The importance of radiation pressure in the launching of jets
نویسنده
چکیده
Based on the results of applying the extended ADC emission model to three Z-track sources: GX 340+0, GX 5-1 and Cyg X-2, we propose an explanation of the Z-track sources in which the Normal and Horizontal Branches are dominated by the increasing radiation pressure of the neutron star. The emitted flux becomes several times super-Eddington at the Hard Apex and Horizontal Branch and we suggest that the inner accretion disk is disrupted by this and that part of the accretion flow is diverted vertically. This position on the Z-track is exactly the position where radio emission is detected showing the presence of jets. We thus propose that high radiation pressure is a necessary condition for the launching of jets. We also show that flaring must consist of unstable nuclear burning and that the mass accretion rate per unit emitting area of the neutron star ṁ at the onset of flaring agrees well with the critical theoretical value at which burning becomes unstable.
منابع مشابه
Designing and Manufacturing the Multiple Jets Simulator and Experimental Investigation of the Multiple Jets in Crossflow
Designing and manufacturing the multiple jets simulator and experimental investigation of the multiple jets in crossflow at low velocity ratios have been studied Together with design and build a low-speed wind tunnel. A specific rake is used to determine the flow field pressure and changes in static pressure measured by pressure taps in the near field of the jets. There are generally three regi...
متن کاملDesigning and Manufacturing the Multiple Jets Simulator and Experimental Investigation of the Multiple Jets in Crossflow
Designing and manufacturing the multiple jets simulator and experimental investigation of the multiple jets in crossflow at low velocity ratios have been studied Together with design and build a low-speed wind tunnel. A specific rake is used to determine the flow field pressure and changes in static pressure measured by pressure taps in the near field of the jets. There are generally three regi...
متن کاملNumerical Simulation of Free Surface in the Case of Plane Turbulent Wall Jets in Shallow Tailwater
Wall-jet flow is an important flow field in hydraulic engineering, and its applications include flow from the bottom outlet of dams and sluice gates. In this paper, the plane turbulent wall jet in shallow tailwater is simulated by solving the Reynolds Averaged Navier-Stokes equations using the standard turbulence closure model. This study aims to explore the ability of a time splitting method ...
متن کاملNumerical Analysis of Opposed Rows of Coolant Jets Injected into a Heated Crossflow
The mixing characteristics of coolant air jets with the hot gas exiting the gas turbine combustor’s primary zone is of major importance to the combustor exit temperature profile. In the present work, a three dimensional numerical simulation on the basis of the finite volume method was developed. The aim was to investigate the penetration and mixing characteristics of directly opposed rows of co...
متن کاملModelling of Suddenly Expanded Flow Process in Supersonic Mach Regime using Design of Experiments and Response Surface Methodology
The present work is an attempt to model, analyze, and control the flow at the base of an abruptly expanded circular duct by using design of experiments (DOE) and response surface methodology (RSM). Tiny-jets in the form of orifice were positioned at an interval of 900, 6.5 mm from the primary axis of the main jet of the nozzle. Experiments were conducted to measure two responses namely, base pr...
متن کامل