相关论文: Estimating the propagation of a uniformly accelera…
We study the evolution of one-dimensional relativistic jets, using the exact solution of the Riemann problem for relativistic flows. For this purpose, we solve equations for the ideal special relativistic fluid composed of dissimilar…
It has been recently discovered that spatially separated Herbig-Haro objects, once considered unrelated, are linked within a chain that may extend for parsecs in either direction of the embedded protostar forming a "giant Herbig-Haro jet".…
We investigate the dynamics of a "bungee-jumper" jet induced by an impulsive force, which retracts after reaching its peak extension. Despite the strongly extensional and highly nonequilibrium nature of this motion, the jet exhibits simple…
Relativistic jets reside in high-energy astrophysical systems of all scales. Their interaction with the surrounding media is critical as it determines the jet evolution, observable signature, and feedback on the environment. During its…
We address the issue of ambipolar diffusion in Herbig-Haro jets. The current consensus holds that these jets are launched and collimated via MHD forces. Observations have, however, shown that the jets can be mildly to weakly ionized.…
We present a ballistic description of the propagation of the working surface of a relativistic jet. Using simple laws of conservation of mass and linear momentum at the working surface, we obtain a full description of the jet flow…
We present a comprehensive analytic model of relativistic jet propagation in expanding homologous media (ejecta). This model covers the entire jet evolution as well as a range of configurations that are relevant to binary neutron star…
We present fully three-dimensional hydrodynamical simulations of radiative cooling jets propagating into stratified isothermal ambient media with power-law density and pressure distributions. The parameters used are mainly suitable for…
Herbig-Haro jets often show some degree of curvature along their path, in many cases produced by the ram pressure of a side-wind. We present simulations of both laboratory and astrophysical curved jets and experimental results from…
The overall properties of the Herbig-Haro objects such as centerline velocity, transversal profile of velocity, flow of mass and energy are explained adopting two models for the turbulent jet. The complex shapes of the Herbig-Haro objects,…
Detailed comparisons are made between observations of scattered light upstream of the head of the HH~1 jet and predictions of simple scattering models. It is shown that, in order to unambiguously determine the velocity of the head of the…
In order to find a law characterising the decrease of velocity along a jet, five analytical methods are suggested. The first two simple models examine the variation of velocity in the presence of Newton's or Stoke's resistance. The equation…
We present an analytical solution of a highly magnetized jet/wind flow. The left side of the general force-free jet/wind equation (the "pulsar" equation) is separated into a rotating and a nonrotating term. The two equations with either…
The line emission from a growing number of Herbig-Haro jets can be observed and resolved at angular distances smaller than a few arcseconds from the central source. The interpretation of this emission is problematic, since the simplest…
We present a set of high-resolution 3D MHD simulations of steady light, supersonic jets, exploring the influence of jet Mach number and the ambient medium on jet propagation and energy deposition over long distances. The results are…
Comparing the properties AGN and Herbig-Haro jets can be a useful exercise for understanding the physical mechanisms at work in collimated outflows that propagate in such different environments. In the case of Herbig-Haro jets, the presence…
A fluorescent image analysis procedure to determine the distribution of species concentration and density in a gas flow is proposed. The fluorescent emission is due to the excitation of atoms/molecules of a gas that is intercepted by an…
We investigate the role discrete clumps embedded in an astrophysical jet play on the jet's morphology and line emission characteristics. By varying clumps' size, density, position, and velocity, we cover a range of parameter space motivated…
Many natural and engineering systems involve the mixing of two fluid streams, in which the effects of density and viscosity gradients play important roles in determining flow stability. We perform linear stability calculations for a jet…
Herbig-Haro (HH) jets are commonly thought of as homogeneous beams of plasma traveling at hypersonic velocities. Structure within jet beams is often attributed to periodic or ``pulsed'' variations of conditions at the jet source.…