Realistic solar corona loops simulated in lab

Caltech applied physicists have experimentally simulated the sun's magnetic fields to create a realistic coronal loop in a lab.

Coronal loops are arches of plasma that erupt from the surface of the sun following along lines. Because plasma is an ionized gas—that is, a gas of free-flowing electrons and ions—it is an excellent conductor of electricity. As such, solar corona loops are guided and shaped by the sun's magnetic field.

The earth's magnetic field acts as a shield that protects humans from the strong X-rays and energized particles emitted by the eruptions, but communications satellites orbit outside this shield field and therefore remain vulnerable. In March 1989, a particularly large flare unleashed a blast of charged particles that temporarily knocked out one of the National Oceanic and Atmospheric Administration's geostationary operational environmental satellites that monitor the earth's weather; caused a sensor problem on the space shuttle Discovery; and tripped circuit breakers on Hydro-Québec's power grid, which caused a major blackout in the province of Quebec, Canada, for nine hours.

"This potential for causing havoc—which only increases the more humanity relies on satellites for communications, weather forecasting, and keeping track of resources—makes understanding how these solar events work critically important," says Paul Bellan, professor of applied physics in the Division of Engineering and Applied Science.

Although simulated have been created in labs before, this latest attempt incorporated a magnetic strapping field that binds the loop to the sun's surface. Think of a strapping field like the metal hoops on the outside of a wooden barrel. While the slats of the barrel are continually under pressure pushing outward, the metal hoops sit perpendicularly to the slats and hold the barrel together.

The strength of this strapping field diminishes with distance from the sun. This means that when close to the solar surface, the loops are clamped down tightly by the strapping field but then can break loose and blast away if they rise to a certain altitude where the strapping field is weaker. These eruptions are known as and (CMEs).

CMEs are rope-like discharges of hot plasma that accelerate away from the sun's surface at speeds of more than a million miles per hour. These eruptions are capable of releasing energy equivalent to 1 billion megatons of TNT, making them potentially the most powerful explosions in the solar system. (CMEs are not to be confused with solar flares, which often occur as part of the same event. Solar flares are bursts of light and energy, while CMEs are blasts of particles embedded in a magnetic field.)

The simulated loops and strapping fields provide new insight into how energy is stored in the solar corona and then released suddenly. Bellan worked with Caltech graduate student Bao Ha (MS '10, PhD '16) to create the strapping field and coronal loop. The results of their experiments were published in the journal Geophysical Research Letters on September 17, 2016.

Bellan and his colleagues have been working on laboratory-scale simulations of phenomena for two decades. In the lab, the team generates ropes of plasma in a 1.5-meter-long .

"Studying coronal mass ejections is challenging, since humans do not know how and when the sun will erupt. But laboratory experiments permit the control of eruption parameters and enable the systematic explorations of eruption dynamics," says Ha, lead author of the GRL paper. "While experiments with the same eruption parameters are easily reproducible, the loop dynamics vary depending on the configuration of the strapping magnetic field."

Simulating a strapping field with strength that fades over the relatively short length of the vacuum chamber proved difficult, Bellan says. In order to make it work, Ha and Bellan had to engineer electromagnetic coils that produce the strapping field inside the chamber itself.

After more than three years of design, fabrication, and testing, Bellan and Ha were able to create a strapping field that peaks in strength about 10 centimeters away from where the plasma loop forms, then dies off a short distance farther down the vacuum chamber.

The arrangement allows Bellan and Ha to watch the plasma loop slowly grow in size, then reach a critical point and fire off to the far end of the chamber.

Next, Bellan plans to measure the magnetic field inside the erupting loop and also study the waves that are emitted when plasmas break apart.


Explore further

Image: Majestic solar eruption larger than Earth

More information: Bao N. Ha et al. Laboratory demonstration of slow rise to fast acceleration of arched magnetic flux ropes, Geophysical Research Letters (2016). DOI: 10.1002/2016GL069744
Journal information: Geophysical Research Letters

Citation: Realistic solar corona loops simulated in lab (2016, November 7) retrieved 13 October 2019 from https://phys.org/news/2016-11-realistic-solar-corona-loops-simulated.html
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Nov 07, 2016
Oh, look, physicists that are plasma experimentalists. I was led to believe by certain members of this forum that this never happened.

Nov 07, 2016
Oh look, applied physicists that actually do experiments unlike their theoretical astrophysicist counterparts who prefer their fanciful thought experiments. There are many plasma experimentalists and they have done yeoman's work for years, astrophysicists choose to ignore their research because they can't get the plasma to comply to the MHD modeling they rely upon.

Nov 07, 2016
astrophysicists choose to ignore their research because they can't get the plasma to comply to the MHD modeling
@cantREADTROLL
really? lets examine that one
from the study
This behavior is in agreement with the predictions of the torus instability
wow, so where did they get that from?
Kliem and Torok, 2006; Olmedo and Zhang, 2010
and how did they model the torus instability?
Bateman, B. 1978, MHD Instabilites, MIT, Cambridge, MA
http://spd.stanfo...medo.pdf

FR-based ideal magnetohydrodynamics (MHD) models, involving catastrophic loss-of-equilibrium (Forbes & Isenberg 1991; Isenberg et al. 1993)
https://arxiv.org...7532.pdf

and all that simply be *reading* the study linked above

conclusion: this experiment was done by initially modeling the plasma in MHD and then replicating it (again, using MHD) in a lab, which then reinforces the MHD models

learn to read more than cult propaganda

Nov 07, 2016
@cantreadTROLL cont'd
astrophysicists choose to ignore their research
more to the point, this also demonstrates the blatant lie behind your continued assurances that astrophysicists ignore plasma research
why?
starting with the article
Although simulated coronal loops have been created in labs before
hmm, i wonder where you could find this info?
oh, right! the studies and lab links i've left you for years!
from Cal-tech to PPPL to others

you know, those labs that validate (or falsify) science?

while you are at it, note how many astrophysics journals are references in the above study

so the problem isn't the scientists or the astrophysicists, nor is it MHD

the problem is that you regurgitate your cult's religious propaganda as fact while not being able to read well enough

this should help
http://www.readingbear.org/

Nov 07, 2016
@full of bsch*tt
BTW how precisely is the sun producing this strapping field? Clarifying that might prevent this from being a joke
well, there isn't anything stopping you from creating a series of experiments that can be validated and then publishing them in a peer reviewed journal demonstrating your knowledge of plasma physics to the world

of course, it would also require you to adhere to the scientific method
- and not just voice your opinion on why science somehow doesn't meet or support your belief system

i await your link showing all of us the validated study you publish

thanks

Nov 07, 2016
@full of bsch*tt
Once again, your brain cell cannot differentiate between observation and opinion
i am not the one making a claim about the observations of a lab experiment and calling it false

so technically, you are the one with the "brain cell [that] cannot differentiate between observation and opinion" so "you really need to get that thing checked out" yourself
you can answer how the "strapping" field is generated at the suns surface
so, because you don't want to believe the physical evidence that is demonstrated (not opinion)
you will attempt to argue that it isn't fact?

what i really want to know is: how do you *know* the "strapping field" isn't generated at the suns surface?

you made the claim, so where is the evidence that it isn't?

more to the point: what are the so called missing variables in the rest of the coronal loop?

and who said the sun is a solid surface?

feel free to link the studies supporting your claims like i did

Nov 07, 2016
@full of schitt
it never existed until it was required for this experiment
I see...
so, ignoring the 1964 patent with references, i found more than 2000 links in google scholar, of which the following directly refute your claim
http://iopscience...736/meta

http://iopscience.../52/meta

http://iopscience...025/meta

http://physics.gm...2010.pdf

so, i guess reading and comprehension isn't your strong point either

but that is only searching specifically for the references of "strap fields" in "MHD", mind you

i will stop there and give you the chance to retract your statement and reconsider your position (not that it has ever done any good) - but also because i am leaving for dinner

nice to see that you don't change, though... simply argue that it can't be true because you don't understand it

nice try

Nov 07, 2016
Bshott, "strapping" fields are created by Birkeland currents. It is the electric current flowing which causes the self fields to squeeze the flow into the tube like Birkeland currents.

http://www.ptep-o...1-13.PDF

Nov 07, 2016
@full of bschitt
I read the description of the lab experiment and said it wasn't even close to simulating a coronal loop
i have to comment on this too...

you made a claim about "strapping field" and it's existence and you suggest, per your wording, that you are not only well versed in physics, but that you also know at least as much as the typical astrophysicists...
and yet, a cursory search of "strapping field" lead me to more than 2K results, with at least 180 individual studies from google scholar alone

so we can see that you're either ignorant of facts or so completely incompetent that you make blatantly false claims that are proven as false by a cursory search, as i just demonstrated

considering this, why, then, should anyone actually listen to your input with regard to physics?

you just proved that you can't do basic research & you don't know sh*t about plasma physics - even cd knows about "strapping fields"

and she only reads pseudoscience!

Nov 08, 2016

Simply stated, no it's not. There is no "force free" field aligned current, unless you have, as been requested more times here than should have been necessary, done it experimentally. Plasma without a magnetic field = glowing haze. Show us the plasma self aligning to create a magnetic field...or just keep claiming it happens until you die. (that will come first BTW)

First, you apparently do not understand what "force free" means. It would seem that you share a level of ignorance regarding plasma physics which is barely surpassed by astrophysicists.
Secondly, Birkeland currents have been reproducedealing in labs since the time of, we'll Birkeland over 100 years ago.
Cee, where is this plasma w/o a magnetic field? Are you suggesting there are no magnetic fields on the Sun? Why are you bringing it up? BTW, there is a current flowing through our glowing plasma...

Nov 08, 2016
@full of bschitt
I said no strapping field "OBSERVED"
no, you specifically said
this is the first mention of a strapping field, it never existed until it was required for this experiment
and i just proved that you are blatantly lying about that
with evidence

so what did you do when i give you evidence proving you wrong?
Lets pull some key phrases...links
so what you're saying is, you got caught in a blatant lie and now you want to backpedal and make fun of the wording in studies you don't understand that completely demolish your argument about the existence of the "strapping field"???

then claim you said something else?

uh huh... reading comprehension fail?
try http://www.readingbear.org/

...you haven't a clue as to how to discern between evidence and claims when it comes to physics, and you are apparently proud to show everyone
you are the one who just got caught blatantly lying about the existence of strapping fields, silly troll-girl

Nov 08, 2016
@full of bschitt cont'd
before you get all stupid about your claims and what you think you said, remember that it is still in black and white above
more to the point, i actually quoted you when i linked the studies
it never existed until it was required for this experiment
so when you realised your screwup and backpedal with
Hey... I said no strapping field "OBSERVED"
this makes me smile because it points out what i've been saying about you for years: you don't know WTF your talking about

i leave you with your own words, which are relevant to you especially

This is why you talking about "evidence" (or even science at all) always cracks me up, you haven't a clue as to how to discern between evidence and claims when it comes to physics (science), and you are apparently proud to show everyone.

& i can prove you can't differentiate between evidence and claims with your own words
http://phys.org/n...ant.html

Nov 08, 2016
@full of bschitt - last important point

you're attempting to distract from the point with your argument of:
Lets pull some key phrases
considering that the point wasn't the content, but that the strapping field existed while you claimed it was made up

so (again/still) you continue to make a lot of claims, but have no references or material to substantiate your claims (just your derision for mainstream science)

considering i just proved your claims to be flat wrong and blatantly false, then anyone with even no knowledge of STEM would have to question how reliable your other claims are, especially as you're not able to link or state references or produce evidence to substantiate them

IOW - you've built a strawman argument to attempt a redirection because you've been proven to be either:
1- a blatant liar
2- completely incompetent
3- stupid
4- trolling
5- all of the above

its proven fact above, in your own words
that isn't a matter of debate
its fact

Nov 09, 2016
sigh... @illiterate and full of bschitt
The point is, in the above comment I clearly state that we have not mapped a "strapping field" in any of the suns magnetic field measurements
you sure about that?
you checked google scholar?
i just checked (again) and (again) found you to be a liar - http://www.nature...omms8008

https://arxiv.org...4437.pdf

hence my argument above about your broken google
but lets talk about why you're confused... perhaps it because you don't know WTF you're talking about
what is a strapping field?
the kink and torus instabilities, determined by the core field of magnetic flux rope and overlaying field (named strapping field)
IOW - it's an overlaying field

so you wanna try that again and post where we've never observed an overlaying field in our observations of the sun?

go ahead... i will simply pull up yet another study that proves you're incapable of actually reading what is written

take your time

Nov 09, 2016
@illiterate and full of bs cont'd
This is why putting one in an experiment and then claiming it is there
yeah, because you think it was never observed
if only there was a way to check your statement against the facts
oh wait! ....

so... why didn't you do that before commenting?

i your own words back at ya:

Once again you have proven you cannot combine reading, and comprehension together...ever. Everything you post after showing you simply cannot understand English is a joke...just like you and whatever it is you think you are accomplishing by engaging me

and once again I have used it to demonstrate that you, quite simply, are nothing more than mindless buffoon

You are pathetic, delusional and really don't belong at a site discussing science whatsoever

Good move. Your [sic] a mental midget who is simply not up to the task of discussing physics

No [sic] go and find a cause more suited to your level of intelligence
(perhaps pretending to be a rock)

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