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The A2Πi state of 12C16O+ has been reinvestigated using high-resolution, emission spectra obtained via Fourier-transform spectroscopy of the (0, 1), (0, 2), (1, 0) and (1, 1) bands of the Comet–Tail (A2Πi − X2Σ+) system with accuracy of up to 0.005 cm−1. The high temperature (900 K) of the emission discharge inside the hollow-cathode lamp permitted monitoring of high rotational quantum levels in A2Πi(v = 0, 1) up to J = 48.5. All these bands together with the X2Σ+ − X2Σ+(10, 1) and (10, 2) transitions deriving from a complex, spin-orbit, spin-electronic and L-uncoupling A2Π(v = 0) ∼ X2Σ+(v = 10) interaction as well as the B2Σ+ − X2Σ+(6, 10) frequency transitions from our previous study were taken into consideration. In total, 1849 spectral lines were included in the comprehensive deperturbation analysis. This fit leads to a much improved description in terms of deperturbed molecular constants and interaction parameters compared to the previous studies of the same energy region in CO+. Moreover, the ro-vibronic term values of the A2Πi(v = 0) level and its perturber X2Σ+(v = 10) were determined as well as Λ-doubling of A2Πi(v = 0,1), γ-doubling of X2Σ+(v = 10) and percentage 2Π character of these levels were considered in detail.

In the emission spectrum of the CO molecule thirteen bands of the fourth-positive ( A 1 Π → X 1 Σ + ) band system were photographed and analysed. Under high resolution and by using conventional photographic spectroscopy, the following excited bands: 7–16, 7–17, 8–18, 8–19, 9–19, 9–20, 10–20, 10–21, 11–21, 11–22, 12–22, 13–24, 14–26 and approximately 1340 molecular lines were recorded. A rotational analysis of the bands: 7–17, 8–18, 8–19, 9–20, and 11–22 were carried out for the first time, and the bands 11–21 and 14–26 were identified and analysed for the first time. After detailed rotational analysis of the bands, experimental rovibronic term values of the A 1 Π ( v = 9 –14) levels were determined for the first time. Individual and equilibrium molecular constants of the A 1 Π state as well as the Franck–Condon factors were determined for the analysed bands. Moreover, a region of analysed perturbations of the A 1 Π ( v = 7 –14) levels was extended to the J ⩾ 30 rotational levels. Also, most of theoretically predicted perturbations of the v A = 13 and 14 levels were identified for the first time.

In the isotopic 14C16O molecule eight bands of the fourth-positive (A1Π → X1Σ+) system were investigated for the first time. Under high resolution, using conventional photographic emission spectroscopy technique, highly excited 7–19, 8–20, 9–21, 10–21, 11–22, 12–23, 12–24 and 13–24 bands were recorded and spectroscopically analyzed. First individual constants of the rovibronic structure: B v ′ and D v ′ of both A1Π and X1Σ+ states as well as the equilibrium constants: Be, αe, γe, ωe, ωexe, and ωeye of the upper A1Π state were obtained. First values of band origins for all studied bands were also computed. On the basis of these parameters and the ground X1Σ+ state constants recalculated isotopically from Le Floch [1] spectroscopic constants, the first experimental rovibronic term values of the A1Π state vA = 7–13 levels were calculated. Numerous observed rotational perturbations of the A1Π state were identified and compared with the theoretically determined ones.

This paper presents the computational fluid dynamics (CFD) analysis of the flow inside a cyclone with the division of gas and particle flow in a vortex finder. A doubled vortex finder which was used for the investigations divides gas cleaned in the cyclone into two parts. The gas elements exiting the cyclone through the external tube (i.e. bleed flow) were 20%, 40% and 57%, respectively. The particle size distribution of both streams has also been determined. The Reynolds-averaged Navier–Stokes equations with the Reynolds stress turbulence model (RSM) were used for the analysis. The Lagrangian method was employed to track the particle motion and calculate the cyclone and the efficiencies of division. The conducted division of exhaust gas practically does not change the gas flow and the efficiency of the cyclone. However, the particle size distribution of both gas streams is different. The difference in the particle size can be used for subsequent cleaning of bleed flow in a bag filter and for improving the efficiency of the modified system of the cyclone with an additional filter. Such a system would remove more dust than dividing the gas stream alone.

The 1–0, 6–0 and 6–1 bands of the A 2 Π i → X 2 Σ + system of 13C16O+ and the 2–0 and 2–1 bands of the A 2 Π i → X 2 Σ + system of 14C16O+ have been recorded at high resolution for the first time. The 0–2 and 5–0 bands of the A → X system of 12C16O+ have also been recorded at higher resolution than in previous work. The spectra were excited in an air-cooled hollow cathode discharge and photographed using a 2-m plane grating spectrograph. The spectral resolution and the Doppler-broadened line widths are both ∼0.12 cm−1, and the experimental measurement precision of resolved lines is ∼0.02 cm−1. The measured line positions, sometimes in combination with literature data on the B 2 Σ + → A 2 Π i transition, have been employed in deperturbation analyses of level crossings in the near-degenerate A(0)∼X(10) and A(5)∼X(14) interactions in 12C16O+, the A(1)∼X(11) and A(6)∼X(15) interactions in 13C16O+, and the A(2)∼X(12) interaction in 14C16O+. No radial dependence of the electronic perturbation matrix elements HSO(r) and HRE(r) could be detected over the narrow range of r-centroids (1.477–1.501 A), and the mean values of these parameters are HSO = −49.06(15) cm−1 and HRE = 0.211(2). Using iteratively improved RKR potentials and FC-overlap integrals, the mean HSO and HRE were employed in least-squares analyses of A → X literature data involving A(υ) levels of the three isotopologues that are affected by interactions with one or two distant X(υ∗) levels. The fitted parameters of the A 2 Π i state (Bυ, Aυ, ADυ, pυ, qυ) exhibit υ-dependences that are much smoother than those employing perturbed parameters determined in previous investigations. In addition, a significant electronic isotope effect has been characterized. The separations Te(A)–Te(X) of the minima of the A and X states of 13C16O+ and 14C16O+ are less than that of 12C16O+ by 0.39 and 0.73 cm−1, respectively. Although Born–Oppenheimer breakdown of this magnitude is surprising, it is similar to that found for the B 2 Σ + state of CO+.

We discuss here various methodologies and an optimal strategy of the temperature and emission measure diagnostics based on Hinode X-Ray Telescope data. As an example of our results we present the determination of the temperature distribution of the X-rays emitting plasma using a filters ratio method and three various methods of the calculation of the differential emission measure (DEM). We have found that all these methods give results similar to the two filters ratio method. Additionally, all methods of the DEM calculation gave similar solutions. We can state that the majority of the pairs of the Hinode filters allows one to derive the temperature and emission measure in the isothermal plasma approximation using standard diagnostics based on the two filters ratio method. In cases of strong flares one can also expect good conformity of the results obtained using a Withbroe – Sylwester, genetic algorithm and least-squares methods of the DEM evaluation.

state. Therefore, upper vibrational levels (v 0 ‚ 3) of the A 1 ƒ state cannot be determined by means of the equilibrium constants calculated in the previous works. Due to so far unidentifled A 1 ƒ state perturbations, the reduction of the wave numbers to the rovibronic parameters was carried out by means of individual, band-by-band analysis method, using with this end in view the nonlinear least squares method introduced by Curl and Dane, and Watson. This method allowed one to make already calculated constants of the rovibronic structure of regular lower state X 1 § + of AiX system independent of possible perturbations appearing in the upper state of A 1 ƒ of this system. It also enabled one to calculate for the flrst time the real (perturbed) term values for the A 1 ƒ (v 0 = 0, 1, 2, and 3) state of the 12 CH + ion molecule. These values suggest that rotational irregularities in the A 1 ƒ state examined are negligibly small. In order to conflrm the nonexistence of rotational perturbations in the A 1 ƒ (v 0 = 0, 1, 2, and 3) state, up to the observed Jmax ¶

In the electronic emission spectrum of the 12 C 16 O + molecule, 11 bands of the Comet–Tail ( A 2 Π i – X 2 Σ + ) system have been recorded and analyzed. Spin splitting in most of the observed lines of the 0–2, 1–0, 2–0, 2–1, 3–0, 4–0, 4–2, 6–0, 7–0, 7–1, and 8–1 bands, comprising nearly 3400 lines, has been recorded under high resolution by conventional spectroscopy. The rotational analysis of bands has been performed by nonlinear least-squares procedures and by means of effective Hamiltonians of Brown et al. and the rovibronic structure parameters have been obtained. The data of bands of the A – X system and earlier analyzed bands of the B – X and B – A systems have been merged together. As a result of this global fit, the state of information about the energy structure has been significantly enlarged for the A state and enlarged and improved for the X state. Also RKR potential curves for both states and Franck–Condon factors as well as r -centroids of the Comet–Tail system of CO + have been calculated.

Conventional, high resolution molecular spectroscopy has been employed to record emission spectra of the first negative bands system in the 12C16O+ molecule. Twenty two bands form the 0-v”,1-v”, 2-v”, 3-v”, 4-v”, 5-v” progressions and 6-10 band were photographed in the 34000-46000 cm-1 spectral region. The reduction of the spectrum for the individual bands has been performed via a nonlinear least-squares fit with the effective Hamiltonians of Brown et al. [J. Mol. Spectrosc. 74, 294 (1979)]. The final molecular constants for both the $B^{2}\Sigma^{ + }(v=0 - 6)$ and $X^{2}\Sigma^{ + }(v=0 - 10)$ states were obtained from global merge calculations of the present data of the $B\rightarrow X$ system and previously obtained in our laboratory data for $A \rightarrow X$ and $B \rightarrow A$ systems in the CO + molecule. Merged molecular parameters have been used in order to the determine the equilibrium constants for both considered states. The $\gamma_{e} = 2.194(14) \times 10^{-2}$ cm-1 and $\alpha_{\gamma e} = -1.021(64)\times 10^{-4}$ cm-1 constants for the $B^{2}\Sigma^{ + }$ state were obtained for the first time. The RKR potentials have been calculated for both combining states, as well as Franck-Condon factor and r-centroids for the first negative system in the 12C16O + molecule. Furthermore, we report the value of the electronic isotopic shift $\Delta\nu_{e} = -0.395$ cm -1 of the $B\rightarrow X$ system in 13C16O + , calculated on the basis the presents results and those obtained by us previously for the 13C16O + molecule.

Ten new 0–4, 1–0, 1–1, 3–3, 3–5, 3–6, 3–7, 4–6, 4–7, and 5–8 bands of the first-negative (B2Σ+→X2Σ+) system of 13 C 16 O + were observed and their rotational structure was analyzed for the first time. These bands were recorded by means of classical spectrographical methods under high resolution. This allowed one to observe a spin splitting in most lines of the recorded bands. The effective Hamiltonian of Brown with the matrix elements for the 2 Σ + states taken from a work by Amiot et al. [J. Mol. Spectrosc. 87 (1981) 196–218] has been used to obtain the rovibronic structure parameters of the individual bands from the observed wavenumbers of lines. The molecular constants obtained in this way were then merged with those derived by us earlier. For this purpose the least-squares merge procedure was used. This made it possible to obtain a wide set of precise constants of the rotational structure in 15 vibrational levels, for the X 2 Σ + (v=0–8) ground state and for the second B2Σ+(v=0–5) excited state in 13 C 16 O + . On the basis of these final constants it was possible to calculate the equilibrium molecular constants, and the RKR potential curves for the X2Σ+ and B2Σ+ electronic states as well as Franck–Condon factors and r-centroids for the first-negative bands in 13 C 16 O + .

The emission spectrum of the Angstrom system (B 1 Σ + → A 1 Π) of 1 3 C 1 6 O was recorded and analysed by classical photographical spectroscopy. Under high resolution and with a precision estimated to be 0.010-0.020 cm - 1 the bands 1-2, 1-7, and 0-6 were recorded for the first time and the 0-1, 0-2, 1-1, and 1-5 bands were rephotographed and reexaminated. After the rotational analysis of the bands the following constants were calculated: (1) the rotational constants Β v , D v for the B 1 Σ + and A 1 Π states; (2) the equilibrium constants B e , α e , D e , and β e for the B 1 Σ + state; (3) the v 0 band origins. A combined analysis of the currently observed Angstrom bands and the previously observed Herzberg (C 1 Σ + → A 1 II) and the (E 1 Π → A 1 Π) bands made it possible to perform a precise relative characteristic of the B 1 Σ + (v = 0 and 1), C 1 Σ + (v = 0) and E 1 Π(v = 0) rydberg levels in 1 3 C 1 6 O. Numerous rotational perturbations observed in the A 1 Π state were confronted with the perturbations predicted from the theoretical calculations.

In the emission spectrum of the CO + ion new so-far unobserved 0-2, 1-3, and 2-1 bands and so-far unanalyzed 1-2 and 2-0 bands belonging to the Baldet-Johnson ( B 2 Σ + - A 2 Π i ) system have been identified and recorded by means of conventional spectroscopy. The individual analysis of the recorded bands and the merged analysis of the Baldet-Johnson system which is now extended to eight bands made it possible to considerably improve and extend the information on both the B 2 Σ + and A 2 Π i excited states of the CO + molecule. Especially, the information about equilibrium constants of the rovibronic structure and the potential curve parameters of both states have been improved and extended. Also a new quantitative classification of the relative band intensities of the now enlarged Baldet-Johnson system has been proposed.

The effect of hole doping on the exchange coupling of the nearest neighbor (NN) Mn pairs in Zn$_{1-x}$Mn$_x$Te is probed by inelastic neutron scattering. The difference in the NN exchange energy $\Delta J_1$ in the presence and in the absence of the holes is determined. The obtained value of $\Delta J_1$ is in good agreement with the predictions of the Zener/RKKY model, even on the insulator side of the metal-insulator transition., Comment: 4 pages, 2 figures, submitted to PRL

The first direct determination of the hole-induced ferromagnetic contribution to the nearest-neighbor (NN) Mn–Mn exchange in Zn 1− x Mn x Te is reported. The difference between the NN exchange constants for insulating and strongly p-type samples was found by comparing inelastic magnetic neutron scattering from NN Mn–Mn pairs in the specimens.

In the rare14C16O isotopic molecule the so far unobserved 1–2 band belonging to the Angstrom (B 1Σ+-A 1Π) system has been photographed under high resolution by conventional spectroscopy. After the rotational analysis of the band the rotational constantsB v andD v of both combined levels and thev 0 band origin have been calculated. A combined analysis of the bands belonging to the Angstrom, Herzberg andE 1Π-A 1Π systems made it possible to perform a precise relative spectroscopic characterization of thev=1 level of theB 1Σ+ state and thev=0 levels in theB 1Σ+,C 1Σ+ andE 1Π Rydberg states in the14C16O molecule. Numerous rotational perturbations observed inA 1Π state in this molecule have been identified.

Four bands (with v' = 2–5 and common v'' = 0) of the comet-tail (A2Πi → X2Σ+) band system were recorded under high resolution by conventional, photographic spectroscopy and their modern analysis was carried out. The current investigations include a much greater region of the observed 12C18O+ molecule spectrum than before. In particular, the 5–0 band was recorded and studied for the first time. Thanks to the application of high resolution it was possible to record the complete set of 12 branches in all bands studied. The high precision of the measurements and the use of the commonly accepted theoretical model allowed us to obtain full spectroscopic characteristics of the analysed excited vibrational levels v' = 2–5 of the upper A2Πi state. In particular, the values of AD, p and q molecular constants for v' = 2, 3, 4 and all rotational parameters for v' = 5 were extracted for the first time. Also, the first values of the numerous equilibrium constants, as well as RKR parameters, were calculated. Finally, Franck–Condon factors and r-centroids for the comet-tail bands were provided.

We report stochastic diffraction simulations of magnetic multilayered systems. Results show that spectrum fringes from a system of many magnetic domains is a non-random effect - i.e., such fringes cannnot occur in the total absence of interlayer spin correlations. Simulation of diffraction spectra from superlattices with interlayer coupling probability 0

Neutron diffraction is a powerful tool for investigating interlayer coupling phenomena in magnetic superlattices. In the absence of interlayer spin coherence the diffraction spectrum has the form of a broad smooth maximum, i.e., it essentially reproduces the shape of the single-layer structure factor. In contrast, spectra from correlated superlattices exhibit characteristic fringe patterns. However, doubts are sometimes expressed as to whether the presence of fringes indeed provides meaningful evidence for interlayer coherence; such opinions are usually based on results of computer simulations that produce “fringelike” features even though the magnetization in consecutive layers changes in a random fashion. Clarity in this issue is certainly of importance, especially in studies of systems with antiferromagnetic layers, in which neutron diffraction is practically the only experimental tool capable of detecting interlayer spin coherence. We report the results of thorough computer modeling studies that show that the “pseudofringes” obtained from simulations on uncoupled superlattice models disappear after averaging the data from a sufficiently large number of random configurations. It is a reasonable expectation that in a real superlattice each magnetic layer breaks into a large number of domains, so neutrons passing through the sample “see” different situations. Hence, realistic modeling does require averaging over many random configurations, and our results point out that in following such a procedure, the “fringelike” features eventually wash out, and the simulated spectra become fully consistent with the analytical single-layer structure factor. However, there is still the possibility that in special situations the spectra from uncoupled systems may exhibit fringes. Suppose that the system symmetry allows discrete domain states (e.g., corresponding to in-plane easy axes), and that the average domain size and the superlattice period are both small in comparison to the coherence length of the incident neutron wave (since the coherence length in a typical experiment is of the order of 1000 A, this is not an unusual situation). Then, arguably, there is always a finite probability that equivalent domains located in different layers will fall into the “coherence volume,” and give rise to constructive interference, even though the domains are not coupled by any interactions. In view of that, our work included simulations on several different model systems that might, in principle, exhibit such an effect. Again, the averaged data from many thousands of runs showed no anomalies at the expected fringe positions, providing more evidence that neutron diffraction allows a fully reliable distinction of coupled and uncoupled superlattice systems.Neutron diffraction is a powerful tool for investigating interlayer coupling phenomena in magnetic superlattices. In the absence of interlayer spin coherence the diffraction spectrum has the form of a broad smooth maximum, i.e., it essentially reproduces the shape of the single-layer structure factor. In contrast, spectra from correlated superlattices exhibit characteristic fringe patterns. However, doubts are sometimes expressed as to whether the presence of fringes indeed provides meaningful evidence for interlayer coherence; such opinions are usually based on results of computer simulations that produce “fringelike” features even though the magnetization in consecutive layers changes in a random fashion. Clarity in this issue is certainly of importance, especially in studies of systems with antiferromagnetic layers, in which neutron diffraction is practically the only experimental tool capable of detecting interlayer spin coherence. We report the results of thorough computer modeling studies that show ...

Analyse rotationnelle des bandes O-1 et O-2. La structure de ces bandes montre que l'etat E n'est pas perturbe alors que l'etat A est fortement perturbe. Determination des constantes de rotation

In the emission spectrum of the carbon monoxide isotopic molecules the Herzberg bands at a 0.6 A/mm dispersion have been obtained. For the13C16O molecule all the seven bands of this system have been obtained and for the12C16O molecule the 0–2 and 0–3 bands only. A rotational analysis of these bands has been performed and the following constants were determined: the rotational constants of theC 1 Σ + andA 1II states, the band origins for theC 1 Σ + −A 1 Π transition, and the new vibrational constants for theC 1 Σ + state.

Seven bands ((0–0) – (0–6)) belonging to the Herzberg system of 13C18O have been recorded in emission using conventional photographic spectroscopy. For the first time, lines of this system have been recorded at high resolution and identified. After the rotational analysis of bands, the rotational constants of the C1Σ+ (ν = 0) and A1Π (ν = 0–6) states, as well as the vibrational constants of the A1Π state, have been determined. A combined analysis of the bands of the Herzberg and Ångström systems have made it possible to determine the constants of the B1Σ+ state more precisely. Numerous rotational perturbations observed in the A1Π state in this isotopic molecule have been analyzed.

In the emission spectrum of the12C18O isotopic molecule the 0–0, 0–1 and 0–2 bands of twoE 1 Π-A 1 Π andB 1 Σ + transitions have been photographed at high resolution. After a rotational analysis of bands the following molecular constants have been calculated: (1) the rotational constantsB o andD o for the upperE 1 Π andB 1 Σ + states andB v ,D v for theA 1 Π state, (2) the reduced band originsc ov , for both transitions, (3) the Λ-doubling constants for theE 1 Π state, (4) the distances betweenv=0 levels in theE 1 Π,C 1 Σ + andA 1 Π states. Some molecular constants have been derived from the combinational analysis of bands which belong to theE 1 Π-A 1 Π andB 1 Σ +-A 1 Π and alsoE 1 Π-A 1 Π andC 1 Σ +-A 1 Π transitions. Strong perturbation of theA 1 Π state bye 3 Σ − nearby electronic state, observed in the 0–0 band ofB + Σ +-A 1 Π system has also been analysed.