[en] We present a 154 pointing IRAM NOEMA mosaic of the CO(1–0) line emission in and around the nearby starburst galaxy M82. The observations, complemented by zero-spacing observations, reach a spatial resolution of ∼30 pc (∼1.″9) at 5.0 km s⁻¹ spectral resolution, sufficient to resolve the molecular gas in the central starburst disk, the outflow, and the tidal streamers. The resulting moment and peak brightness maps show a striking amount of structure. Using a clump decomposition algorithm, we analyze the physical properties (e.g., radii R, line widths σ, and masses M) of ∼2000 molecular clouds. To first order, the clouds’ properties are very similar, irrespective of their environment. This also holds for the size–line width relations of the clouds. The distribution of clouds in the σ ²/R versus column density Σ space suggests that external pressure does not play a significant role in setting their physical parameters in the outflow and streamers. We find that the clouds in the streamers stay approximately constant in size (R ∼ 50 pc) and mass (M ∼ 10⁵ M _⊙) and do not vary with their projected distance from M82's center. The clouds in the outflow, on the other hand, appear to decrease in size and mass with distance toward the southern outflow. The reduction in the molecular gas luminosity could be indicative of cloud evaporation of embedded clouds in the hot outflow.

[en] The characteristic feature of the S^- centres is the p-hole, which corresponds to the lack of one electron to the Ar configuration. Because of this simple structure these centres can be regarded as model systems for the study of defect electrons and for their theoretical treatment. The validity of calculations from first principles made for one-electron systems can be tested for defect-electron systems too. The distribution of the unpaired electron over several shells of neighbour ions was determined by ENDOR measurements in KCl. Experimental data are presented and compared with theoretical calculations

[en] The aircraft’s center of gravity (CG) has a significant influence on the safety and efficiency, which are determined to a large degree by keeping the CG position within the forward and aft limits. Improper loading reduces the aerodynamics efficiency of an aircraft, resulting in higher flight drag. This paper focuses on the theoretical analysis of the influence of variable CG parameter on the fuel consumption. A new model is developed to predict the fuel consumption rate for an aircraft with it’s CG at different position. The numerical result indicates that a more aft CG position produces less drag and, in turn, requires less fuel consumption. (paper)

[en] Over the past several decades, push-broom imaging spectrometers have become a common Earth observation tool. Instruments of this type must be calibrated to convert the raw sensor data into units of spectral radiance. Calibration is in this case a two-step process: First, a sensor model is obtained by performing calibration measurements, which is then used to convert raw signals to spectral radiance data. Further processing steps can be performed to correct for optical image distortions. In this work, we show the complete calibration process for push-broom imaging spectrometers, including uncertainty propagation. Although the focus is specifically on calibrating a HySpex VNIR-1600 airborne-imaging spectrometer, all methods can be adapted for other instruments. We discuss the theory of push-broom imaging spectrometers by introducing a generic sensor model, which includes the main parameters and effects of such instruments. Calibrating detector-related effects, such as dark signal, the noise as a function of the signal, and temperature effects is shown. Correcting temperature effects significantly reduces measurement errors. To determine the signal non-linearity, we built a setup based on the light-addition method and improved this method to allow smaller signal level distances of the sampling points of the non-linearity curve. In addition, we investigate the non-linearity of the integration time. The signal ($\le <!--\; ???\; -->$ 15 %) and the integration time ($\le <!--\; ???\; -->$ 0.5 %) non-linearities can be corrected with negligible errors. After correcting both non-linearity effects, a smearing effect is revealed, which is investigated in detail. We use a collimator and monochromator setup for calibrating the geometric and spectral parameters, respectively. To accurately model the angular and spectral response functions, we propose using cubic splines, which leads to significant improvements compared to previously used Gaussian functions. We present a new method that allows interpolation of the cubic spline based response functions for pixels not measured. The results show that the spectral and geometric properties are non-uniform and change rapidly within a few pixels. The absolute radiometric calibration is performed with a lamp-plaque setup and an integrating sphere is used for flat-fielding. To mitigate the influence of sphere non-uniformities, we rotate the instrument along the across-track angle to measure the same spot of the sphere with each pixel. We investigate potential systematic errors and use Monte Carlo simulations to determine the uncertainties of the radiometric calibration. In addition, we measure the polarization sensitivity with a wire-grid polarizer. Finally, we propose a novel image transformation method that allows manipulation of geometric and spectral properties of each pixel individually. Image distortions can be corrected by changing a pixel's center angles, center wavelength, and response function shape. This is done by using a transformation matrix that maps each pixel of a target sensor B to the pixels of a source sensor A. This matrix is derived from two cross-correlation matrices: Sensor A and itself, and sensor B and sensor A. We provide the mathematical background and discuss the propagation of uncertainty. A case study shows that the method can significantly improve data quality.

[en] The objective of this project was the study of the effects of gravity and curvature on the velocity profiles and pressure gradient for three different fluids flowing through a bend. The bend was of 90 having square cross-section (1 cm/sup */ 1cm). The flow at inlet was assumed uniform. The three fluids under analysis were Sodium, Lithium and Water. For this purpose Navier Stoke's equations that model the flow were discretized using power law scheme. A computer code SIMPMHD as transformed to solve the problem. Flow was considered laminar and results that is velocity and pressure gradient profiles obtained were compared with the theoretical. The results obtained differ from the theoretical results due to turbulence, which was not considered in the present study. The pressure drop calculated through the bend was compared with the pressure drop through same length of horizontal pipe. For laminar case the results were found satisfactory. (author)

[en] Calculations of a stable configuration and the electron structure of A-center in Si passivated by one or two hydrogen atoms are carried out using the semi-empirical method of modified disregard by two-atomic overlap and the non-empirical method of χ_λ-discrete variations. It is found that, differing from vacancy complexes, H implantation to A-center doesn't lead to defect state removal from a forbidden zone

[en] We present the metallicity distribution of red giant branch (RGB) stars in M31's stellar halo, derived from photometric metallicity estimates for over 1500 spectroscopically confirmed RGB halo stars. The stellar sample comes from 38 halo fields observed with the Keck/DEIMOS spectrograph, ranging from 9 to 175 kpc in projected distance from M31's center, and includes 52 confirmed M31 halo stars beyond 100 kpc. While a wide range of metallicities is seen throughout the halo, the metal-rich peak of the metallicity distribution function becomes significantly less prominent with increasing radius. The metallicity profile of M31's stellar halo shows a continuous gradient from 9 to ∼100 kpc, with a magnitude of ∼ – 0.01 dex kpc^–1. The stellar velocity distributions in each field are used to identify stars that are likely associated with tidal debris features. The removal of tidal debris features does not significantly alter the metallicity gradient in M31's halo: a gradient is maintained in fields spanning 10-90 kpc. We analyze the halo metallicity profile, as well as the relative metallicities of stars associated with tidal debris features and the underlying halo population, in the context of current simulations of stellar halo formation. We argue that the large-scale gradient in M31's halo implies M31 accreted at least one relatively massive progenitor in the past, while the field to field variation seen in the metallicity profile indicates that multiple smaller progenitors are likely to have contributed substantially to M31's outer halo.

[en] Possible reasons of the photocurrent decrease under illumination are discussed by comparison of all experimental data obtained in the previous studies of the photosensitivity degradation in CdS:Cu single crystals. By further studies a photosensitivity decrease is found to be due to vanishing of the shallow donors which compensate the r-centres. A degradation mechanism consisting in transformation of the shallow donors into rapid recombination s-centres, due to their association, is suggested. On heating in darkness these s-centres dissociate to recover both, the initial density of the shallow donors and the high photosensitivity. (author)

No abstract available

[en] A new approach for quantitative analysis of self-potential (SP) data is introduced. In this paper, anomaly of SP is associated with simple geometric models such as a vertical cylinder, a horizontal cylinder and a sphere object. Then, in order to estimate the depth, the electric dipole moment, the anomaly body’s centre, the geometrical form factor and polarization of the anomaly, the method was developed and implemented. The development and implementation of the method is based on the global optimization concept. This method uses Quantum-behaved Particle Swarm Optimization (QPSO) algorithm to overcome the inversion problem on SP anomaly modelling. The QPSO algorithm was randomly tested on synthetic data which consist of different random noise levels. The result shows a close agreement between the assumed and the measured parameters. At last, the validity of the method was tested on real SP anomaly data and compared to the results given by other advanced inversion approaches. (paper)