I What is the new source of space radiation discovered near Earth?

[davenn]

Interesting article ...NEW SOURCE OF SPACE RADIATION: Astronauts are surrounded by danger: hard vacuum, solar flares, cosmic rays. Researchers from UCLA have just added a new item to the list. Earth itself.“A natural particle accelerator only 40,000 miles above Earth’s surface is producing ‘killer electrons’ moving close to the speed of light,” says Terry Liu, a newly-minted PhD who studied the phenomenon as part of his thesis with UCLA Prof. Vassilis Angelopoulos.This means that astronauts leaving Earth for Mars could be peppered by radiation coming at them from behind–from the direction of their own home planet.ASA’s THEMIS spacecraft ran across the particles in 2008 not far from the place where the solar wind slams into Earth’s magnetic field. Researchers have long known that shock waves at that location could accelerate particles to high energies–but not this high. The particles coming out of the Earth-solar wind interface have energies up to 100,000 electron volts, ten times greater than previously expected.How is this possible? Liu found the answer by combining THEMIS data with computer simulations of the sun-Earth interface. When the solar wind meets Earth, it forms a shock wave around Earth’s magnetic field, shaped like the bow waves that form ahead of a boat moving through water. Within this “bow shock” immense stores of energy can be abruptly released akin to the sonic boom of an airplane.Liu found that some electrons are shocked not just once, but twice or more, undergoing mirror-like reflections within the bow shock that build energy to unexpected levels. Most of the boosted particles shoot back into space away from Earth.

Above: Dr. Terry Liu created this diagram showing the location of the natural particle accelerator and how it sprays radiation into space.​

“Similar particles have been detected near Saturn, suggesting that the process is at work there as well,” says Liu. “Indeed,” adds Angelopoulos, “this type of particle acceleration could be happening throughout the cosmos–from supernovas to solar storms–wherever a supersonic wind hits a barrier.”Meanwhile, back home, Earth-orbiting satellites and departing astronauts have a new source of radiation to contend with. It’s right over their shoulder.Read the original research at Science Advances.
Cheers
Dave

 

[mfb]

Please add a link to the article you quoted.

100 keV electrons are easy to shield and astronauts are not in that range for long either. Calling them "killer electrons" is just nonsense.

 

[davenn]

Please add a link to the article you quoted.

The main article is linked at the bottom of the post
it was posted in short form on spaceweather.com. I doubt the main article has the sensationalism that spaceweather is sometimes prone to

 

[mfb]

I don't mean the publication (which is okay), I mean the news article where you copied text from. This article. Which is very sensationalist.

 

[OmCheeto]

Calling them "killer electrons" is just nonsense.

hmmmm...
[google google google]

Are these "killer electrons" different from the "killer electrons" that NASA and the ESA commonly talk about?

Killer Electrons [NASA]​

​

Rise of the Killer Electrons [ESA]​

guessing this is a play on the "Killer Tomatoes" theme.​

I spent about an hour or two this morning looking at the history of theories behind these killer electrons:

Killer Electrons
year culprit
1958 Van Allen
2010/2004 Then Earth’s magnetic lines wobble, creating something like a very large-scale, low frequency laser
2007 gyro-resonant wave–particle interactions
2019 foreshock transient

As usual, I understood very little of any of it.

 

[mfb]

That's a different population of electrons. These belts have electrons with a higher energy.

 

[Klystron]

[snip...]
I spent about an hour or two this morning looking at the history of theories behind these killer electrons:

Killer Electrons
year culprit
1958 Van Allen
[...snip]

The Van Allen "radiation belts" were all the rage in 1950/60's Sci-Fi movies and television shows such as "Voyage to the Bottom of the Sea" -- a popular movie and long-running TV show, predecessor to Star Trek -- where scientists use submarines to escape the deadly radiation.

 

[davenn]

I don't mean the publication (which is okay), I mean the news article where you copied text from. This article. Which is very sensationalist.

which I responded to and lasted less than 6 more hrs before it was removed for the next newsclip

 

[geoelectronics]

"The particles coming out of the Earth-solar wind interface have energies up to 100,000 electron volts, "

What KIND of particles? A 100keV electron is only 0.548c, or about 1/5th the energy as max B- from Strontium-90 decay.

If it was 1 a.m.u. particle @ 100,000 eV = 2729 mi/s.( yawn)

(my calculator)

But wait, add a coil of wire and 40,000 miles of extension cord? Might be able to shut off those coal power plants.

George Dowell

 

[mfb]

Electrons, as discussed in the article.

 

[geoelectronics]

hmmmm...
[google google google]

Are these "killer electrons" different from the "killer electrons" that NASA and the ESA commonly talk about?

Killer Electrons [NASA]​

​

Rise of the Killer Electrons [ESA]​

guessing this is a play on the "Killer Tomatoes" theme.​

I spent about an hour or two this morning looking at the history of theories behind these killer electrons:

Killer Electrons
year culprit
1958 Van Allen
2010/2004 Then Earth’s magnetic lines wobble, creating something like a very large-scale, low frequency laser
2007 gyro-resonant wave–particle interactions
2019 foreshock transient

As usual, I understood very little of any of it.

To help to you understand, Solar Wind is made of mostly electrons and protons, in plasma (NASA) When created at the sun, their speed varies from from 500 to 800 kilometers per second.depending on its origin site (NOAA). Not "near the speed of light" (sensationalist article). Solar Wind arrives at Earth days after a flare.
When it (Solar Wind) hits the influence of Earth's magnetic field, they are deflected, according to their charge ( +/- = opposite directions) and form layers according to their speed (kinetic energy).

Electrons entering a magnetic line of force are deflected, the angle is proportional to their speed (beta spectrograph), their speed (energy) is not affected. Positrons (B+) if present go the opposite direction.

Ask if question, this is also a simple high school physics experiment.

George Dowell

 

[OmCheeto]

To help to you understand, Solar Wind is made of mostly electrons and protons, in plasma (NASA) When created at the sun, their speed varies from from 500 to 800 kilometers per second.depending on its origin site (NOAA). Not "near the speed of light" (sensationalist article). Solar Wind arrives at Earth days after a flare.
When it (Solar Wind) hits the influence of Earth's magnetic field, they are deflected, according to their charge ( +/- = opposite directions) and form layers according to their speed (kinetic energy).

Electrons entering a magnetic line of force are deflected, the angle is proportional to their speed (beta spectrograph), their speed (energy) is not affected. Positrons (B+) if present go the opposite direction.

Ask if question, this is also a simple high school physics experiment.

George Dowell

Umm... If NASA finds the belts puzzling, I'm pretty sure I don't have a chance.

Studying the Van Allen Belts 60 Years After America’s First Spacecraft [NASA]​

Jan. 31, 2018​

Sixty years later, scientists are still working to understand the peculiar and puzzling nature of the Van Allen Belts.​

Btw, NOAA states; "The solar wind continuously flows outward from the Sun..." [ref]

So your statement:

Solar Wind arrives at Earth days after a flare.

strikes me a specious.

 

[geoelectronics]

Umm... If NASA finds the belts puzzling, I'm pretty sure I don't have a chance.

Sixty years later, scientists are still working to understand the peculiar and puzzling nature of the Van Allen Belts.​

Btw, NOAA states; "The solar wind continuously flows outward from the Sun..." [ref]

So your statement:

"Solar Wind arrives days later"

strikes me a specious.

Science has learned a lot about Solar Wind and the Earth's magnetic interaction since James A. Van Allen originally sent a Geiger Counter up in a rocket along with a tape recorder to make a record of the clicking. Explorer 1 launched from Cape Canaveral, Florida, on Jan. 31, 1958 was the first US satellite to carry scientific instruments. I thought it was very cool at the time. The 1950's was a great time to be young and interested in science. 1957-1958 were called the International Geophysical Year and it was really a stimulating time.Solar Wind is continuous and in all directions from the Sun, but there are localized "Solar Storms", "Sun Spots" and "Flares" that cause extra "hot spots" to eject a tremendous burst of matter into a particular like a jet, called Coronal Mass Ejections. When one is aimed directly Earth the earth, it is called a "Halo" and can be very dangerous to satellites, electric power grids and other made made technologies when it arrives.

We watch for those and other events very carefully, one tool is the SOHO satellite (The Solar and Heliospheric Observatory) which exclusively monitors the Sun. Lots of details concerning the subject at NASA's site:
https://www.nasa.gov/mission_pages/soho/index.html
Don't give up on understanding, if you are over 12 years old and have ever held a magnet and a prism, you can understand every principle involved.

George Dowell

PS It is good to be suspicious. Question everything, demand proof,
observe everything closely, experiment.

 

[OmCheeto]

...
you can understand every principle involved.
...

I'm pretty sure I understand the principles involved. I just don't understand how all those principles add up to how the Van Allen Belts exist, at all.

ps. @davenn , I read all the links in your post. I read a dozen more. I'm still not getting it.
I'm guessing it's similar to how a cyclotron works.

This is quite a parameter "busy" problem.

Does anyone have a link to a simulation that follows a single solar wind electron from the sun, to its dance in the belts?

 

[geoelectronics]

I'm pretty sure I understand the principles involved. I just don't understand how all those principles add up to how the Van Allen Belts exist, at all.

ps. @davenn , I read all the links in your post. I read a dozen more. I'm still not getting it.
I'm guessing it's similar to how a cyclotron works.

This is quite a parameter "busy" problem.

Does anyone have a link to a simulation that follows a single solar wind electron from the sun, to its dance in the belts?

Better. Watch this video, in one minute and 20 seconds you will understand perfectly because you can see it with your own eyes.



Ask if questions.

George

 

[OmCheeto]

Better. Watch this video, in one minute and 20 seconds you will understand perfectly because you can see it with your own eyes.



Ask if questions.

George

As I inferred implied moments ago, I've studied electron beam deflection in a cyclotron. Your video doesn't make me understand anything more perfectly, as it's basically the same thing.

 

[geoelectronics]

As I inferred moments ago, I've studied electron beam deflection in a cyclotron. Your video doesn't make me understand anything more perfectly, as it's basically the same thing.

Good. It is exactly the same thing. Energetic electrons generated by some source meet a magnetic field and are deflected. Solar Wind, cyclotron etc. magnets deflect electrons but don't change energy (accelerate).

More energetic electrons are deflected less (in same magnetic field) as less energetic ones- the basis for Beta Particle (electron) energy measurement in a Magnetic Beta Spectrometer. Electrons will deflect one way because of their negative charge, positrons deflect the other way because of their positive charge.

Maybe I'm not address the correct details? It's electrons and magnets.

George Dowell

 

[OmCheeto]

Good. It is exactly the same thing. Energetic electrons generated by some source meet a magnetic field and are deflected. Solar Wind, cyclotron etc. magnets deflect electrons but don't change energy (accelerate).

More energetic electrons are deflected less (in same magnetic field) as less energetic ones- the basis for Beta Particle (electron) energy measurement in a Magnetic Beta Spectrometer. Electrons will deflect one way because of their negative charge, positrons deflect the other way because of their positive charge.

Maybe I'm not address the correct details? It's electrons and magnets.

George Dowell

You shouldn't feel bad, not being able to explain this.
Every site I visited, when the question came up, submitted little more than; "It happens"

 

[geoelectronics]

You shouldn't feel bad, not being able to explain this.
Every site I visited, when the question came up, submitted little more than; "It happens"

No seriously, which part is a problem>? I'm glad to help if we can identify the sticking point. I too hate "it happens" answers! We want real answers, right?

Some things I personally have had to wait for the final answer, for example WHY magnets do what they do. Like you I can OBSERVE what they do and can predict their behavior based upon those observations, but no one has explained the mechanism sufficiently for my true understanding. So I settle for knowing magnetic lines of force exist, demonstrate theirs actions with magnets, motors/generators, electromagnets, wires with currents, compasses etc.

If that's you real question, then I probably can't explain that and like you await someone who can.

Wait, something just occurred to me- electrons THINK they are going in straight lines, free-fall, just as an orbital satellite for example, and simply doesn't notice it's being acted on by an outside force (Gravity, static electric, magnetism) Could this be the clue?

George Dowell

 

[davenn]

To help to you understand, Solar Wind is made of mostly electrons and protons, in plasma (NASA) When created at the sun, their speed varies from from 500 to 800 kilometers per second.depending on its origin site (NOAA). Not "near the speed of light" (sensationalist article). Solar Wind arrives at Earth days after a flare.
When it (Solar Wind) hits the influence of Earth's magnetic field, they are deflected, according to their charge ( +/- = opposite directions) and form layers according to their speed (kinetic energy).

Don't know if this is your thoughts or if you were quoting an unknown source ?
Some things in it are not overly accurate eg

the 500 to 800 is way off and very limiting
300 to 1100 km/sec is a much more accurate range 300 - 400 km/sec is pretty normal for a quiet sun
And blasts of up to 1000 - 1200 km/sec for some of the major solar flares and assoc. CME's

Coronal holes generate bursts of solar wind speeds up to ~ 500 - 600 km/sec

Solar Wind arrives at Earth days after a flare.

This was also poorly worded hence why Om questioned it

So your statement:

Solar Wind arrives at Earth days after a flare

strikes me a specious.

Om is correct ...

George, you should have said CME, not Solar Winsd as the Solar Wind is continuously flowing
from the sun.

electrons THINK they are going in straight lines

Electronics DONT think anything, they don't have minds

When one is aimed directly Earth the earth, it is called a "Halo"

no, that is not the definition of a halo, more properly full halo, CME. A full halo CME relates
to its shape and size ... It's irrelevant to if there is an "earth" or any other planet in orbit around the sun

Electrons entering a magnetic line of force are deflected...

... into a spiral path around those magnetic field lines

a whole lot of images here ...
https://www.bing.com/images/search?q=electrons+entering+the+earth's+magnetic+field&FORM=HDRSC2Dave

 

[OCR]

As I inferred moments ago. . .

I guess you could have. . . inferred moments ago ?

But you probably meant. . . implied moments ago ?
hmmmm... ?
[google google google]

.

 

[OmCheeto]

I guess you could have. . . inferred moments ago ?

But you probably meant. . . implied moments ago ?

hmmmm... ?
[google google google]
.

believe it or not:

Om's browser history:

Jul 30, 2019 imply vs. infer : Choose Your Words : Vocabulary.com​

Jul 30, 2019 inferred vs implied - Google Search / www.google.com​

ps. fixed!

 

[OCR]

ps. fixed!

✔[/size]

.

 

[geoelectronics]

Don't know if this is your thoughts or if you were quoting an unknown source ?
Some things in it are not overly accurate eg

the 500 to 800 is way off and very limiting
300 to 1100 km/sec is a much more accurate range 300 - 400 km/sec is pretty normal for a quiet sun
And blasts of up to 1000 - 1200 km/sec for some of the major solar flares and assoc. CME's

Coronal holes generate bursts of solar wind speeds up to ~ 500 - 600 km/sec

This was also poorly worded hence why Om questioned it
Om is correct ...

George, you should have said CME, not Solar Winsd as the Solar Wind is continuously flowing
from the sun.

Electronics DONT think anything, they don't have minds

"no, that is not the definition of a halo, more properly full halo, CME. A full halo CME relates
to its shape and size ... It's irrelevant to if there is an "earth" or any other planet in orbit around the sun"

Encyclopedia Britannica: CMEs that are launched toward Earth are called halo CMEs because as they approach Earth, they appear larger than the Sun, making a “halo” of bright coronal emission completely around it.
To this I add, if it weren't pointed at earth, it wouldn't look like a HALO. George Dowell
... into a spiral path around those magnetic field lines

a whole lot of images here ...
https://www.bing.com/images/search?q=electrons+entering+the+earth's+magnetic+field&FORM=HDRSC2Dave

Sure Dave, one at a time. Happy to- In Quotes are your questions or comments:

Dave: "Don't know if this is your thoughts or if you were quoting an unknown source ?
Some things in it are not overly accurate eg

the 500 to 800 is way off and very limiting
300 to 1100 km/sec is a much more accurate range 300 - 400 km/sec is pretty normal for a quiet sun
And blasts of up to 1000 - 1200 km/sec for some of the major solar flares and assoc. CME's

Coronal holes generate bursts of solar wind speeds up to ~ 500 - 600 km/sec"

Answer= NASA Docs :
The Solar Wind

The solar wind streams off of the Sun in all directions at speeds of about 400 km/s (about 1 million miles per hour). The source of the solar wind is the Sun's hot corona. The temperature of the corona is so high that the Sun's gravity cannot hold on to it. Although we understand why this happens we do not understand the details about how and where the coronal gases are accelerated to these high velocities. This question is related to the question of coronal heating.
DialPlot.jpg (12900 bytes)

Click on image for larger version.

Solar Wind Variations

The solar wind is not uniform. Although it is always directed away from the Sun, it changes speed and carries with it magnetic clouds, interacting regions where high speed wind catches up with slow speed wind, and composition variations. The solar wind speed is high (800 km/s) over coronal holes and low (300 km/s) over streamers. These high and low speed streams interact with each other and alternately pass by the Earth as the Sun rotates. These wind speed variations buffet the Earth's magnetic field and can produce storms in the Earth's magnetosphere.

The Ulysses spacecraft completed two orbits through the solar system during which it passed over the Sun's south and north poles. Its measurements of the solar wind speed, magnetic field strength and direction, and composition have provided us with a new view of the solar wind. Ulysses was retired on June 30, 2009.

The Advanced Composition Explorer (ACE) satellite was launched in August of 1997 and placed into an orbit about the L1 point between the Earth and the Sun. The L1 point is one of several points in space where the gravitational attraction of the Sun and Earth are equal and opposite. This particular point is located about 1.5 million km (1 million miles) from the Earth in the direction of the Sun. ACE has a number of instruments that monitor the solar wind and the spacecraft team provides real-time information on solar wind conditions at the spacecraft . NASA

next: "George, you should have said CME, not Solar Winsd as the Solar Wind is continuously flowing
from the sun."

Yes it is, but when we're talking about a single electron (as was asked) if the wind and that one electron leaves the sun now, it won't arrive today. The wind arriving today left long before. These are physical particles not rays. George Dowell

Next: "Electronics DONT think anything, they don't have minds "
I often tell students to take on the persona of a photon or particle and describe what they feel, how they behave etc. It gives them a frame of reference and scale. And this is science class, I never never correct a student's English errors. As a matter of fact my first statement is "PERFECT ENGLISH IS NOT REQUIRED HERE" Obviously many of those seeking advice do not have English as their first language. George Dowell

"
geoelectronics said:
Electrons entering a magnetic line of force are deflected...

... into a spiral path around those magnetic field lines

a whole lot of images here ..."

What's the question. I work with electrons and positrons and can demonstrate anything you want to see in this regard.

Now please, let's start from the basics-someone in authority define "RAYS". Simple question, simple answer

George Dowell

 

[davenn]

Solar Wind Variations

The solar wind is not uniform. Although it is always directed away from the Sun, it changes speed and carries with it magnetic clouds, interacting regions where high speed wind catches up with slow speed wind, and composition variations. The solar wind speed is high (800 km/s) over coronal holes and low (300 km/s) over streamers. These high and low speed streams interact with each other and alternately pass by the Earth as the Sun rotates. These wind speed variations buffet the Earth's magnetic field and can produce storms in the Earth's magnetosphere.

nothing in there that I didn't already state above or already know.
It agrees with what I said, not with what you said

Yes it is, but when we're talking about a single electron (as was asked) if the wind and that one electron leaves the sun now, it won't arrive today.

We weren't talking about single electrons ... of course it wont, nothing new there

I often tell students to take on the persona of a photon or particle and describe what they feel, how they behave etc. It gives them a frame of reference and scale.

well you shouldn't as it gives a false idea to them and this is what leads to future confusion

These are physical particles not rays.

Of course they are particles not rays, I, nor anyone else said they were rays
don't add to the confusion

. And this is science class, I never never correct a student's English errors. As a matter of fact my first statement is "PERFECT ENGLISH IS NOT REQUIRED HERE" Obviously many of those seeking advice do not have English as their first language.

yes, it is science and therefore you should stick to science

perfect English may not be necessary BUT accurate science is and sadly that isn't what you are teaching

What's the question. I work with electrons and positrons and can demonstrate anything you want to see in this regard.

You made a statement that was far from complete. I showed you the info for clarity
It appeared you didn't /don't know what is really happening to electrons / protons when they interact with the Earth's magnetic field ??

Now please, let's start from the basics-someone in authority define "RAYS". Simple question, simple answer

DONT go there... it is totally irrelevant to this thread

And finally a request that everyone here would appreciate

Please learn to quote It helps with reading clarityDave

 

[geoelectronics]

"It appeared you didn't /don't know what is really happening to electrons / protons when they interact with the Earth's magnetic field ??"

Maybe I don't. Please inform me of the truth. I'm willing to learn.
Thank you
George Dowell

 

[Klystron]

[...snip...]
Please learn to quote It helps with reading clarity

As per the Op's request. For @geoelectronics

Hi George,
We are on version 5 of the Forum software. I am still learning features myself.
Quotes can be added to a post many ways.

From the toolbar above a reply box, pull down '...' and 'Insert' 'Quote' then paste or type between the quote boxes to get a different background that members recognize.

If you want to quote an entire post, click the 'Reply' icon at bottom right. The original post appears with software codes that identifiy the member, thread, and post number. Useful and quick. Forum rules allow us the edit the quote for brevity. I sometimes use the old edit notation [snip] just as a courtesy. Or we can highlight text in a post and then click on '+Quote' or 'Reply'. The latter works just like 'Reply' but on the selected string, as I did above. Notice @davenn 's smiley face came also. By prefixing an "@" sign to Dave's member name, it becomes a hyperlink and notifies him.

'+Quote' on selected text or '+Quote' icon at bottom right of a post adds the selected text or entire post, respectively, to your quote buffer. In the reply box click on 'Insert Quote' to examine your collected quotes and select what you want to use. Multi-quote buffer follows you and allows us to gather texts each with member identification.

I still need to learn how to quote external sources like wikipedia using the blue background box. I have been using 'Insert URL' from the chain 'link' icon on the upper toolbar.

--Norm

 

[geoelectronics]

As per the Op's request. For @geoelectronics

Hi George,
We are on version 5 of the Forum software. I am still learning features myself.
Quotes can be added to a post many ways.

From the toolbar above a reply box, pull down '...' and 'Insert' 'Quote' then paste or type between the quote boxes to get a different background that members recognize.

If you want to quote an entire post, click the 'Reply' icon at bottom right. The original post appears with software codes that identifiy the member, thread, and post number. Useful and quick. Forum rules allow us the edit the quote for brevity. I sometimes use the old edit notation [snip] just as a courtesy. Or we can highlight text in a post and then click on '+Quote' or 'Reply'. The latter works just like 'Reply' but on the selected string, as I did above. Notice @davenn 's smiley face came also. By prefixing an "@" sign to Dave's member name, it becomes a hyperlink and notifies him.

'+Quote' on selected text or '+Quote' icon at bottom right of a post adds the selected text or entire post, respectively, to your quote buffer. In the reply box click on 'Insert Quote' to examine your collected quotes and select what you want to use. Multi-quote buffer follows you and allows us to gather texts each with member identification.

I still need to learn how to quote external sources like wikipedia using the blue background box. I have been using 'Insert URL' from the chain 'link' icon on the upper toolbar.

--Norm

 

[geoelectronics]

Thanks Klystron, I'll look this up later.

George Dowell

 

[Klystron]

"Lighten up, Geo.", as the photon said to the electron.

This OP operates a seismology station in the Southern hemisphere IIRC. Very cool posts. PF has members around the globe. Look at some old threads when you have the time for some interesting perspective. The ground (knowledge) moves under our feet.

I taught basic electronics and radar science 40 years back. The knowledge level on the engineering forums staggers me. I love Math but have to query wikipedia to make sure I have the correct category (abstract joke) on some threads. Snowbirds know when to chill and absorb sunlight, right?

--Norm

 

[geoelectronics]

As I inferred implied moments ago, I've studied electron beam deflection in a cyclotron. Your video doesn't make me understand anything more perfectly, as it's basically the same thing.

In the above post, the OP said:
"As I inferred implied moments ago, I've studied electron beam deflection in a cyclotron. Your video doesn't make me understand anything more perfectly, as it's basically the same thing. "

Dear OP.
If you've studied cyclotron theory, you know that electrons (let's call them charged particles in this discussion), are deflected into an almost circular path by a stationary perpendicular magnetic field. For a given magnetic field the circular path will hold them in different "orbits" depending on their kinetic energy (speed):

If nothing is done to alter their kinetic energy, they keep going around in those orbits forever. You've heard of CRT displays, magnetic bottles magnetic lenses and e-e+ storage rings?
Charged particles change their speed (energy state) up and down by external interactions, which are many. If free space, perfect vacuum, they find little reason to change states (Newton's First Law):
In a cyclotron, energy is added by alternating the electrical charge on the Dees, accelerating the charged particles into a widening spiral- by the time they have reached the exit port, their energy is of the magnitude required for the experiment or industrial project:

Charged particles, magnet = Solar Wind, earth.
Here the layers are formed one again by the magnetic field, separated by their speed, into different orbits.

Perhaps better than a cyclotron, the action of a mass spectrometer is a more appropriate example because here we have a charged particle (ion) at a predetermined speed, interaction with a fixed magnet of appropriate flux, but in this case, assuming the charged particles are the same speed, they are separated my their mass.

Speaking directly to the electrons and charged particles in orbit around the earth, they occupy orbital altitude base on their speed.

If their speed changes, they will occupy a higher or lower orbit (“layer”) accordingly.

Check out the “First Cosmic Velocity”

Thank goodness for our strong magnetic field, without it, the world would be very different.

Geo

 

[berkeman]

If nothing is done to alter their kinetic energy, they keep going around in those orbits forever.

Is that true? It's true for a straight path, but for a curved path, something happens to steal energy from the charged particle, no?

 

[OmCheeto]

Is that true? It's true for a straight path, but for a curved path, something happens to steal energy from the charged particle, no?

Cyclotron radiation?
As I said, I've studied up on cyclotrons. It doesn't mean I fully understand how they work.
I'm guessing they leave out a lot of minor details.
For instance, why don't the particles seem to be affected by gravity? Are cyclotrons designed to minimize the effect? Likewise, a lack of knowledge of cyclotron radiation might lead someone to claim that the particles inside a cyclotron would stay in orbit forever.

Viewpoint: Cyclotron Radiation from One Electron
...
Electric charges radiate when moving in circular orbits in a magnetic field, an effect that was first predicted by Oliver Heaviside in 1904. Cyclotron radiation has been observed in astrophysical radio sources and is the basis for generating x rays at synchrotrons.
...

Btw, I'm getting a sense of how these "space accelerators" work. But some of the details are unfortunately left up to my imagination, which is quite dangerous.

Perhaps I should go back and review the wiki entry;

Van Allen Radiation Belt: Causes​

It is generally understood that the inner and outer Van Allen belts result from different processes. ​

Never mind. This is what we pay scientists for isn't it? To get rid of the "generally"? Sounds like mansplaining.

 

[berkeman]

Btw, I'm getting a sense of how these "space accelerators" work. But some of the details are unfortunately left up to my imagination, which is quite dangerous.

 

[Vanadium 50]

If you've studied cyclotron theory, you know that electrons (let's call them charged particles in this discussion), are deflected into an almost circular path by a stationary perpendicular magnetic field. For a given magnetic field the circular path will hold them in different "orbits" depending on their kinetic energy (speed):

If nothing is done to alter their kinetic energy, they keep going around in those orbits forever.

Except that it doesn't. Cyclotrons have only weak focusing. A circular orbit has no restoring force perpendicular to the plane, so you need to either a) continually accelerate and extract before the beam hits the floor or the ceiling, or b) put the beam on a potato-chip shaped orbit so that there is some focusing in the perpendicular direction.

You picked a bad example.

 

[geoelectronics]

Is that true? It's true for a straight path, but for a curved path, something happens to steal energy from the charged particle, no?

I hope I'm using "quote" correctly, if not please give guidance...

Are you asking if the curved path intrinsically reduces energy vs. a straight path?

Otherwise, yes even photons can alter an electron's energy state markedly, it doesn't have to be another particle of matter.

Geo

 

[berkeman]

Are you asking if the curved path intrinsically reduces energy vs. a straight path?

Yep! Through what mechanism? (and yes, this is a test...)

 

[geoelectronics]

Yep! Through what mechanism? (and yes, this is a test...)

Induction.
a.k.a. electromagnetic induction.

Geo

 

[geoelectronics]

Yep! Through what mechanism? (and yes, this is a test...)

Is the static magnetic field at right angles to the motion of the electron, or some other angle?
Right angle presents a circular e- path, other angles present a spiral, as shown in the video.

Geo

 

[mfb]

Induction.
a.k.a. electromagnetic induction.

Geo

No.
Synchrotron radiation (aka cyclotron radiation, same concept). This has been mentioned before already. Charged particles flying through a magnetic field not aligned with their flight direction emit some of their energy as radiation.

For instance, why don't the particles seem to be affected by gravity? Are cyclotrons designed to minimize the effect?

Gravity is negligible compared to all the other forces the particles experience. If you want to store particles for a relevant time span you need focusing magnets (or, rarely, electric fields) anyway.

 

[geoelectronics]

No.
Synchrotron radiation (aka cyclotron radiation, same concept). This has been mentioned before already. Charged particles flying through a magnetic field not aligned with their flight direction emit some of their energy as radiation.
Gravity is negligible compared to all the other forces the particles experience. If you want to store particles for a relevant time span you need focusing magnets (or, rarely, electric fields) anyway.

You didn't specify relativistic speeds. We were talking about Solar Wind (~ 1 million miles per hour). Not near the speed of light. Is this forum only for quantum physics, or is classical everyday physics allowed?
Perhaps I misunderstood. Geo

 

[mfb]

You didn't specify relativistic speeds.

The whole thread is about electrons at relativistic speeds. Not that it would matter, at lower speeds it is called cyclotron radiation but it is fundamentally the same concept: Charges being deflected by a magnetic field radiate.

We were talking about Solar Wind (~ 1 million miles per hour).

The protons are slow but this thread is about the electrons.

Is this forum only for quantum physics, or is classical everyday physics allowed?

I don't see how this question would be related to the thread. Physics used should be suitable for the topic discussed. If quantum mechanics is relevant then a classical description will fail.

 

[geoelectronics]

The whole thread is about electrons at relativistic speeds. Not that it would matter, at lower speeds it is called cyclotron radiation but it is fundamentally the same concept: Charges being deflected by a magnetic field radiate.The protons are slow but this thread is about the electrons.I don't see how this question would be related to the thread. Physics used should be suitable for the topic discussed. If quantum mechanics is relevant then a classical description will fail.

Please refer back to response #26.

ooops...My error. You are correct, I read the article at the beginning just now. It does say relativistic. My response was to the OP question and was only trying to help him.
Quantum Physics it is. Not my thing. I get it finally, I can't talk quantum and you won't classical physics.

George Dowell
73 DE K0FF

 

[berkeman]

73 DE K0FF

You know that accelerating electrons produces EM radiation (even if not relativistic electrons), or else our antennas would not work...

 

[OmCheeto]

I wish I'd known of the following image before I subscribed to this thread:

[ref]

What a bloody menagerie.
I was contemplating doing the maths, following an electron's path, after it hit the magnetopause, but...
Nope. I'm pretty sure I'd pop one too many blood vessels on my way to the end.

It is fun to think about though.
I find it hard to grasp the magnetopause current.
Aren't the solar wind particles moving REALLY fast?
Isn't the magnetic strength there REALLY weak?

I really do need to do some calculations.

ps. This is a pretty cool image of the magnetopause currents:

[ref]

 

[swampwiz]

Interesting article ...NEW SOURCE OF SPACE RADIATION: Astronauts are surrounded by danger: hard vacuum, solar flares, cosmic rays. Researchers from UCLA have just added a new item to the list. Earth itself.“A natural particle accelerator only 40,000 miles above Earth’s surface is producing ‘killer electrons’ moving close to the speed of light,” says Terry Liu, a newly-minted PhD who studied the phenomenon as part of his thesis with UCLA Prof. Vassilis Angelopoulos.This means that astronauts leaving Earth for Mars could be peppered by radiation coming at them from behind–from the direction of their own home planet.ASA’s THEMIS spacecraft ran across the particles in 2008 not far from the place where the solar wind slams into Earth’s magnetic field. Researchers have long known that shock waves at that location could accelerate particles to high energies–but not this high. The particles coming out of the Earth-solar wind interface have energies up to 100,000 electron volts, ten times greater than previously expected.How is this possible? Liu found the answer by combining THEMIS data with computer simulations of the sun-Earth interface. When the solar wind meets Earth, it forms a shock wave around Earth’s magnetic field, shaped like the bow waves that form ahead of a boat moving through water. Within this “bow shock” immense stores of energy can be abruptly released akin to the sonic boom of an airplane.Liu found that some electrons are shocked not just once, but twice or more, undergoing mirror-like reflections within the bow shock that build energy to unexpected levels. Most of the boosted particles shoot back into space away from Earth.

View attachment 247941

Above: Dr. Terry Liu created this diagram showing the location of the natural particle accelerator and how it sprays radiation into space.​

“Similar particles have been detected near Saturn, suggesting that the process is at work there as well,” says Liu. “Indeed,” adds Angelopoulos, “this type of particle acceleration could be happening throughout the cosmos–from supernovas to solar storms–wherever a supersonic wind hits a barrier.”Meanwhile, back home, Earth-orbiting satellites and departing astronauts have a new source of radiation to contend with. It’s right over their shoulder.Read the original research at Science Advances.
Cheers
Dave

Pardon my dumb question but didn't the Lunar missions go to an altitude of 240K miles?

 

[sophiecentaur]

PS It is good to be suspicious. Question everything, demand proof,
observe everything closely, experiment.

That could sound a bit of a Motherhood and Apple Pie thing (gotta be good) but, in practice, proofs of modern Scientific advances are probably far too hard for your average reader (me too) to appreciate and experiments often cost thousands or millions of quid to carry out. When you get down to it, we have to accept the authority of peer reviewed papers and credible magazines (sometimes PF is a good start).