Measurement performance assessment for the ITER CXRS Edge diagnostic system.

Measurement performance assessment has been carried out for the latest design of the ITER Charge Exchange Recombination Spectroscopy (CXRS) Edge diagnostic system. Several plasma scenarios, covering all expected baseline operation regimes for ITER, were used. Various impurity (He, Be, C, and Ne) concentrations for the system whole spatial range (0.5 < r/a < 1.0) were considered. Statistical errors for the measurements of low-Z impurity temperature, density, and rotation velocity were calculated. Other non-statistical error sources were reviewed, including the presence of wall reflections, effects on the active charge-exchange line shape, calibration, and positioning uncertainties. Minimal impurity concentrations, allowing measurements with required accuracy, were obtained. It was shown that the CXRS Edge system will be able to measure primary plasma parameters with required accuracy, space, and time resolution.

Spatially resolved spectroscopic ion temperature measurements at plasma edge of the T-10 tokamak.

Spectroscopic diagnostics of the edge ion temperature were developed on the T-10 tokamak. Spatially resolved measurements of C5+ and other ionization states of carbon spectral line shapes are provided. Spectra were measured with high spectral resolution using 14 lines of sight in one poloidal section of the tokamak. Each measured line-integrated spectrum contains a combination of multiple local spectra with corresponding values of ion temperature. Modeling of spatial distribution of line emissivity and spectral line shapes along the lines of sight allows the reconstruction of the ion temperature profile on the basis of the closest match of measured and modeled spectra. The fine structure of spectral line, Zeeman effect, and apparatus function are taken into account during data processing. Obtained ion temperature profiles, Ti(r), at the plasma edge are in good agreement with ion temperature profiles measured by Charge eXchange Recombination Spectroscopy (CXRS) diagnostics of T-10. Use of the CXRS equipment for measurements of passive spectra can provide additional information on the temporal evolution of the edge ion temperature. Developed diagnostics provide necessary data for the research of geodesic acoustic modes, which are strongly dependent on plasma edge ion temperature.

Charge exchange recombination spectroscopy on the T-10 tokamak.

The charge exchange recombination spectroscopy (CXRS) diagnostics on the T-10 tokamak is described. The system is based on a diagnostic neutral beam and includes three high etendue spectrometers designed for the ITER edge CXRS system. A combined two-channel spectrometer is developed for simultaneous measurements of two beam-induced spectral lines using the same lines of sight. A basic element of the combined spectrometer is a transmitting holographic grating designed for the narrow spectral region 5291 ± 100 Å. The whole CXRS system provides simultaneous measurements of two CXRS impurity spectra and Hα beam line. Ion temperature measurements are routinely provided using the C(6+) CXRS spectral line 5291 Å. Simultaneous measurements of carbon densities and one more impurity (oxygen, helium, lithium etc.) are carried out. Two light collecting systems with 9 lines of sight in each system are used in the diagnostics. Spatial resolution is up to 2.5 cm and temporal resolution of 1 ms is defined by the diagnostic neutral beam diameter and pulse duration, respectively. Experimental results are shown to demonstrate a wide range of the CXRS diagnostic capabilities on T-10 for investigation of impurity transport processes in tokamak plasma. Developed diagnostics provides necessary experimental data for studying of plasma electric fields, heat and particle transport processes, and for investigation of geodesic acoustic modes.

Advanced Thomson scattering system for high-flux linear plasma generator.

An advanced Thomson scattering system has been built for a linear plasma generator for plasma surface interaction studies. The Thomson scattering system is based on a Nd:YAG laser operating at the second harmonic and a detection branch featuring a high etendue (f/3) transmission grating spectrometer equipped with an intensified charged coupled device camera. The system is able to measure electron density (n(e)) and temperature (T(e)) profiles close to the output of the plasma source and, at a distance of 1.25 m, just in front of a target. The detection system enables to measure 50 spatial channels of about 2 mm each, along a laser chord of 95 mm. By summing a total of 30 laser pulses (0.6 J, 10 Hz), an observational error of 3% in n(e) and 6% in T(e) (at n(e) = 9.4 × 10(18) m(-3)) can be obtained. Single pulse Thomson scattering measurements can be performed with the same accuracy for n(e) > 2.8 × 10(20) m(-3). The minimum measurable density and temperature are n(e) < 1 × 10(17) m(-3) and T(e) < 0.07 eV, respectively. In addition, using the Rayleigh peak, superimposed on the Thomson scattered spectrum, the neutral density (n(0)) of the plasma can be measured with an accuracy of 25% (at n(0) = 1 × 10(20) m(-3)). In this report, the performance of the Thomson scattering system will be shown along with unprecedented accurate Thomson-Rayleigh scattering measurements on a low-temperature argon plasma expansion into a low-pressure background.

Investigating the possibility of a monitoring fast ion diagnostic for ITER.

In burning plasma fusion devices, fast ion transport plays a central role in the performances of the machines. Moreover the losses of energetic particles might cause severe damages on plasma facing components. Therefore real time measurements of fast ion transport would provide valuable information for safe and reliable plasma operations. In this paper, we examine the feasibility of a monitoring system based on active charge exchange recombination spectroscopy making use of the 0.5 MeV/amu ITER heating neutral beams for detecting fast (4)He(+2) (alphas) particles in ITER plasmas. There are two time scales relevant to fast ion dynamics: the first is the slowing down time of the distribution function which is of the order of 1 s, and the second is the time scale of burstlike transport events such as collective Alfven mode excitations, which--for typical ITER plasma parameters--can be as low as 0.2-1 ms. To detect such fast events a broadband high-throughput spectrometer is needed, while for the reconstruction of the alpha velocity distribution function a higher resolution spectrometer and longer integration time are necessary. To monitor a spatial redistribution of fast particles due to the propagation of the instability, it is proposed to use a limited number of spatial channels, looking at the charge exchange He II spectra induced by the heating beams, whose energy matches the slowing down energies of fast particles. The proposal is to share the motional stark effect periscope on equatorial port 3 [A. Malaquias et al., Rev. Sci. Instrum. 75, 3393 (2004)] adding additional fibers and suitable instruments. A signal to noise ratio of 5 could be achieved with a spatial resolution of a/15 and a time resolution of 5 ms, in a broad spectral band of 100 A, corresponding to the spectral broadening of the line emitted by alpha particles with energies DeltaE < or = 1.5 MeV. Fast H and D ion populations created by heating neutral beam or ion cyclotron resonance heating are expected to produce significantly lower charge exchange signal levels and can only be monitored on substantially longer time scales as it is expected because of the strong energy difference with respect to the heating neutral beam and the consequently low charge exchange cross sections.

[Relationship of disorders of transcapillary fluid exchange in the lungs and respiratory mechanics in postoperative pulmonary complications]. / Vzaimosviaz' narushenii transkapiliarnogo obmena zhidkosti v legkikh i mekhaniki dykhaniia s posleoperatsionnymi legochnymi oslozhneniiami.

The central hemodynamics, external respiration function, and transcapillary liquid exchange in the lungs were assessed in 23 patients operated on the lungs and in 18 subjected to open heart surgery. The content of extravascular liquid in the lungs was increased during the first hours postoperation in the patients with a complicated course of the postoperative period, in contrast to those with an uneventful course thereof. Disorders of transcapillary liquid exchange did not depend on the status of the central hemodynamics and probably reflected the increased permeability of the alveolocapillary membrane.

[Significance of the energetic value of respiration in the assessment of the degree of strain of compensatory mechanisms in respiratory insufficiency]. / Znachenie énergeticheskoi stoimosti dykhaniia pri otsenke stepeni napriazheniia kompensatornykh mekhanizmov pri dykhatel'noi nedostatochnosti.

A total of 170 examinations of the external respiration function were carried out in 114 patients with postoperative respiratory insufficiency (RI). The patients were examined during air respiration (FiO2 0.21). Pulmonary function was computer monitored. Thirty-four parameters were analyzed, which characterize pulmonary ventilation, gas exchange, respiratory mechanics, and metabolism. Three groups of patients were distinguished: with moderate, expressed, and maximal stages of energy compensation of RI. Augmentation of RI in the course of the postoperative period was found to be characterized by reduction of lung compliance and increase of aerodynamic resistance of the airways and specific and minute Decompensation of RI develops due to fatigue of the respiratory muscles under conditions of increased energy value of respiration, which is proved by the appearance of a reliable inverse correlation between the minute respiratory volume and increased inhalation and exhalation resistance and between respiratory volume and increased inhalation resistance and of a direct correlation between respiratory volume and lung compliance in patients during the maximal energy compensation of respiratory insufficiency. Hence, the energy value of respiration objectively reflects the strain of the compensatory mechanisms during respiratory insufficiency.

[Dynamics of the content of the pulmonary extravascular fluid during extracorporeal detoxication in critical state patients]. / Dinamika pokazatelia ob"ema vnesosudistoi zhidkosti legkikh pri provedenii ékstrakorporal'noi detoksikatsii u bol'nykh v kriticheskikh sostoianiiakh.

Time course of the content of interstitial, cellular, and total fluid in the lungs, of plasma osmolality and sodium concentration was studied in 20 patients with acute renal failure after repair surgery on the heart, thoracic and abdominal organs. Water balance of the lungs was studied by dissolution of electroimpedance indicators before and after removal of 2000-2500 ml of ultrafiltrate. Ultrafiltration of the blood in the course of hemodialysis (group 1) did not lead to a reliable reduction of the volume of intravascular fluid, whereas in group 2 a reliable reduction of the volume of interstitial fluid of the lungs by 34% and of the total liquid volume of the lungs by 29% occurred in the course of hemofiltration.

[Relationship between pulmonary circulation and respiratory mechanics in patients artificial pulmonary ventilation]. / Vzaimosviaz' legochnogo krovoobrashcheniia s mekhanikoi dykhaniia u bol'nykh na IBL.

Thirty-four patients in the early postoperative period after surgery on the lungs and mediastinum and 23 patients after cardiopulmonary bypass surgery have been examined. 187 studies of central hemodynamics and pulmonary function during cardiopulmonary bypass have been performed to investigate the correlation between pulmonary hemodynamics and parameters of respiratory mechanics in the early postoperative period after thoracic surgery. The studies have revealed reverse dependence of lung and chest compliance (C) on pulmonary artery diastolic pressure (PAPdiast) (r = -0.61, p < 0.05) in patients after thoracic surgery with clinical signs of cardiopulmonary failure. When analogous studies were performed in patients with intact lungs after aortocoronary bypass, C/PAPdiast correlation was more close (r = 0.880, p < 0.05). At the same time there is a correlation between C and extracellular fluid volume (r = -0.7). The above correlations to a great extent predetermine the pathogenesis of respiratory failure in the postoperative period.

[Clinical aspects of the use of nubain, tramal and moradol in patients in the early postoperative period]. / Klinicheskie aspekty primeneniia nubaina, tramala, moradola u bol'nykh v rannem posleoperatsionnom periode.

Opioid analgesics were used in 282 patients on the first-third day after heart, lung and abdominal surgery. The main indication for their use was pain syndrome. Adequate analgesia with tramal, nubain and moradol was noted in 73, 76 and 81% of cases. In marked pain syndrome after thoracotomy the most effective agents were moradol and morphine. Computer monitoring of the respiratory function in tramal analgesia has shown a decrease in lung ventilation, esophageal pressure, inhalation volume, O2 production. Tramal, nubain and moradol in analgesic doses did not inhibit respiration. In adequate analgesia there was a decrease in lung ventilation which was not accompanied by shifts in acid-base balance of the arterial blood. The above analgesics had no considerable effect on systemic hemodynamics, though the use of tramal decreased systemic blood pressure and the use of moradol decreased systemic blood pressure and total peripheral vascular resistance. Tramal was most effective for synchronization of spontaneous respiration with a lung ventilation device in prolonged ventilation, as well as for the arrest of muscular tremor in the postoperative period. Tramal was effective in 95% of patients in the early post-anesthesia and postoperative period.

[Possibilities of the method of dilution of electro-impedance indicators in the assessment of volume dynamics of extravascular lung fluid in intensive care and resuscitation units]. / Vozmozhnosti metoda razvedeniia élektroimpedansnykh indikatorov dlia otsenki dinamiki ob"ema vnesosudistoi zhidkosti legkikh v praktike otdeleniia intensivnoi terapii i reanimatsii.

The possibility of using impedance plethysmography to assess changes in the volume of the extravascular lung fluid in intensive therapy and resuscitation patients is discussed. Changes in the volume of the fluid during extracorporeal detoxication are analysed. A correlation was found between these changes and lung distensibility (r = -0.7). A significant diminution of the fluid volume was observed in response to therapeutic doses of Lasix and Nitroglycerin. Data are cited on the increasing (85 percent) volumes of the fluid in preclinical pulmonary edema in patients with left ventricular insufficiency.