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11-03-2007
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#1 (permalink)
| | Understanding |
Plasma Z-Pinch dynamics | |
11-03-2007
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#2 (permalink)
| | Resident Bright |
Re: Plasma Z-Pinch dynamics Quote:
Originally Posted by Pluto
In my opinion the Z-pinch dynamics within plasma may explain the driving force and properties within jets from compact stars and the so called ultra dense compact cores that some people call black holes.
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If that is the case, does the "driving force" described by Z-pinch dynamics determine the rotational curves exhibited by galaxies (or the radial velocity of its components)?
If so, how?
I must have missed that in the link(s).
CC
---------------- Coldcreation | |
11-04-2007
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#3 (permalink)
| | Understanding |
Re: Plasma Z-Pinch dynamics Hello CC
I would assume it does. We need a field scientist to confirm and answer your question.
Plasma properties is one field that requires much research and cash flow backing by politics.
It has always been in the back of my mind.
What process creates the jets in all compacted cores including our sun.
I'm going to post a thread from another forum, if this is not allowed than I will understand.
Quote from Michael Mozina EU Theory and Plasma Cosmology - Forums powered by UBBThreads™ Quote:
My intent in creating this thread on EU theory and plasma cosmology is begin a discourse on EU theory that stays within the framework of current cosmology concepts to as great an extent as possible.
I would like to begin this discussion on EU theory by taking a historical look at some of the early pioneering work that was done on EU theory by Dr. Kristian Birkeland in the early 1900's. Kristian Birkeland - Wikipedia, the free encyclopedia On Possible Electric Phenomena in Solar Systems and Nebulae Plasma cosmology - Wikipedia, the free encyclopedia
Birkeland was fascinated with the Aurora Borealis, so much so that he went on an expedition and traversed the northern polar regions to methodically study and measure the currents that produce these atmospheric discharges.
He eventually came to the conclusion that the sun and the earth are electromagnetically interconnected, and that electrical currents flowed from the sun, and through the earth. It was not until the 1970's that a spacecraft was finally able demonstrate the existence of Birkeland currents inside of our solar system. Space Weather Center Cluster And Double Star Witness A New Facet Of Earth's Magnetic Behaviour
We are now starting to realize that these electrical currents are linked to and are at least partially responsible for storms on the earth and for "sprites" that we see go from clouds to space during some storms. Confirmation of the relationship between the formation of the auroral bulge and Giant Lightning to Space
More recently we have confirmed the existence of very large scale Birkeland currents outside of our solar system. Universe Today » Magnetic Slinky in Space
These same forces seem to also play a critical role in solar system formation: NASA - Baby Star is Way Ahead of its Time
These electric currents are ultimately carried through plasma, which is why I included Plasma Cosmology in this discussion. IMO these two ideas go hand in hand.
Plasma is an excellent conductor of electrical currents. Space as we understand it not actually empty. Instead it is permiated by hydrogen plasma and other forms of plasma. Space as we think of it is not truly "empty", but rather it is filled with plasma, complete with "webs' of interacting electrical currents. Electric Currents
Some examples of these currents inside our solar system include the northern lights of our own planet, but these visual effects of current flow form on every planet. Solar Wind Whips Up Auroral Storms On Jupiter And Saturn Hundreds Of Auroras Detected On Mars
In a very real way, our whole solar system and indeed the whole physical universe is electromagnetically interconnected every bit as much as it is connected by gravity. In fact there is new evidence that gravity itself may simply be an electromagnetic phenomenon. Anti-gravity Effect? Gravitational Equivalent Of A Magnetic Field Measured In Lab | other links BaPSF Image Gallery
The reason why I have posted so many links is for people to understand.
Maybe too much for now. Sorry | |
07-28-2008
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#4 (permalink)
| | Understanding |
Re: Plasma Z-Pinch dynamics G'day from the land of ozzzzzzz
Interesting reading Session CM1 - Mini-conference on Astrophysical Jets I.
Session CM1 - Mini-conference on Astrophysical Jets I.
ORAL session, Monday afternoon, November 15
Room 100/101, SCC Session UO1 - Space and Astrophysical Plasmas, and Gas-Puff Z-pinch Experiments.
Session UO1 - Space and Astrophysical Plasmas, and Gas-Puff Z-pinch Experiments.
ORAL session, Friday morning, October 31
Galisteo/Aztec, ACC
Spinning black holes fire off violent jets
12/08/2004 19:00
NewScientist.com news service
Maggie McKee Spinning black holes fire off violent jets - 12 August 2004 - New Scientist Quote:
Violent jets of matter and energy that shoot out from some black holes originate in their spin, suggest the most realistic simulations of these torrents yet.
Thousands of jets - which radiate at radio wavelengths - have been observed spewing from active galaxies. These galaxies are believed to have black holes at their centres and are called "radio-loud" quasars. The jets are thought to be powered by black holes with masses of a billion Suns. But astronomers cannot agree on how the jets form.
In one leading theory, the jets begin in an accretion disk of ionised gas, or plasma, around the black hole. The plasma's charged particles create magnetic fields as the disk rotates, and those fields push gas and radiation out at the poles of the black hole.
In a competing theory, the jets begin closer to the black hole – and are caused by the wild spinning of the black hole itself. Black holes are so massive that if they rotate, they are thought to drag the surrounding space and time along with them. This blurred region at the edge of the spinning behemoths also twists the magnetic fields generated in the accretion disk as the gas in the disk falls toward a black hole.
It is this confused region of twisting which is believed to spew out the jets.
"The spinning twists up the magnetic field like a barber pole and the plasma is lifted out along the rotational axis," says David Meier, an astrophysicist at NASA's Jet Propulsion Lab in Pasadena, California, who has worked on previous simulations.
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08-05-2008
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#5 (permalink)
| | Understanding |
Re: Plasma Z-Pinch dynamics G'day from the land of ozzzzzzz
We know that in Z-pinch experiments that Neutrons are produce in extra ordinary amounts and also a relutant compaction. Knowing this we can look at the R-process nucleosynthesis.
Interesting paper [0804.0969] Nucleosynthesis in Magnetically Driven Jets from Collapsars
Nucleosynthesis in Magnetically Driven Jets from Collapsars
Authors: Shin-ichiro Fujimoto, Nobuya Nishimura, Masa-aki Hashimoto
(Submitted on 7 Apr 2008) Quote: |
Abstract: We have made detailed calculations of the composition of magnetically driven jets ejected from collapsars, or rapidly rotating massive stars, based on long-term magnetohydrodynamic simulations of their core collapse with various distributions of magnetic field and angular momentum before collapse. We follow the evolution of the abundances of about 4000 nuclides from the collapse phase to the ejection phase and through the jet generation phase using a large nuclear reaction network. We find that the r-process successfully operates only in energetic jets (> 1e51 ergs), such that U and Th are synthesized abundantly, even when the collapsar has a relatively weak magnetic field (1e10 G) and a moderately rotating core before the collapse. The abundance patterns inside the jets are similar to those of the r-elements in the solar system. About 0.01-0.06 Msun neutron-rich, heavy nuclei are ejected from a collapsar with energetic jets. The higher energy jets have larger amounts of Ni56, varying from 0.00037 to 0.06Msun. Less energetic jets, which eject small amounts of Ni56, could induce a gamma-ray burst (GRB) a supernova, such as GRB 060505 or GRB 060614. Considerable amounts of r-elements are likely to be ejected from GRBs with hypernovae, if both the GRB and hypernova are induced by jets that are driven near the black hole.
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10-18-2008
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#6 (permalink)
| | Understanding |
Re: Plasma Z-Pinch dynamics G'day from the land of ozzzzz
This subject should not be treated as an alternative science.
It is science and the amount of experiments in this field makes it the cutting edge science.
Regardless
This is interesting
Simulation of Plasma Jet Dynamics using Hybrid Particle-in-Cell Methods Simulation of Plasma Jet Dynamics using Hybrid Particle-in-Cell Methods
American Physical Society, 48th Annual Meeting of the Division of Plasma Physics, October 30-November 3, 2006, abstract #VP1.125
Oct-06 Quote:
Abstract
High-energy plasma jets have potential applications in both magnetic and inertial fusion^*. Because of the high plasma densities (10^17--10^19 cm-3), and long timescales (several μsec), it is not practical to treat the bulk electrons as kinetic PIC particles. We are applying hybrid methods, including Electron Magnetohydrodynamics (EMHD), where the electrons are treated as an inertialess fluid, and an electron-fluid method, where the electron inertia is retained. The main difficulty in the EMHD method is due to discontinuous field derivatives across the moving plasma-vacuum interface. We solved this by using the vector potential A instead of the E and B fields. We have derived stability conditions for the algorithm: a conventional diffusion-equation constraint, and a constraint on the grid magnetic Reynolds number (ratio of convective to diffusive transport of the magnetic field over one cell). We show results of θ- and z-pinch benchmark calculations in 1D and 2D, and preliminary results applying the algorithm to the HyperV plasma jet experiments.
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and
Production of radiatively cooled hypersonic plasma jets and links to astrophysical jets Production of radiatively cooled hypersonic plasma jets and links to astrophysic
Plasma Physics and Controlled Fusion, Volume 47, Issue 12B, pp. B465-B479 (2005).
Dec-05 Quote:
Abstract
We present results of high energy density laboratory experiments on the production of supersonic radiatively cooled plasma jets with dimensionless parameters (Mach number ~30, cooling parameter ~1 and density contrast ρj/ρa ~ 10) similar to those in young stellar objects jets. The jets are produced using two modifications of wire array Z-pinch driven by 1 MA, 250 ns current pulse of MAGPIE facility at Imperial College, London. In the first set of experiments the produced jets are purely hydrodynamic and are used to study deflection of the jets by the plasma cross-wind, including the structure of internal oblique shocks in the jets. In the second configuration the jets are driven by the pressure of the toroidal magnetic field and this configuration is relevant to the astrophysical models of jet launching mechanisms. Modifications of the experimental configuration allowing the addition of the poloidal magnetic field and angular momentum to the jets are also discussed. We also present three-dimensional resistive magneto-hydrodynamic simulations of the experiments and discuss the scaling of the experiments to the astrophysical systems.
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and
Plasma Jet Studies via the Flow Z-Pinch Plasma Jet Studies via the Flow Z-Pinch
Astrophysics and Space Science, Volume 307, Issue 1-3, pp. 41-45 (Ap&SS Homepage)
Jan-07 Quote:
Abstract
The ZaP sheared-flow Z-pinch produces high density Z-pinch plasmas that are stable for up to 2000 times the classical instability times. The presence of an embedded radial shear in the axial flow is correlated with the observed stability, and is in agreement with numerical predictions of the stability threshold. The case is made that using a higher-Z working gas will produce supersonic plasma jets, consistent with dimensionless similarity constraints of astrophysical jets. This would allow laboratory testing of some regimes of astrophysical jet theory, computations, and observations.
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Could this be the Mechanism that starts the jet from compact cores such as Neutron stars, exotic stars and supercompact cores (black holes). | | |
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