The X-Ray Puzzle of Protostellar Jets

Jun 22, 2011
A false-color image of a portion of the region around the protostar L1551 in the emission light of hydrogen and iron, with various jets and knots marked. X-ray observations suggest that strong magnetic fields in the innermost region around the young star power intense shocks. Credit: Hyashi and Pyo

(PhysOrg.com) -- A new star develops by accreting material from a circumstellar disk; both in turn are embedded in a much larger, more nearly spherical envelope of in-falling dust and gas. The protostar is obscured in the optical by the thick dust in its surroundings, although it can be detected at radio, infrared, and hard X-ray wavelengths which penetrate the material.

The young rotates, and one consequence of its spin is that the star ejects bipolar jets of ionized and molecular gas. These outflows can be readily seen, and are important markers of stellar youth. However the mechanism(s) that drive these protostellar outflows - including the acceleration and the collimation processes - are poorly understood.

The most spectacular manifestations of these outflows are termed Herbig-Haro (HH) objects; they are shocked condensations in the outflows. Sometimes these knots of material are measured to have motions of hundreds of kilometers per second. In ten known cases, are also seen around these HH objects, implying that they have shock velocities over 500 kilometers per second. But this presents a puzzle: to reach such high shock velocities within the jets, models require that the material be ejected with even higher velocities - about 1000 kilometers per second - yet such high velocities have never been detected.

The protostar L1551 is one such case of X-ray emission from a bipolar jet. CfA astronomer Hans Guenther and two colleagues used the Chandra X-ray observatory to study the HH objects associated with L1551. Comparing their new measurements with older ones, they report that the X-ray emission has been constant for over a decade. Their models conclude that mass ejection from the star in the presence of strong magnetic fields around the base of the outflow can maintain a steady shock and produce the X-rays observed. The affected region is only about 10 AU in size (one is the average distance of the Earth from the Sun), small enough that high velocity material would be difficult to spot directly. The results not only help to explain the emission in this protostar, they help resolve the more general puzzle of X-rays from protostars.

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HannesAlfven
2.6 / 5 (5) Jun 22, 2011
Re: "Their models conclude that mass ejection from the star in the presence of strong magnetic fields around the base of the outflow can maintain a steady shock and produce the X-rays observed."

The confusion occurs because theorists have abandoned their fundamentals. What creates the magnetic field to begin with? It originates from an electric current. The x-rays would not be enigmatic within an electrical framework.

Anthony Peratt's Physics of the Plasma Universe explains the process of Marklund Convection:

1. Current flowing in any conductor causes a magnetic field B in concentric circles around the conductor.

2. Current flows from higher potential to lower potential; there is therefore an electric field E aligned with the current. Therefore, a current and its own B field are mutually perpendicular.

(continued ...)
HannesAlfven
2.6 / 5 (5) Jun 22, 2011
3. As a result, the vector cross-product E x B is non-zero, and accelerates both positive and negative charges (ions and electrons) in the same direction. That direction is mutually perpendicular to both E and B. For a cylindrical conductor (or tube), that direction is radial to the axis of the tube, and inwards. Note that the ExB force does not act on neutral particles.

Everything up to this point results from fundamental electromagnetic theory. This is the driving force behind Marklund convection.

4. The scale of the Birkeland current means that the ExB force is large and causes a large radial acceleration of the ions and electrons, which therefore acquire high velocities. The electrons will be accelerated more due to their lower mass; they also apparently tend to spiral around the magnetic field lines rather than maintaining a perfect, radial direction.

(continued ...)
HannesAlfven
3 / 5 (4) Jun 22, 2011
5. As any neutral particles are not affected by the ExB force, there is a high relative velocity between the electrons and the neutral atoms. This is the necessary condition for CIV, which will occur at different velocities for different elements (CIV is a function of the neutral atoms rather than the charged particles).

6. Marklund convection is based on the same inward drift of ions & electrons driven by the ExB force, but also involves a recombination process, whereby elements are radially sorted according to their ionization potentials. H has the highest ionization potential and therefore recombines at the largest radius. So, any H ions (and electrons) drifting in the magnetic field of a flux tube are drawn into the tube radially, and recombine before any other elements. Peratt & Verschuur comment, "A stationary state occurs when the inward coconvection of ions and electrons toward the axis of a filament is matched by recombination and outward diffusion of neutralized plasma."
HannesAlfven
2.6 / 5 (5) Jun 22, 2011
As a result, the neutral atoms may drift outwards from the center of the tube, and yet remain in the vicinity of the tube. This leads to (a) a depletion of H ions in the general area of a flux tube, as well as (b) a concentration of H atoms near the tube, generally arranged along the length of the filament(s). Thus, the ionization potentials will determine where the different species of atoms will be deposited.

7. Putting 5 & 6 together, there is therefore a concentration of H atoms local to a flux tube which are available to be excited by the CIV process caused by the ExB from the tube.

8. Some of the H atoms will be excited at the right level to emit the 21 cm wavelength radiation which radio telescopes tend to be tuned to observe.

9. The Doppler shift associated with this radiation indicates a relative velocity of the H atoms and the galactic disk.

10. We see these concentrations of H atoms in surveys, and astronomers interpret these neutral H filaments as High Velocity Clouds.
HannesAlfven
2.6 / 5 (5) Jun 22, 2011
11. If we analyse the 21cm results, we find that the velocities of the H atoms relative to the galactic disc show up preferentially at three bands of CIV values (50 km/s, 34 km/s and 14 km/s), which represent the universe's most common elements.

12. This is a signature of the CIV effect occurring in the HVC's, which suggests that the HVC's are related to those same filaments.

13. Verschuur and Peratt argue that we are actually looking at twists in the geometry of filaments rather than independent clouds.

Within this alternative view, the Birkeland Currents can transport an incredible amount of energy to very compact objects, thus eliminating the inherent mystery of x-rays within the gravitational framework.
ArkavianX
5 / 5 (2) Jun 22, 2011
Next time just link to the source...it be easier on well you as well..
HannesAlfven
2 / 5 (4) Jun 22, 2011
Re: "Next time just link to the source...it be easier on well you as well.."

It's a textbook.

The point is to explain to the authors of this (and other related) papers the predictions inherent to Marklund Convection. This information is not especially easy to track down on the Internet. Researchers will not find this explanation unless they are looking for it. And without an awareness of the process, they will never understand when predictions are validated. Nor can they compare and contrast different frameworks.

Creative problem-solving demands curiosity and an open-mindedness to fresh ideas -- which in turn demands a familiarity with the basic details of competing ideas. Hannes Alfven made several key important accurate predictions about the universe, and 99% of what we see with our telescopes is matter within the plasma state. It logically follows that theorists should be familiar with the plasma universe framework, so that they can do more than just argue against it.
Deesky
5 / 5 (4) Jun 22, 2011
Re: "Next time just link to the source...it be easier on well you as well.."


It's a textbook.

Yes, a crank's textbook. Why don't you go back to the Thunderbolts forum where you can peddle this nonsense with fellow cranks, hmmm?
Drew_L
1 / 5 (3) Jun 23, 2011
Re: "Next time just link to the source...it be easier on well you as well.."


It's a textbook.

Yes, a crank's textbook. Why don't you go back to the Thunderbolts forum where you can peddle this nonsense with fellow cranks, hmmm?


The thunderbolts.info page has produced more accurate predictions and explanations than any other site ive read. seems like u have no counter argument just negative feed back without any justification. why dont you start by arguing against their theory of the electric sun prediction? im sure youll fall back on reconnecction though rather than proper scientific method. Lets see how much longer thinking like yours lasts.
Deesky
5 / 5 (3) Jun 23, 2011
The thunderbolts.info page has produced more accurate predictions and explanations than any other site ive read

I'd hate to think which sites you read. Why don't you, instead of reading crank sites, try reading some peer reviewed journals.

Or if you can't handle real scientific literature, try this site which is administered by an actual astronomer which debunks EU cosmology with scientific arguments:
http://scientopia...s-wrong/
yyz
5 / 5 (3) Jun 23, 2011
"....if you can't handle real scientific literature, try this site which is administered by an actual astronomer which debunks EU cosmology with scientific arguments:
http://scientopia...s-wrong/"

Hey, thanks for the link, Deesky. I am always looking for good debunking sites wrt EU-PC and Rob's blog is new to me (although I'm familiar with some of his published work).

It can be difficult to find reliable, detailed, quantitative examinations of EU-PC nonsense at a single site, though I find Todd Bridgman's blog (another astronomer) an excellent resource: http://dealingwithcreationisminastronomy.blogspot.com/

Todd's "The Electric Sky, Short-circuited" is a thorough debunking of Donald Scott's "The Electric Sky" (probably one of HA's "textbooks"): http://homepage.m...0322.pdf

HannesAlfven
1 / 5 (3) Jun 23, 2011
From the scientopia site ...

"Here's the thing, though. Even if the "standard" explanation has a flaw, when you introduce an alternate explanation to address that flaw, your alternate explanation must explain everything the standard explanation already explains."

Researchers have learned a lot about the processes of critical thinking and creative problem-solving over the past decade or so. The antiquated approach to evaluating competing ideas in physics has always been to vigorously argue against everything, and observe what survives.

The problem is that nothing survives this approach, guys. Everything can be argued against, and nothing will ever quantitatively compare to a fully-funded framework worked on by many thousands of people.

The philosopher does not try so hard to compare a crab apple to a golden delicious. Neither necessarily needs to "win" if what we are doing is in fact critical thinking and building models for the purpose of a fair comparison.
HannesAlfven
1 / 5 (2) Jun 23, 2011
The real question is this: What approach will succeed in decoding the universe's mechanics? One born of arguing against everything which contradicts conventional theory, and dismissing theories each time that a good argument is found? Or, an approach based upon the elaboration of all models in a manner which is philosophically fair?

I think you will find that, in terms of human psychology, when you instruct students to focus upon one theory, they will memorize it. But, when you teach students two theories, they will compare and contrast them. And we know that this is how critical thinking develops in people.

When people look at one piece of evidence, and try to discount the EU on the basis of that single argument, they ignore the fact that this approach could have similarly discounted the conventional theories at the point of anomalous galactic rotation curves.

So, not only is there no philosophy in that approach, but it also convinces students to avoid critical thinking.
HannesAlfven
1 / 5 (2) Jun 23, 2011
Re: "I'd hate to think which sites you read. Why don't you, instead of reading crank sites, try reading some peer reviewed journals."

It is a common mistake to imagine that peer review provides a reliable system for the creation and elaboration of theories. The problem is that theory creation is an inherently creative process. Peer review provides no mechanisms for stimulating this creative process. And thus, there is an inherent gamble amongst conventional thinkers: They are betting the farm on there not being any mistakes in their models, as they've put no effort into constructing a system for facilitating the creation of ideas which can compete with the conventional theories. People can be forgiven for recognizing that this approach to decoding the universe lacks merit. Nobody should be shamed away from imagining competing models. In fact, if humans are to succeed at this endeavor, without a doubt, there must be places where this creative process is not thwarted.
HannesAlfven
1 / 5 (2) Jun 23, 2011
Jeff Schmidt, a former 19-year editor of Physics Today, wrote a book "Disciplined Minds", which explains in great detail how the physics PhD program weeds out divergent thinking. The system is designed to favor obedient thinkers in the physics graduate program. Divergent thinkers are either expelled or rejected, or simply give up in the midst of the memorization process that is demanded of them.

This process is great for solving problems which can be broken into little pieces -- like building bridges and rocketships (aka abstract thinking). But, on the most difficult questions man has ever asked, and for the purpose of innovating, many authors who study these more difficult problems agree that the proper approach is one of synthesis -- one of bringing together facts and arguments from a wide spectrum of disciplines, and trying to deduce patterns from it all.
HannesAlfven
1 / 5 (2) Jun 23, 2011
The synthesis approach, however, demands an oppeness to fresh ideas, and a curiosity to diverge from an original focus. And this is the ironic part: ideological training in physics actually undermines our attempts at answering the most mind-boggling questions we can ask about the universe. The more you succumb to your inherent psychological desire to avoid uncertainty, the less likely it is that you will ever be part of the solution.

The Electric Universe lacks an ideology. It is an interdisciplinary approach to science which takes nothing for granted. Everything is on the table. There are no sacred assumptions.

We will eventually get to a point where a system is constructed which facilitates the elaboration of this framework. And to the extent that conventional thinkers refuse to participate, students who lack any investment within the conventional ideas will take up the cause, and go on to do that which the conventional thinkers claimed was impossible.
HannesAlfven
1 / 5 (2) Jun 23, 2011
Another interesting irony pertains to the Tokamak. Designed as an attempt to recreate the Sun's power source, it has ironically validated a couple of the EU's claims: that of fractal-like plasma scaling and of filamentary and Faraday motor structures embedded within plasmas of all types.

See "Observations of Skeletal Microstructures in Various Types of Dust Deposit in Tokamak T-10" and "Similarity of Skeletal Structures in Laboratory and Space and the PROBABLE Role of Self-Assembling of a Fractal Dust in Fusion Devices".

The key word there is "PROBABLE", as these guys are deploying artificial intelligence techniques -- aka "probabilistic reasoning" -- to objectively infer the existence of filamentary structures in cosmic plasmas. That's the behavior of an *electrical* plasma.

Their research corroborates Gerrit Verschuur's observation that interstellar plasmas are highly filamentary, and even exhibit critical ionization velocities (an electrical property of plasmas).
HannesAlfven
1 / 5 (2) Jun 23, 2011
So, to the extent that people look to the results of the Tokamak experiments as an attempt to validate the standard solar model, there is no philosophy behind ignoring results which support the competing view -- that dusty plasmas naturally transport electrical energy over Birkeland Currents, and can do so over enormous distances. The algorithms now demonstrate that these structures are "probable" within interstellar space. There is no bias in these algorithms, as there is in human reasoning about theories.

There exists a burden to explain structures like the Cygnus Loop, shown at:

http://www.everyt...ic=356.0

The perfect twisting is virtually impossible to generate with a shock wave model based upon a gravitational framework -- and yet, we know from laboratory plasma physics that electrical plasmas do this naturally due to long-range attraction and short-range repulsion between plasma filaments.
HannesAlfven
1 / 5 (2) Jun 23, 2011
We are not born with an innate ability to be perfectly philosophical in our scientific reasoning. In fact, it is our own psychological tendencies which inspire the need for philosophy of science, to begin with. When we look at an ambiguous photo, it is human nature to infer the more conventional explanation. This is scientific fact, which psychologists no longer wonder about.

And that's just one single example. There are at least 10 or 20 critical psychological tendencies which place human cognition into lines of thought which are not scientifically philosophical.

The truth is that we cannot fully understand the universe until we fully understand ourselves. So, to all those who want to succumb to the innate human desire to avoid uncertainty, and pick a winner in this controversy right now, before the theories are on equal footing, don't forget that you are merely responding to your own human desires, and your approach will ultimately fail, just as those before you did.
TabulaMentis
not rated yet Jun 23, 2011
@HannesAlfven:
Thanks for your long blogs. I could only read a few sentences before getting a headache. In short, you are saying there is a mechanism behind the creation of the following: magnetic lines, galaxy rotation curves and relativistic jets? If yes, then I agree with you!

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