Related papers: Conditions for supersonic bent Marshak waves
Total and internal energy requirements set constraints on the allowable temperature on the disk. In a gas pressure dominated disk, they lead to a cooling rate that decreases with temperature. These findings are used to show that the flow is…
We study the problem of radiative heat (Marshak) waves using advanced approximate approaches. Supersonic radiative Marshak waves that are propagating into a material are radiation dominated (i.e. hydrodynamic motion is negligible), and can…
We present a systematic study of the similarity solutions for the Marshak wave problem, in the local thermodynamic equilibrium (LTE) diffusion approximation and in the supersonic regime. Self-similar solutions exist for a temporal power law…
If certain conditions are met, a propagating phase boundary can be a sonic horizon. Sonic Hawking radiation from such a phase boundary is expected in the quantum theory. The Hawking temperature for typical values of system parameters can be…
Similarity solutions to the nonlinear non-equilibrium Marshak wave problem with a time dependent radiation driving source are presented. The radiation transfer model used is the gray, non-equilibrium diffusion approximation in the…
This article studies the propagation of supersonic radiative Marshak waves. These waves are radiation dominated, and play an important role in inertial confinement fusion and in astrophysical and laboratory systems. For that reason, this…
Irradiating materials with ultra-short laser pulses generates unwanted shock waves which distort the interesting physics. Advanced boundary conditions are presented to erase even very strong shock waves. Depending on the wave length, laser…
One can use transsonic Bose-Einstein condensates of alkali atoms to establish the laboratory analog of the event horizon and to measure the acoustic version of Hawking radiation. We determine the conditions for supersonic flow and the…
We describe the characterization of a pulsed supersonic rare gas beam which is intended to serve as an ultracold neutral atom target for the production of an ultrashort ion pulse via femtosecond photoionization. The velocity distribution of…
Accurate temperature calculations for circumstellar disks are particularly important for their chemical evolution. Their temperature distribution is determined by the optical properties of the dust grains, which, among other parameters,…
A superfluid atomic gas is prepared inside an optical resonator with an ultra-narrow band width on the order of the single photon recoil energy. When a monochromatic off-resonant laser beam irradiates the atoms, above a critical intensity…
Balloon-borne telescopes present unique thermal design challenges which are a combination of those present for both space and ground telescopes. At altitudes of 35-40 km, convection effects are minimal and difficult to characterize.…
Transition radiation from relativistic electrons is investigated in an ultrasonic superlattice excited in a finite thickness plate. In the quasi-classical approximation formulae are derived for the vector potential of the electromagnetic…
Two approaches (micro- and macro- investigations) are used to determine the dimension dependences of the optical parameters of the nanometer-scale layers of materials. It is shown that both an index of refraction and coefficient of…
We investigate diffusion in supersonic, turbulent, compressible flows. Supersonic turbulence can be characterized as network of interacting shocks. We consider flows with different rms Mach numbers and where energy necessary to maintain…
A 10 meter diameter submillimeter-wave telescope has been proposed for the NSF Amundsen-Scott South Pole Station. Current evidence indicates that the South Pole is the best submillimeter-wave telescope site among all existing or proposed…
Numerical implementation of a theory yields acoustic wave packets whose peak-to-peak speeds, $c_{3d}$, are supersonic in a dispersionless medium due to temporal interference between direct and boundary-reflected paths. The effect occurs…
We study heat conduction in a one-dimensional {finite}, unpinned chain of atoms perturbed by stochastic momentum exchange and coupled to Langevin heat baths at {possibly} distinct temperatures placed at the endpoints of the chain. While…
We have derived the radiative-transfer equation for a point source with a specified intensity and spectrum, originating in the early Universe between the epochs of annihilation and recombination, at redshifts $z_\s =10^8\div 10^4$. The…
We study the propagation of radiative heat (Marshak) waves, using modified $P_1$-approximation equations. In relatively optically-thin media the heat propagation is supersonic,~i.e. hydrodynamic motion is negligible, and thus can be…