Dynamic and stagnating plasma flow leading to magnetic-flux-tube collimation.
نویسندگان
چکیده
Highly collimated, plasma-filled magnetic-flux tubes are frequently observed on galactic, stellar, and laboratory scales. We propose that a single, universal magnetohydrodynamic pumping process explains why such collimated, plasma-filled magnetic-flux tubes are ubiquitous. Experimental evidence from carefully diagnosed laboratory simulations of astrophysical jets confirms this assertion and is reported here. The magnetohydrodynamic process pumps plasma into a magnetic-flux tube and the stagnation of the resulting flow causes this flux tube to become collimated.
منابع مشابه
Plasma tubes becoming collimated as a result of magnetohydrodynamic pumping
Collimated magnetized plasma structures are commonly observed on galactic, stellar, and laboratory scales. The Caltech plasma gun produces magnetically driven plasma jets bearing a striking resemblance to astrophysical jets and solar coronal loops by imposing boundary conditions analogous to those plasmas. This paper presents experimental observations of gun-produced plasma jets that support a ...
متن کاملMagnetically driven flows in arched plasma structures.
Laboratory experiments demonstrate high-speed plasma flows from both footpoints of arched magnetic flux tubes, resulting in bulk plasma transport into the flux tube and persistent axial collimation even as the flux tube lengthens and kinks. The measured flows are in agreement with the predictions of hoop force and collimation models involving fundamental MHD forces. These forces are expected to...
متن کاملExperimental Study on the Effect of Magnetic Field on Critical Heat Flux of Ferrofluid Flow Boiling in a Vertical Tube
In the present work, the critical heat flux measurements were performed for the subcooled flow boiling of pure water and magnetic nanofluids (i.e., water + 0.01 and 0.1 vol.% Fe3O4) in a vertical tube. The effect of applying an external magnetic field on the CHF variation was studied experimentally as well. The obtained results indicated that the subcooled flow boiling CHF in the vertical tub...
متن کاملSimulating Astrophysical Jets in Laboratory Experiments
Pulsed power technology and appropriate boundary conditions have been used to create simulations of magnetically driven astrophysical jets in a laboratory experiment. The experiments are quite reproducible and involve a distinct sequence. Eight initial flux tubes, corresponding to eight gas injection locations, merge to form the jet which lengthens, collimates, and eventually kinks. A model dev...
متن کاملAcceleration and collimation of relativistic plasmas ejected by fast rotators
A stationary self-consistent outflow of a magnetised relativistic plasma from a rotating object with an initially monopole-like magnetic field is investigated in the ideal MHD approximation under the condition σ/U 0 > 1, where σ is the ratio of the Poynting flux over the mass energy flux at the equator and the surface of the star, with U0 = γ0v0/c and γ0 the initial four-velocity and Lorentz fa...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Physical review letters
دوره 95 4 شماره
صفحات -
تاریخ انتشار 2005