Phase resolved study of the CRSF in MX 0656-072

MXB 0656-072 is an accreting X-ray pulsar with a Be star companion, showing notable emission in H. In October 2003 this system exhibited a large and extended X-ray outburst. RXTE observations during this outburst indicated a pulse period of 160.4 s and a cyclotron resonance scattering feature in the spectrum at 32 keV. This paper presents pulse profile analysis and phase-resolved X-ray spectroscopy of RXTE observations during this outburst.     

Recent progress in studies of DMSP auroral photographs

A new auroral pattern, which indicates major auroral characteristics in all local time sectors, is presented. It has emerged as a result of extensive study of DMSP-8531 and -10533 auroral photographs. The paper presents also a brief summary of recent studies on the role of the north-south component of the interplanetary magnetic field on large-scale auroral dynamics and on the relationship between substorm energy and the size of the oval.     

Optimization of Surveillance Radar with Instrumented Range

The influence of the instrumented range on the selection of the radar parameters for maximal detection range is described. Procedures for optimization of the performance of the radar by an appropriate setting of its parameters, for specified instrumented range, are presented.     

A Direct Solution to GPS-Type Navigation Equations

One solution to the navigation equations involves iteration on the 4 by 4 augmented range-direction-cosine matrix beginning with an assumed position and so assumed direction cosines, of which there are 12 for 4 satellites. An algebraic, direct solution to this same basic equation set has recently been published. Both of these methods are reviewed. We offer a direct solution using modified functions of the range magnitude data from four satellites to yield user's clock bias correction, user's position, and true range vectors if desired. The highest order of matrix inversion used is 2 by 2. The highest order, nonlinear equation is a numeric square root. The principle of the formulation is use of differences among the range magnitudes and range magnitudes squared. An additional auxiliary difference equation is formed. A computation basis uses the ephimeride differences and an orthogonal vector. The method offers convenience, speed, simplicity, low dimensionality, and precision, with no operational constraints.     

Acceleration of particles by shocks in a cosmic plasma

The theory and observational evidence pertaining to particle acceleration by shock waves in astrophysical objects and in space are systematized. Recent works showing observational and theoretical aspects of the problem dealing with shocks in turbulent media are emphasized. The acceleration of particles by shocks in turbulent media is observed in interplanetary space. This acceleration mechanism is of particular interest from the point of view of the origin of cosmic rays, providing the degree form of the spectrum. The index of the spectrum is close to the observable one for galactic cosmic rays. It depends slightly on specific conditions in the acceleration region. Electron and nucleus acceleration in supernova remnants and in radiogalaxies is discussed, and theory and observational data are compared. The theory of particle acceleration by supersonic turbulence is outlined.     

RF band high resolution sounding of building structures and works

A subsurface radar using a multi-frequency signal has been developed. It is designated for surveying building structures and works. The characteristic feature of this device is the possibility of obtaining sounding plane radio images featuring a high resolution attaining 1…2 cm. The main applications of this device includes the survey of building structures to reveal their heterogeneities and defects and the investigation of premises to detect bugging devices     

Calibration of the Mars Science Laboratory Alpha Particle X-ray Spectrometer

The alpha-particle X-ray spectrometer (APXS) for the Mars Science Laboratory (MSL) mission was calibrated for routine analysis of: Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Zn, Br, Rb, Sr, and Y. The following elements were also calibrated, but may be too low to be measured (10s–100s ppm) for their usual abundance on Mars: V, Cu, Ga, As, Se and W. An extensive suite of geological reference materials, supplemented by pure chemical elements and compounds was used. Special attention was paid to include phyllosilicates, sulfates and a broad selection of basalts as these are predicted minerals and rocks at the Gale Crater landing site. The calibration approach is from first principles, using fundamental physics parameters and an assumed homogeneous sample matrix to calculate expected elemental signals for a given instrument setup and sample composition. Resulting concentrations for most elements accord with expected values. Deviations in elements of lower atomic number (Na, Mg, Al) indicate significant influences of mineral phases, especially in basalts, ultramafic rocks and trachytes. The systematics of these deviations help us to derive empirical, iterative corrections for different rock groups, based on a preliminary APXS analysis which assumes a homogeneous sample. These corrections have the potential to significantly improve the accuracy of APXS analyses, especially when other MSL instrument results, such as the X-ray diffraction data from CheMin, are included in the overall analysis process.