Observational signatures of helical jets can be found in some X-ray binaries (XRB), planetary nebulae, Herbig-Haro objects and in jets of active galactic nuclei (AGN). For the prototypical XRB SS433 a kinematic model of precessing jets has been applied very successfully and yielded a determination of its distance which is independent of conventional methods. In galactic jets precession appears ...

Aims. We investigate potential models that could explain why multiple proto-stellar systems predominantly show single jets. During their formation, stars most frequently produce energetic outflows and jets. However, binary jets have only been observed in a very small number of systems. Methods. We model numerically 3D binary jets for various outflow parameters. We also model the propagation of ...

It is commonly accepted that jets have not been observed in cataclysmic variables (CVs) so far. This absence was recently explained by their low mass transfer rates compared with objects with jets. A mass accretion limit for jets in CVs was proposed to be Ṁ ∼ 10−7 − 10−6 M⊙/yr. There was, however, a report of evidence for jets in V1494 Aql, the second nova that erupted in Aquila in 1999. In thi...

Turbulent flows are often observed to be organized into large-spatial-scale jets such as the familiar zonal jets in the upper levels of the Jovian atmosphere. These relatively steady large-scale jets are not forced coherently but are maintained by the much smaller spatialand temporal-scale turbulence with which they coexist. The turbulence maintaining the jets may arise from exogenous sources s...

I derive the condition for narrow jets with varying axis, e.g., precessing jets, to inflate more or less spherical (fat) bubbles in planetary nebulae and clusters of galaxies. This work follows a previous work dealing with wide jets, i.e., having a wide opening angle. The expressions derive here are qualitatively and quantitatively similar to the conditions for inflating fat bubbles by non-prec...

Abstract: From an observational point of view, unveiling the physical processes behind the nature of the jets emanating from radio-loud AGN demands the resolution of the structure across the jet with the highest angular resolutions. Relying on a magneto-fluid dynamical description, numerical simulations can help to characterize the internal structure of jets (transversal structure, magnetic fie...

Synthetic jets--also referred to as mass-less jets--offer the potential of effective, on-demand, fluid-based control of separating boundary layers on highly loaded aerodynamic surfaces, without the need for a mass source. However, the control authority that may optimally be derived from such jets, and any generality of the underlying flow physics are obscured by the wide range of geometric and ...

The production of baryons and K 0 S mesons in quark and gluon jets has been investigated in 3-jet events using 2.8 million hadronic Z 0 decays recorded with the OPAL detector at LEP. The events were selected with various jet nding algorithms resulting in jet samples of somewhat diierent topologies. The jets were classiied according to their energy with the aid of Monte Carlo models: the lowest ...

To Ivan Koll a r on the occasion of his 60th birthday. The usual jets were introduced by C. Ehresmann as a fundamental tool in Diierential Geometry. They permit to globalize the theory of diierential systems and to give a formulation of the \innnite groups" of E. Cartan; this leads to the theory of Lie pseudogroups; initiated by C. Ehresmann, this theory was studied by many mathematicians (the ...

First evidences of IR excess and disk mass accretion (strong Hα emission) around brown dwarfs seem to indicate the existence of circumstellar disks around these sub-stellar objects. Nothing is known at the present time about outflows which potentially might be launched from brown dwarfs, although jets are typically associated with the accretion in standard T Tauri star disks. In this paper we c...