Broadband X-ray data of five magnetars show that their hard X-ray pulses suffer periodic phase modulations, at a period ∼ 104 times their pulse period. The phenomenon is interpreted as a result of free precession of neutron stars that are prolately deformed to an asphericity of ∼ 10−4, by the magnetic stress of toroidal fields reaching ∼ 1016 G. The behavior is absent in their soft X-ray pulses, probably due to a higher emission symmetry. The ultra-high toroidal fields, considered common to magnetars, may persist longer than their dipole fields.

It was shown (Faenov et al., 2015b) that the energy of femtosecond laser pulses with relativistic intensity approaching to ~1021 W/cm2 is efficiently converted to X-ray radiation and produces exotic states in solid density plasma periphery. We propose and show by one-dimensional two-temperature hydrodynamic modeling, that applying two such unique ultra-bright X-ray sources with intensities above 1017 W/cm2 – allow to generate shock waves with strength of up to some hundreds Mbar, which could give new opportunities for studies of matter in extreme conditions.

The use of laboratory experiments as plasma creating sources is a valuable tool for understanding astrophysical observations. Recently plasma created through irradiation by lasers with relativistic intensities has been used to study effects of hot electrons and X-ray pumping on X-ray formation of multiply charged ions spectra. This paper discusses the formation of K-shell Fe spectra recorded from a plasma irradiated by 35 fs pulses with intensities of 1021 W/cm2. Modeling of the spectra suggests three different regions of plasma radiation including a cold ~10 eV region, a mild ~700 eV region, and a hot ~3500 eV region. The influence of hot electrons and X-ray pumping is discussed and a comparison with K-shell Fe spectra from a 1 MA X-pinch experiment is included to highlight the differences due to the shorter time frame of the laser–plasma interaction experiment.

Jets have been observed from both neutron stars and black holes in binary X-ray sources. The neutron star jets are typically 30 times weaker than the black-hole ones. Thus, the second have been studied more extensively. Contrary to common belief, jets from compact X-ray sources are not simply “fireworks” that emit radio waves. I will demonstrate that they play a central role in the observed phenomena in both neutron star and black-hole systems. In particular, for black-hole jets, a simple jet model can explain the very stringent correlations that have been found between the power-law X-ray spectrum and a) the time lag between hard and soft X-rays and b) the characteristic frequencies observed in the power spectra. Up to now, no other model has even attempted to explain these correlations. I will present the weaknesses of the model and the improvements that need to be done to it.

The chlorine Heα radiation of polyvinyl chloride (PVC) was investigated with respect to X-ray scattering experiments on dense plasmas. The X-ray source was a laser-produced plasma that was observed with a highly reflective highly oriented pyrolytic graphite (HOPG) crystal spectrometer as it is used in current x-ray scattering experiments on dense plasmas. The underlying dielectronic satellites of Heα cannot be resolved, therefore the plasma was observed at the same time with a focusing spectrometer with spatial resolution. To reconstruct the spectrum a simple model to calculate the spectral line emission based on dielectronic recombination and inner shell excitation of helium- and lithium-like ions was used. The analysis shows that chlorine dielectronic satellite emission is intense compared to Heα in laser-produced chlorine plasmas with a temperature of 300 eV in this wavelength range of Δλ = 0.07 Å (ΔE = 43 eV). The method proposed in this paper allows deducing experimentally the role of the underlying dielectronic satellites in the scatter spectrum measured with a HOPG crystal spectrometer. It is shown that the dielectronic satellites can be neglected when the scattering is measured with low spectral resolution in the non-collective regime. They are of major importance in the collective scatter regime where a high spectral resolution is necessary.

Laser matter interaction in the regime of super-intense and ultra-short laser pulses is discovering common interests and goals for plasma and elementary particles physics. Among them, the electron laser wakefield acceleration and the X/γ tunable sources, based on the Thomson scattering (TS) of optical photons on accelerated electrons, represent the most challenging applications. The activity of the Intense Laser Irradiation Laboratory in this field will be presented.

We suggest that the ultraluminous X-ray sources located in external galaxies (ULXs) are supercritical accretion disks like that in SS433, observed close to the disk axis. We estimate parameters of the SS433 funnel, where the relativistic jets are formed. Emergent X-ray spectrum in the proposed model of the multicolor funnel (MCF) is calculated. The spectrum can be compared with those of ULXs. We predict a complex absorption-line spectrum with broad and shallow K$\alpha$/Kc blends of the most abundant heavy elements and particular temporal variability. Another critical idea comes from observations of nebulae around the ULXs. We present results of 3D-spectroscopy of nebulae of two ULXs located in Holmberg II and NGC6946. In both cases the nebula is found to be powered by the central black hole. The nebulae are compared with SS433 nebula (W50).

The absolutely calibrated K-shell spectra emitted from short-living aluminum plasmas at laser intensities of 5 × 1015–4 × 1018 W/cm2 are reported. The experiments performed with the constant energy, variable-length laser pulses (1.5 ps–1 ns) are modeled by the one-dimensional (1D) hydrodynamics code, including nonlinear resonance absorption of the laser radiation, fast electron acceleration, and energy transfer into the target. The characteristic features of the measured and the postprocessed spectra are outlined. The spatial and temporal profiles of the emitted spectra are presented; the scaling rules for the conversion efficiency of the laser radiation into the line X-ray emission are discussed.

High-mass X-ray binaries (HMXBs) represent an important stage in the evolution of massive binary systems. The compact object (in most cases an X-ray pulsar) not only provides information on the orbital and stellar parameters, but also probes the stellar wind of the massive companion, an OB supergiant or Be star. The X-ray luminosity directly depends on the density and the velocity of the wind at the orbit of the X-ray source. Important constraints on the stellar-wind structure can be set by studying the orbital modulation of UV P-Cygni profiles. In this paper different aspects of the interactive wind-accretion process are highlighted, such as the highly variable X-ray luminosity, the influence of the X-rays on the radiative acceleration of the wind inside the ionization zone, and the large-scale structures that trail the X-ray source in its orbit.