Related papers: Cold electrons at comet 67P/Churyumov-Gerasimenko
Comet 67P/Churyumov-Gerasimenko (67P) become observable for the first time in 2021 since the Rosetta rendezvous in 2014--16. Here, we present pre-perihelion polarimetric measurements of 67P from 2021 performed with the Very Large Telescope…
In this short note, we present some work on investigating electron temperatures and potentials in steady or unsteady dilute plasma flows. The analysis is based on the detailed fluid model for electrons. Ionization, normalized electron…
Infrared observations of the coma of 67P/Churyumov-Gerasimenko were carried out from July to September 2015, i.e., around perihelion (13 August 2015), with the high-resolution channel of the VIRTIS instrument onboard Rosetta. We present the…
The non-equilibrium dynamics of electrons is of a great experimental and theoretical value providing important microscopic parameters of the Coulomb and electron-phonon interactions in metals and other cold plasmas. Because of the…
Kuiper belt objects, such as Arrokoth, the probable progenitors of short-period comets, formed and evolved at large heliocentric distances, where the ambient temperatures appear to be sufficiently low for preserving volatile ices. By…
Electron heating in an ultracold neutral plasma is modeled using classical molecular dynamics simulations in the presence of an externally applied magnetic field. A sufficiently strong magnetic field is found to reduce disorder induced…
Hubble Space Telescope observations of interstellar comet 2I/Borisov near perihelion show the ejection of large (>~100 um) particles at <~9 m/s speeds, with estimated mass-loss rates of ~35 kg/s. The total mass loss from comet Borisov…
We examine plasma composition of jets in active galactic nuclei through the comparison of the total pressure ($P$) with partial pressures of electrons and protons in a cocoon. The total pressure is estimated from the analysis of an…
In the collisionless plasmas of radiatively inefficient accretion flows, heating and acceleration of ions and electrons is not well understood. Recent studies in the gyrokinetic limit revealed the importance of incorporating both the…
A new method for measuring the electron temperature of the plasma in GOL-NB facility is proposed. The proposed method is based on measuring the ratio of intensities of spectral lines emitted by fast atoms injected into the plasma. The beams…
We consider weakly ionized plasma where frequent elastic scattering of electrons on neutrals change the individual acts and the rate of electron-electron collisions significantly. In this case, the kinetics of electron thermalization is…
Ultracold neutral plasmas are formed by photoionizing laser-cooled atoms near the ionization threshold. Through the application of atomic physics techniques and diagnostics, these experiments stretch the boundaries of traditional neutral…
On 3 July 2016, several instruments on board ESA's Rosetta spacecraft detected signs of an outburst event on comet 67P, at a heliocentric distance of 3.32 AU from the sun, outbound from perihelion. We here report on the inferred properties…
We present VLT/MUSE observations of comet 67P/Churyumov-Gerasimenko during its 2021 perihelion passage, from which we generated simultaneous maps of dust, [OI], C$_2$, NH$_2$, and CN comae across 12 pre- and post-perihelion epochs. These…
Thermal instability in an electron-ion magnetized plasma, which is relevant in the intragalactic medium (IGM) of galaxy clusters, solar corona, and other two-component plasma objects is investigated. We apply the multicomponent plasma…
Cometary outbursts offer a valuable window into the composition of comet nuclei with their forceful ejection of dust and volatiles in explosive events, revealing the interior components of the comet. Understanding how different types of…
Rosetta observations of 67P/Churyumov-Gerasimenko (67P) reveal that most changes occur in the fallback-generated smooth terrains, vast deposits of granular material blanketing the comet's northern hemisphere. These changes express…
The neutrino cooling and gamma heating rates are considered as an important input needed to study the final phases of the evolution of high-mass stars. The weak-interaction mediated processes, namely the $\beta$-decay and electron capture,…
Photoionization by high-energy photons creates nonthermal electrons with a broad range of energies that heat and chemically transform the atmospheres of planets. The specifics of the interactions are notably different when the gas is atomic…
The data obtained in the recent Rosetta space mission to comet 67P/Churyumov-Gerasimenko have had a profound impact on the understanding of the nature of comets. In addition to revising the notions on the physical properties and structure…