Related papers: Ionizing wave via high-power HF acceleration
High-mass stars form in much richer environments than those associated with isolated low-mass stars, and once they reach a certain mass, produce ionised (HII) regions. The formation of these pockets of ionised gas are unique to the…
We combine parallax distances to nearby O stars with parsec-scale resolution three-dimensional dust maps of the local region of the Milky Way (within 1.25 kpc of the Sun) to simulate the transfer of Lyman continuum photons through the…
We describe a method for removing ionospheric effects from single-frequency radio data a posteriori. This method is based on a theoretical climatological model developed by the USAF, which returns electron density as a function of position…
We characterize the problem of artificial polarization for the Submillimeter High Angular Resolution Polarimeter (SHARP) through the use of simulated data and observations made at the Caltech Submillimeter Observatory (CSO). These…
We present the results of a 2-D, two fluid (ions and neutrals) simulation of the ambipolar filamentation process, in which a magnetized, weakly ionized plasma is stirred by turbulence in the ambipolar frequency range. The higher turbulent…
During periods of intense geomagnetic activity, strong electric fields and currents penetrate from the magnetosphere into high-latitude ionosphere where they dissipate energy, form electrojets, and excite plasma instabilities in the…
The ionization efficiency of helicon plasma discharge is explored by changing the low axial magnetic field gradients near the helicon antenna. The highest plasma density is found for a most possible diverging field near the antenna by…
Recent in situ observations from Parker Solar Probe (PSP) near perihelia reveal ion beams, temperature anisotropies, and kinetic wave activity. These features are likely linked to solar wind heating and acceleration. During PSP Encounter 17…
Magnetic-field generation by a relativistic ion beam propagating through an electron-ion plasma along a homogeneous magnetic field is investigated with 2.5D high-resolution particle-in-cell (PIC) simulations. The studies test predictions of…
Observations of resolved HeII Lyman alpha absorption in spectra of two QSO's suggest that the epoch of helium ionization occurred at z~3. Proximity zones in the spectra of the quasars (z=3.18, 3.285) at 304 A resemble Stromgren spheres,…
We consider the generation of electric currents in the solar chromosphere where the ionization level is typically low. We show that ambient electrons become magnetized even for weak magnetic fields (30 G); that is, their gyrofrequency…
The ionization of atoms with sequences of attosecond pulses gives rise to excited ionic states that are entangled with the emitted photoelectron. Still, the ionic ensemble preserves some coherence that can be controlled through the laser…
Injection process of pickup ion acceleration at a heliospheric termination shock is investigated. Using two-dimensional fully kinetic particle-in-cell simulation, accelerated pickup ions are self-consistently reproduced by tracking long…
A two-dimensional model atom is employed to study the ionization behavior of initially excited atomic states in highly-frequent intense laser pulses beyond the dipole approximation. An additional regime of ionization suppression is found at…
Some essential features of the ion plasma wave in both kinetic and fluid descriptions are presented. The wave develops at wavelengths shorter than the electron Debye radius. Thermal motion of electrons at this scale is such that they…
We suggest an explanation for the high-frequency power excess surrounding active regions known as seismic halos. The idea is based on numerical simulations of magneto-acoustic waves propagation in sunspots. We propose that such an excess…
In this study, the dynamic of guided ionization wave (IW) generated by an atmospheric pressure plasma jet (APPJ) device in plasma gun configuration is experimentally investigated. The present work focuses on the properties of the intense…
We study the formation of a partially ionized zone behind the usual H II zone in photo-ionized gas for gas density intermediate between ordinary H II regions and AGN BLRs and without X-rays. While Lyman continuum photons are depleted before…
A long laser beam propagating through an underdense plasma produces a positively charged ion channel by expelling plasma electrons in the transverse direction. We consider the dynamics of a test electron in a resulting two-dimensional…
The temperature of the low-density intergalactic medium is set by the balance between adiabatic cooling resulting from the expansion of the universe, and photo-heating by the UV-background. A sudden injection of entropy from the…