![]() Radio-loud narrow-line Seyfert galaxies are in general mild relativistic The help of the radiation force, the mass loss rate in the outflow is high, Magnetic field and radiation force of the accretion disk. Investigate the outflows accelerated from the hot corona above the disk by the Related to hot plasma in some X-ray binaries and active galactic nuclei. Implies that hot gas (probably in the corona) is necessary for launching a jetįrom the radiation pressure dominated disk, which provides a naturalĮxplanation on the observational evidence that the relativistic jets are For the latter case, the slow sonic point in the outflow may probablyīe in the disk, which leads to a slow circular dense flow above the disk. Of the radiation pressure dominate disk only if the effective potential barrierĪlong the magnetic field line is extremely shallow or no potential barrier is This means that the outflow can be launched magnetically from the photosphere Significantly lower than that of a gas pressure dominated disk, \Theta (H/r)^2. We estimate the surface temperature of a radiation pressureĭominated accretion disk, \Theta=(c_s/r\Omega_K)^2<<(H/r)^2, which is The inner region of a luminous accretion disk is radiation pressureĭominated. ![]() Progress towards understanding massive star formation, considering physical andĬhemical processes, comparisons with low and intermediate-mass stars, and We review recent theoretical and observational Very high near the cluster center, then collisions between stars may also help Proceed hand in hand with star cluster formation. In this case, massive star formation must InĬompetitive Accretion, the material that forms a massive star is drawn moreĬhaotically from a wider region of the clump without passing through a phase ofīeing in a massive, coherent core. Mass function has a similar form to the stellar initial mass function. To form a single star or a small-N multiple. ![]() They then undergo relatively ordered collapse via a central disk Initial conditions are self-gravitating, centrally concentrated cores thatĬondense with a range of masses from the surrounding, fragmenting clumpĮnvironment. Two main classes of massive star formation theory are underĪctive study, Core Accretion and Competitive Accretion. The evolution of galaxies, to the regulation of the interstellar medium, to theįormation of star clusters, and even to the formation of planets around stars Vast range of scales and processes, from the reionization of the universe, to The enormous radiative and mechanical luminosities of massive stars impact a Luminosity) increases (with age), the outflows become less collimated. Thus, we have shown that when the stellar mass (thus Essentially, our parameter runs withĭifferent stellar mass can be understood as a proxy for the time evolution of Pressure is too small to have much impact. Unless the disk extends very close to the star, its We find that it is mainly the stellar radiation whichĪffects the jet dynamics. Small change in the line-force parameter 'alpha' from 0.60 to 0.55 changes the Increases from 20 deg to 32 deg for stellar masses from 20 Msun to 60 Msun. Substantial de-collimation of 35 % due to radiation forces. For our reference simulation - assuming a 30 Msun star, we find We perform a parameter study consideringĭifferent stellar masses (thus luminosity), magnetic flux, and line-force MHD effects from radiative forces, we start the simulation in pure MHD, and Region (r < 50 AU) by magneto-centrifugal acceleration. We launch the outflow from the innermost disk We have modified the PLUTO code to include radiative forces in the Particularly considering the radiation pressure exerted by the star and theĭisk. Investigates various physical processes that impacts the outflow dynamics, i.e. I am aware there is also a Mach-based RR formula and it has the same problem.Observations indicate that outflows from massive young stars are moreĬollimated during their early evolution compared to later stages. I also can't find any space shuttle telemetry to corroborate the TAS assumptions I made above. ![]() So are these RR=TAS²/87 formulas assuming to be used below a specific altitude? I can't find anything for orbit or reentry. which makes no sense because there are practically no molecules of air to hit! Therefore, my TAT (OAT plus ram rise) is in the thousands of degrees Kelvin. They do not appear to take into account the static pressure or atmospheric composition, only the adiabatic index. My assumption is that if I am in orbit say at 120 km altitude with an instantaneous velocity of 8 km/s my TAS would be fairly close to 8 km/s even though my Indicated Airspeed (IAS) shows zero.Īssuming the above holds true, the "ram rise" (RR) formulas I find are all based on Mach (which, in turn, is based on TAS) or TAS directly. True Airspeed (TAS) is the vehicle speed relative to the surrounding air.
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