R P and McLaughlin B M 1994 Phys. Scr. 50 343) with a very satisfactory agreement (usually within 10%).

This work reports a collection of 35 transition probabilities of lines in the spectral region 450{580 nm, all of them measured in an emission experiment. Relative intensity measurements have been made in a pulsed discharge lamp and the absolute Aki values have been obtained by using reference data taken from the literature. The electron density has been determined by two-wavelength interferometry and ranges from 0: 1t o 0:810 23 m 3 in the plasma. Temperature (14 000{24 000 K) has been simultaneously determined from three dierent methods, including the Boltzmann-plot of KrII lines and the KrII/KrI intensities ratios. The nal results have been compared with most of the previous existing data.

This work reports information about Stark broadening and shift parameters of a very extensive collection of visible singly ionized nitrogen lines. All of them were measured in a linear discharge lamp from a mixture of nitrogen and helium. Electron density and temperature range in this experiment from 0.2 to 1.1 × 1023 m-3 and from 17 000 to 29 000 K, respectively. The first one has been simultaneously determined from two-wavelength interferometry and from the Stark broadening of He I 471.3 nm, the second from a Boltzmann plot of N II lines and from N II/N I intensity ratios. Dependences of these Stark parameters with temperature and electron density have been investigated and the final results have been compared with most of the previous experimental data as well as with two theoretical models. All relevant details relative to this experiment are given in the paper.

A very extensive compilation of Stark widths and shifts for more than 125 Ar II visible spectral lines is presented in this work. These atomic parameters have been measured in a pulsed discharge lamp by using different mixtures of pure argon or argon and helium. The electron density, which typically ranges from 0.2 to has been determined interferometrically and, in the case of pure argon plasmas, also spectroscopically from -Stark broadening. The Ar II excitation temperature (15 000-31 000 K) has been determined by Boltzmann-plot techniques from the intensity of Ar II lines. A detailed description of all the relevant points in this kind of measurement is given. Comparisons with most of the data published about this topic for Ar II are also included.

Stark widths and shifts of 35 singly charged krypton ion spectral lines have been measured in a pulsed discharge lamp, where electron density ranges from $0.35--0.8\ifmmode\times\else\texttimes\fi{}{10}^{23}\phantom{\rule{0.3em}{0ex}}{\mathrm{m}}^{\ensuremath{-}3}$ and electron temperature ranges from $15000--27000\phantom{\rule{0.3em}{0ex}}\mathrm{K}$. This work extends a previous one [A. de Castro et al., J. Phys. B: At. Mol. Opt. Phys. 34, 3275 (2001)] already published by our laboratory. Intramultiplet and intratransition nonregularities have been found and have been explained by considering the perturbing levels effect on the Stark parameters for each one of the measured spectral lines.

We developed a model of corneal haze following photorefractive keratectomy (PRK) in Iber Braun hens and studied optical properties. The animals underwent PRK for -9.0 diopters of myopia and were divided into groups based on treatment with different wound-healing modulators. At different time points postoperatively, we evaluated haze by slit-lamp microscopy. An experimental device was developed to measure transmittance spatial maps and forward scattering of He-Ne laser light in the excised corneas. Subjective and objective haze measures were compared for each group at the different times. Keratocyte densities were determined by optical microscopy and keratocyte sizes by electron microscopy. The agreement between experimental results and a simple numerical model of scattering suggests that increases in stromal keratocyte density after PRK might explain the degree of corneal haze.

Stark widths and shifts of 25 visible singly ionized krypton lines are presented in this paper. All of them were measured in a pulsed discharge lamp from a mixture of krypton and helium. The electron density, which typically ranges from 0.2 to 1.8×1023 m-3 has been simultaneously determined from two-wavelength interferometry and from the Stark broadening of the He I 388.865 nm. The excitation temperature, from 16 000 to 24 500 K, has been measured from the Boltzmann plot of Kr II lines, which has allowed us to recalculate some Kr II transition probabilities. Comparisons with most of the data published to date about this topic in Kr II are also included.

A design procedure is described to obtain monochromators for specific applications, which are made from optical devices that can be easily acquired or built. This procedure makes use of a constant angular deviation system consisting of a transmission grating, operating in a symmetrical arrangement, and a flat mirror which makes a fixed angle with it. An analysis of the characteristic parameters of the design and of the constraints which have an effect on them, is presented as well as two examples of applications of the procedure.