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[en] We have used two-channel optical pyrometry to study the surface color temperature versus time profiles of aluminum and tungsten irradiated with 100 ps, 5 ns, and 60--70 ns duration pulses of Nd-glass laser in the fluence range of 0.5--15 J/cm². We demonstrate that at fluences of several J/cm² the temperatures of both materials can rise above 5000 K. The maximum observed cooling rates are 5x10¹⁰ K/s, two orders of magnitude less than the theoretical estimation. The importance of these results for the laser annealing experiments on metals and alloys is discussed

[en] We present a detailed technical description of a fast multi-channel pyrometer designed for warm-dense-matter (WDM) experiments with intense heavy ion beams at the neutralized-drift-compression-experiment linear accelerator (NDCX-I/II) at Lawrence Berkeley National Laboratory (LBNL). The unique features of the described instrument are its sub-nanosecond temporal resolution (100 ps rise-time) and a broad range, 1,500 K - 12,000 K of measurable brightness temperatures in the visible and near-infrared regions of the spectrum. The working scheme, calibration procedure, experimental data obtained with the pyrometer and future applications are presented.

[en] Experimental studies of the heat release processes in the apokamp discharge were carried out via the plotting of intensity charts. The procedure was verified with measurement techniques similar to those used in the operation of a disappearing filament pyrometer. A criterion was formulated for its applicability for the study of apokamp discharge in air. The intensity charts obtained at different stages of the formation of discharge confirm the need for gas heating near the discharge channel to form streamers.

[en] In this paper we study the properties of laser-induced plasma channels formed by femtosecond laser radiation in nitrogen. The temperature of the plasma channels was measured using a color pyrometer that measures the brightness temperature. (paper)

[en] In contrast to the single shock compression state that can be obtained directly via experimental measurements, the multi-shock compression states, however, have to be calculated with the aid of theoretical models. In order to determine experimentally the multiple shock states, a diagnostic approach with the Doppler pins system (DPS) and the pyrometer was used to probe multiple shocks in dense argon plasmas. Plasma was generated by a shock reverberation technique. The shock was produced using the flyer plate impact accelerated up to ∼6.1 km/s by a two-stage light gas gun and introduced into the plenum argon gas sample, which was pre-compressed from the environmental pressure to about 20 MPa. The time-resolved optical radiation histories were determined using a multi-wavelength channel optical transience radiance pyrometer. Simultaneously, the particle velocity profiles of the LiF window was measured with multi-DPS. The states of multi-shock compression argon plasma were determined from the measured shock velocities combining the particle velocity profiles. We performed the experiments on dense argon plasmas to determine the principal Hugonoit up to 21 GPa, the re-shock pressure up to 73 GPa, and the maximum measure pressure of the fourth shock up to 158 GPa. The results are used to validate the existing self-consistent variational theory model in the partial ionization region and create new theoretical models

[en] A portable automatic disappearing filament optical pyrometer having low power demand incorporating a solid state line scanner as a sensing element is controlled by a microprocessor to perform a balance between the radiation from a target and a lamp filament to provide a digital indication of the temperature of the target including compensation for emissivity of the target

[en] In the last few years, the application of radiation thermometers has strongly expanded and extended for new fields. Their use may be traced from medicine over heat insulation control in structural engineering and a variety of industrial fabrication branches and scientific experimental techniques for temperature monitoring of turbine blades in supersonic airplanes. More than 100 commercial instruments are used in the temperature range from -100⁰C up to 4000⁰C. The types of equipment offered are accordingly diversified. Several comprehensive presentations of radiation thermometry have been published during the last five years under the overall heading 'temperature measurement'. This lecture therefore confines to special questions important for the selection and calibration of radiation thermometers and often not oberved by users. For this selection, the appendix, by way of trial, gives a systematic compilation of the different aspects in the form of a check list, together with some explanations for the users to test. (orig./RW)

[en] Traditional polymer polarizers degrade in harsh environments and at high temperatures, reducing the polarization effect. In contrast, polarizers produced with refractory metals have vastly improved thermal stability and resistance to harsh environments but are expensive to fabricate. Here we demonstrate prototype refractory metal wire grid polarizers produced by co-sputtering molybdenum and aluminum under specific conditions. Removal of the aluminum through selective dissolution enables the nanostructure array to transmit light. The polarization spans 500–1100 nm and the extinction ratio significantly increases to >100. Possessing broadband polarization and sufficient extinction ratios, the new polarizing film has potential applications in coatings for sunglasses, windows, pyrometers, scientific instruments, and LCD panels. (paper)

[en] The results of calculated theoretical and experimental studies aimed at justifying the use of calibrators, allowing to take into account the uncertainties associated with the difficulty of taking into account the radiation coefficients of controlled surfaces in non-contact pyrometric temperature measurements are given in the work. The relevance of the research is related to the requirements for ensuring the accuracy of non-contact temperature measurements at the level of instrumental errors of pyrometers declared by their manufacturers. Currently, pyrometric measurements are used in virtually all industries and this causes the relevance of the presented research results and proposed technical solutions. The functional scheme of the calibrator using replaceable surface samples is proposed, the temperature of which is measured by pyrometers. (paper)