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The free electron model with Boltzmann statistics for spherical low-density plasmas (Scientific Reports 9. 20384, 2019) is developed further by numerical calculations with asymptotic relations obtaining the density of electrons, mass…

General Physics · Physics 2021-03-10 Y. Ben-Aryeh

We show that static and oscillating photon bubbles can be excited by diffused light in the laser cooled matter confined in a magneto-optical trap (MOT). The bubble instability is due to the coupling between the radiation field and the mean…

Atomic Physics · Physics 2013-03-28 J. T. Mendonca , R. Kaiser

The overshooting convective motions in the solar photosphere are frequently proposed as the source for the excitation of Alfv\'en waves. However, the photosphere is a) very weakly ionized, and, b) the dynamics of the plasma particles in…

Astrophysics · Physics 2009-11-13 J. Vranjes , S. Poedts , B. P. Pandey , B. De Pontieu

We investigate superradiance of an ensemble of atoms coupled to an integrated superconducting LC-circuit. Particular attention is paid to the effect of inhomogeneous coupling constants. Combining perturbation theory in the inhomogeneity and…

Quantum Physics · Physics 2015-03-18 Daniel Braun , Jonathan Hoffman , Eite Tiesinga

The early part of a supernova (SN) light-curve is dominated by radiation escaping from the expanding shock-heated progenitor envelope. For polytropic Hydrogen envelopes, the properties of the emitted radiation are described by simple…

High Energy Astrophysical Phenomena · Physics 2017-04-12 Nir Sapir , Eli Waxman

Supersonic beams are a prevalent source of cold molecules utilized in the study of chemical reactions, atom interferometry, gas-surface interactions, precision spectroscopy, molecular cooling and more. The triumph of this method emanates…

An overdense plasma layer irradiated by an intense light can exhibit dramatic nonlinear-optical effects due to a relativistic mass-effect of free electrons: highly-multiple hysteresises of reflection and transition, and emergence of…

Plasma Physics · Physics 2010-03-16 A. E. Kaplan

Hydrogen electron cyclotron resonance ion sources plasma measurements based on simple optical emission spectroscopy on a new compact low current ion source designed and built by the authors is presented. By observing the plasma luminescence…

Using three-dimensional particle-in-cell simulations we show that a strongly nonlinear plasma wave excited by an ultrahigh intensity laser pulse works as a compact high-brightness source of X-ray radiation. It has been recently suggested by…

Optics · Physics 2007-05-23 S. Kiselev , A. Pukhov , I. Kostyukov

The interaction of atomic clusters with short, intense pulses of laser light to form extremely hot, dense plasmas has attracted extensive experimental and theoretical interest. The high density of atoms within the cluster greatly enhances…

Atomic Physics · Physics 2009-11-11 Zachary B. Walters , Robin Santra , Chris H. Greene

The intrinsic Lyman-alpha emission lines of normal galaxies before reionization are much absorbed by the damping wing of the Gunn-Peterson trough, rendering their direct detection nearly impossible, if their intrinsic line widths are less…

Astrophysics · Physics 2009-11-07 Renyue Cen

The interaction of an ensemble of atoms with common vacuum modes may lead to an enhanced emission into these modes. This phenomenon, known as superradiance, highlights the coherent nature of spontaneous emission, resulting in macroscopic…

We present a new model of large-scale multilayer convection in solar type stars. This model allows us to understand such self-similar structures observed at solar surface as granulation, supergranulation and giant cells. We study the…

Solar and Stellar Astrophysics · Physics 2010-12-17 E. A. Bruevich , I. K. Rozgacheva

Sources of high-energy photons have important applications in almost all areas of research. However, the photon flux and intensity of existing sources is strongly limited for photon energies above a few hundred keV. Here we show that a…

Ultracold neutral plasmas, formed by photoionizing laser-cooled atoms near the ionization threshold, have electron temperatures in the 1-1000 kelvin range and ion temperatures from tens of millikelvin to a few kelvin. They represent a new…

Atomic Physics · Physics 2009-11-13 T. C. Killian , T. Pattard , T. Pohl , J. M. Rost

Massive stars form in dense and massive molecular cores. The exact formation mechanism is unclear, but it is possible that some massive stars are formed by processes similar to those that produce the low-mass stars, with accretion/ejection…

Astrophysics · Physics 2008-11-26 A. T. Araudo , G. E. Romero , V. Bosch-Ramon , J. M. Paredes

Collision of laser-driven subrelativistic high density ion flows provides a way to create extremely compressed ion conglomerates and study their properties. This paper presents a theoretical study of the electrodynamic implosion of ions…

Plasma Physics · Physics 2025-12-03 S. Yu. Guskov , Ph. Korneev , M. Murakami

A Chandra ACIS-S imaging observation of the nearby galaxy M81 (NGC 3031) reveals 9 luminous soft X-ray sources. The local environments, X-ray spectral properties, and X-ray light curves of the sources are presented and discussed in the…

Astrophysics · Physics 2009-11-07 Douglas Swartz , Kajal Ghosh , Valery Suleimanov , Allyn Tennant , Kinwah Wu

The inelastic light scattering in a 2-d electron gas is studied theoretically using the Boltzmann equation techniques. Electron-hole excitations produce the Raman spectrum essentially different from the one predicted for the 3-d case. In…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 E. G. Mishchenko

Nature's most powerful high-energy sources are capable of accelerating particles to high energy and radiate it away on extremely short timescales, even shorter than the light crossing time of the system. It is yet unclear what physical…

Plasma Physics · Physics 2022-01-03 Luca Comisso , Lorenzo Sironi