“Microwave horn” particle accelerator

For the design and construction details of ion guns, necessary for more advanced designs and lower vacuums.
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AliAs
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“Microwave horn” particle accelerator

Post by AliAs » Tue Jul 14, 2020 4:29 am

DISCLAIMER: I AM NEW TO FUSION AND THIS FORUM SO PLEASE EXCUSE ME FOR ANY MISTAKES AND TELL ME IN THE COMMENTS

So I was just browsing the forum and found an article regarding using a magnetron for an ion gun. Magnetron reminded of microwave oven parts, and it made me think of microwave horns or guns. They are basically made with the waveguide of a microwave oven which is directed into a horn. Could this be used to accelerate particles, in this case ions, to be an ion gun?

John Futter
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Re: “Microwave horn” particle accelerator

Post by John Futter » Tue Jul 14, 2020 5:10 am

Alias
this sort of question should have been asked in the new user chat area
you seem to have not read all the FAQ's on this site
These are found at the top of each forum section

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Dennis P Brown
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Re: “Microwave horn” particle accelerator

Post by Dennis P Brown » Wed Jul 15, 2020 9:40 am

Also, we require full names.

keelan
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Re: “Microwave horn” particle accelerator

Post by keelan » Thu Oct 08, 2020 2:12 am

The answer to your question is no. That is not how you might build an ion source. Warning: the people here can be a little rough.
"What Mr. Einstein has said is not so stupid"-Wolfgang Pauli

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Dennis P Brown
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Re: “Microwave horn” particle accelerator

Post by Dennis P Brown » Thu Oct 08, 2020 8:59 am

And we repeat things too; like we use full names here including one's full name in the title for posts. Generally, if people offer respect to the forum rules, everyone here is very polite, actually.

As for microwaves and amature applications of microwave drivers - these devices are lethal except by extreme experts.

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Re: “Microwave horn” particle accelerator

Post by Justin Fozzard » Thu Oct 08, 2020 9:14 am

Alias,
You should read the forum rules and FAQ's before posting.
We use our full names here and always try to answer reasonable questions from those that have the courtesy to follow the forum rules.

A microwave horn wouldn't be of any use for an ion gun or accelerator: they are just a method of directing and coupling microwaves to the differing impedances of free space and a transmission line or waveguide.
https://en.wikipedia.org/wiki/Horn_antenna

In order to accelerate ions, you would need to somehow "slow down" the group velocity of the microwaves so that the ions can be coupled to the electric field and be accelerated.
https://www.microwaves101.com/encyclope ... structures

This is possible for electrons as, being much lighter, they move at higher velocities than ions for a given accelerating potential. Electrons are routinely accelerated with microwaves and used to generate intense x-ray sources with iris-loaded microwave cavities as the slow-wave structure.
An equivalent method for ions is a drift-tube, where a much lower frequency RF electric field is applied to the ions as the pass gaps between conducting cylinders along an evacuated tube.
https://www.britannica.com/technology/drift-tube
https://www.coursera.org/lecture/fundam ... -dtl-VzgTq

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Richard Hull
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Re: “Microwave horn” particle accelerator

Post by Richard Hull » Thu Oct 08, 2020 4:31 pm

Great synopsis Justin! The URLs are great.

However, I might imagine "alias" seems to have came and left. Thus, you might be posting to the aether. Still, valuable date for those who are careful enough to use microwaves as an ionizer/ion source. We recommend against it unless one is trained in microwave technology.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

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