Observations of A0535+26 transient X-ray source

Observations of the transient X-ray A0535+26 source with the SIGNE-2MP instrument on-board the Soviet “Prognoz-6” and “Prognoz-7” satellites are considered in the paper.     

Prognoz-6 data about ultraviolet sky background in dark and Milky Way regions of the sky

Ultraviolet spectra (1100–1900 Å) of the sky background of 10 wide angle (6°×6°) regions obtained between 70 000 km and 200 000 km from the Earth with the photoelectric spectrometer “GALACTIKA” on board the satellite “PROGNOZ-6” are considered. The spectral energy distribution of the sky background, after subtraction of the stellar component, is similar for regions on both sides of the Milky Way and exhibits a strong U.V. light contribution. On the contrary, the Milky Way (l_II=190° b_II=+6°) is less rich in far U.V. light; this can be related to the predominance of an expected selective absorption near the galactic plane. The nature of U.V. excess at high galactic latitudes needs further investigations.     

The X-ray properties of accreting black holes

Accreting black holes in binary systems exhibit two properties that distinguish them from the vast majority of binary X-ray sources: (1) rapid ≤ 1 s variability and (2) bi-modal spectral behaviour. These findings are based primarily on the observed properties of Cyg X-1 where an estimate of the X-ray source mass from radial velocity studies indicates a mass of 10 M. The recently suggested black hole candidacy of LMC X-3 is based on a similar mass estimate. The X-ray properties are similar to those of Cyg X-1 in its “high state”. The unique spectral properties of these systems are used to search for other similar systems, and new “possible” candidates are suggested, that include several transient sources. A possible spectral connection between these systems and their more massive counterparts in AGN is discussed.     

A theoretical review of SS 433

The “twin jet model” for SS 433 is briefly described, and its likely superiorority to other models demonstrated. It is then used as a framework within which the implications of the main observational results are discussed. Many theoretical questions about SS 433 are raised, but only few are answered.     

Type I supernovae origin: “Dualistic” hypothesis

Stars that explode as Type I Supernovae (SNI) are white dwarfs with masses practically equal to the Chandrasekhar limit M_ch. These white dwarfs forme either as a result of gas overflow onto a degenerate component in a binary system or due to the evolution of nuclei of the stars whose mass, on the main sequence, was 3 to 7 M_o. The masses of their nuclei are quite close to M_ch. It is convenient to consider three types of stellar evolution 1) “hyperbolic”: masses of nuclei formed as a result of evolution are > M_ch; such evolution ends in a Type II Supernova (SNII) outburst; 2) “parabolic” - masses of nuclei ≈ M_ch, with the evolution ending in an SNI outburst; 3) “elliptical” with nuclei masses < M_ch. The latter type of evolution leads to the formation of planetary nebulae and white dwarfs. A new hypothesis is suggested that explains more frequent occurrence of SNI in irregular galaxies by flashes of star formation.     

Updated TUS space fluorescence detector for study of UHECR

The TUS (Tracking Ultra-violet Set up) space fluorescence detector has to be launched in 2010 as a separated platform in Foton (Bion) mission prepared by the Samara enterprise. This detector was designed for another satellite and the updated variant of the TUS detector for a new platform is presented. The data on UV glow of the atmosphere obtained in operation of one pixel of the TUS detector on board the Moscow State University “Universitetsky-Tatiana” satellite was taken into account in design of the updated TUS detector. The data on UV transient flashes registered in “Universitetsky-Tatiana” mission are of special interest. Electronics of the TUS detector able to select and register different types of UV events in the atmosphere is presented.     

IONOSAT – Ionospheric satellite cluster

The IONOSAT project (from IONOspheric SATellites) is proposed by National Space Agency of Ukraine for First European Space Program as a part of Space Weather (SW) Program. As it is commonly accepted, Space Weather means the changes of the conditions on the Sun, in solar wind, magnetosphere and ionosphere which may affect the operation and reliability of on-board and ground technological systems and threaten human health. In this chain ionosphere is specific and integral part of SW formation. Moreover, namely in the ionosphere main part of the energy absorption of Sun-activated sporadic corpuscular and radiation fluxes takes places. The excitation of ionosphere by falling fluxes produces its “luminescence” in wide frequency band – from ULF waves till ultraviolet – and by this ionosphere works as an efficient “screen” or SW indicator.A goal of the proposed project is long-term spatial–temporal monitoring of main field and plasma parameters of ionosphere with aim to further develop fundamental conceptions of solar-terrestrial connections physics, nowcasting and forecast of SW, and diagnostics of natural and technogenic hazards with the help of scientific payload installed on-board a cluster of 3 low-Earth orbit (LEO) microsatellites (tentative launch date – 2012 year).The state of the project proposal and realization plans are discussed.     

Theromonuclear flashes in accreting neutron star envelopes

The thermonuclear model for x-ray burster and “soft transient” is discussed. The mass accretion rate M, the chemical composition of accreted matter, the gravitational potential of the neutron star and thermal state of outer layer / or core/ are the main parameters which determine the burning regime. Importance of nuclear network used for the properties of subsequent flashes is pointed out.     

Problems with the concept of the inflationary universe

The picture of an exponentially increasing, “inflationary” phase of the early universe (Guth 1981; Linde 1982; Albrecht and Steinhardt 1982) may point the way to an understanding of our present universe without reference to extremely specific initial conditions. The model rests, however, on several assumptions which deserve critical examination.     

On possible genesis of fractal dimensions in the turbulent pulsations of cosmic plasma – galactic cosmic rays – turbulent pulsation in planetary atmosphere system

The spectrum of turbulent pulsations induced in the atmosphere by the galactic cosmic rays is defined. A possible manifestation of genesis of fractal dimensions in the system of “spectrum of turbulent pulsations of cosmic plasma – galactic cosmic rays’ spectrum – spectrum of atmospheric turbulent pulsations” is analyzed.     

X-ray synchrotron nebulae and the origin of neutron stars

“With all reserve, we advance the view that a supernova represents the transition of an ordinary star into a neutron star.”This conclusion, reached just 50 years ago in a classic paper by Walter Baade and Fritz Zwicky (1934), was published three decades before the first direct observational evidence for the existence of neutron stars was uncovered. It still informs the standard picture of neutron star production in the Galaxy. We examine herein some recent evidence bearing on this question which has been derived from Observatory X-ray observations of supernova remnants and radio pulsars. In particular, the discovery that X-ray synchrotron nebulae are found surrounding most young ( 10⁶ yr) pulsars observed to date is discussed. We explore the implications of the lack of such nebulae in the majority of supernova remnants (SNR) for the properties and frequency of neutron star formation in supernova events.     

Investigation of magnetospheric processes with the use of a source of strong magnetic field in the ionosphere

More than 20 years ago V.P. Shabansky suggested that the magnetic system installed aboard the satellite, could be used as a physical instrument for studying the processes which occur in the near Earth space. The corresponding space scales of an artificial “magnetosphere”—“magnisphere”—are 10 m in the experiment with relatively small magnets in the ionosphere and 100 m in the solar wind. The corresponding similarity criteria are estimated. The possible scheme of the experiment with a superconducting magnet (magnetic moment 10⁵ A · m²) installed aboard the satellite is considered. The experimental complex includes a number of systems for measuring the fluxes of charged particles in a wide energy range, DC electric and magnetic fields, the electromagnetic fields in different frequency bands (from X-rays to radio). The scientific objectives are discussed in detail.     

Inner core wobble and free core nutation of pulsar PSR B1828-11

PSR B1828-11 has long-term, highly periodic and correlated variations in pulse shape and a slow-down rate with period variations of approximately 1000, 500 and 250 days [Stairs, I.H., Lyne, A.G., Shemar, S.L. Evidence for free precession in a pulsar. Nature 406, 484–486, 2000]. There are three potential explanations of pulses time-of-arrival from a pulsar. These are related to the interior of the neutron star, planetary bodies, free precession and nutation. We use the Hamiltonian canonical method of Getino (1995) for analyzing the dynamically symmetric pulsar PSR B1828-11, consisting of a rigid crust, elliptical liquid outer core and solid inner core. Using the theory of differential rotation of a pulsar, we investigate the dependence on Chandler wobble period, inner core wobble, retrograde free core nutation and prograde free inner core nutation from ellipticity of the inner crystal core, outer liquid core and total pulsar.     

New magnetodynamic principles in cosmic physics

The effect of gravity on super-escape particles spiralling along magnetic field lines need not be negligible when the field lines are long enough and the field-strength variation small. If the magnetic field strength decreases with altitude but only very slowly, some unexpected phenomena may occur owing to gravity: some super-high-velocity particles can possess an upper level of reflection which impedes their escape into higher regions. Some of these “super-escape particles may, however, propagate through the level at which their pitch angle is 90° and continue spiralling in the same direction (“hole” boundary). In addition, the pitch angle of some super-escape particles may only achieve a maximum which can be very small (hole effect). Many plasma phenomena can be derived from these charecteristic features of particle trajectories.     

Optical and X-ray aspects of quasars

We review the present knowledge on the cosmological evolution of quasars, by discussing some of the recent results obtained from studies of optically selected objects. Despite the fast development of prism survey tecniques, the color selection still appears to be the best tecnique for constructing the complete samples which are necessary for statistical studies. It is shown, however, that even the best available complete samples of quasars selected on the basis of ultraviolet excess (z < 2.2) are not sufficient to univocally determine the “correct” evolutionary model. Moreover, some preliminary results suggest that the evolution law derived from quasars with m_B<20 and z<2.2 can not be extrapolated to fainter magnitudes and higher redshifts. On the basis of what is known today about the optical and X-ray properties of quasars, we then discuss some of teh possible results, relevant to cosmology, which can be achieved with future coordinated optical and X-ray observations of quasars.     

Rapid variability of 10–140 keV X-rays from Cygnus X-1

On five occasions in 1977 and 1978, Cygnus X-1 was observed using the Low-Energy Detectors of the UCSD/MIT Hard X-Ray and Low-Energy Gamma-Ray Experiment on the HEAO-1 satellite. Rapid (0.08 s ≤ t ≤ 1000 s) variability was found in the 10 – 140 keV band. The power spectrum was “white” for 10⁻³ Hz < f ≤ 5 × 10⁻² Hz and was proportional to f⁻¹ for 5 × 10⁻² Hz ≤ f < 3 Hz, indicating correlations on all time scales < 20 s. If the emission is produced by Comptonization of a soft photon flux in a hot cloud, the heating of the cloud cannot be constant; it must vary on time scales up to 20 seconds. A variable accretion rate could cause the observed effects.     

Globular cluster origin of X-ray bursters

X-ray bursters and galactic bulge x-ray sources, or the most luminous x-ray sources in the galaxy, are reasonably well constrained in their basic nature but not in their origin. We have suggested they may all have been produced by tidal capture in high density cores of globular clusters, which have now largely been disrupted by tidal stripping and shocking in the galactic plane. General arguments are presented for cluster disruption by the possible ring of giant molecular clouds in the Galaxy. Tests of the cluster disruption hypothesis are in progress and preliminary results are summarized here. The G-K star “companions” previously noted for at least 4 bursters have spectra (in the two cases observed) consistent with metal rich cluster giants. Several possibilities are discussed, including the formation of hierarchical triples in the dissolving cluster or in the galactic plane.     

Collection of cometary dust

Rendezvous Missions to Comets lead to low velocities at the nucleus of the comet. The resulting impact velocity of the cometary dust on a target will range between 10 and 400 m/s. The dust particle which impacts on a target can be collected for a subsequent in-situ analysis.

The collection efficiency of a target depends in addition to obvious geometrical conditions upon the surface of the target. The surface characteristics can be divided into two groups:

• “dirty” surfaces, covered with silicate or hydrocarbon compounds (for example vacuum grease),

• “clean” surfaces, like gold (with additional sputtering).

This paper deals with the experimental and theoretical investigation of the collection efficiency of “clean” targets. Laboratory experiments are described which were conducted at the Technische Universität München, Lehrstuhl für Raumfahrttechnik, and the Max-Planck-Institut für Kernphysik, Heidelberg. In both experiments an electromagnetic accelerator is used to accelerate different types of dust in vacuum to velocities between 10 and 400 m/s.

The target is then examined under the microscope and a secondary ion mass spectrometer (which is a model of the laboratory carried on board of the spacecraft for “in situ” analysis). The adhesion of the dust grains at the target is evaluated experimentally in an ultracentrifuge.     

Mini-belt as a fine spatial structure of the outer radiation belt in quiet and disturbed conditions

Electron flux data from LANL geostationary spacecrafts were statistically treated and ordered in a special magnetic coordinate system (effective L-coordinate and MLT). The data treating procedure allowed to obtain the dynamics of quasi-trapped electrons of different energies on effective L-shells ranging from 6.6 to 7.0. It was found that in quiet conditions a stable fine spatial structure of quasi-trapped electrons exists with maximum of fluxes near L = 6.78 and MLT=12. This structure may be looked at as an asymmetrical “mini-belt”. The position of the maximum depends on electron energy and changes with magnetic activity. The dynamics of this mini-belt for both quiet and disturbed periods is illustrated and discussed. During isolated magnetic storms the mini-belt maximum shifts in a regular manner outward and inward; a diffusion wave of quasi-trapped particles propagates from outside of the geostationary orbit and serves as a source of new particles for the mini-belt. The azimuthal geometry of this diffusion wave extracted from experimental data is illustrated. The possible role of the “mini-belt” is discussed in relation with well-known “anomalous” dynamics of the inner radiation belt.     

Cosmology and GUTs: The matter of the universe

To illustrate the interaction of Grand Unified Theories (GUTs), supersymmetry (SUSY), and cosmology, a worked example is carried out. This example is the dark matter problem, or “What is the dominant matter of the Universe?” It is shown that if GUTs are assumed then the primordial perturbations are probably adiabatic, if inflation is assumed then Ω = 1 and GUTs first name is probably SUSY. If Ω = 1, big bang nucleosynthesis tells us that the bulk of the matter is non-baryonic. SUSY-GUTs gives us some possible candidate inos to which massive neutrinos, axion or planetary mass black holes can be added. These candidates can be classified hot (or warm) or cold types of dark matter. It is shown that hot gives Ω = 1 and naturally gives large scale structure but does not give small scale structure or galaxy formation times, whereas cold gives small scale structure and formation times but cannot easily yield Ω = 1. It is concluded that either a hybrid of both hot and cold or non-random phases for the perturbations may be needed.