Fusor Forums

Hello to all,

For those who need to size electrostatic lenses, the following paper can, possibly, be of some interest for them:
http://f6cte.free.fr/Electrostatic_lens ... _Rev_A.pdf

Patrick Lindecker

Hello to all,

I fixed several bugs of the rev. A version. So here is the Rev. B version:
http://f6cte.free.fr/Electrostatic_lens ... _Rev_B.pdf

Patrick Lindecker

Hi Patrick
Thanks for sharing.
Not useful for my project but a friend of mine, in struggle with an electrostatic accelerator will enjoy your info.

Nice Roberto if this paper can help a bit.

Patrick

Hello to all,

I updated this paper in version C1: http://f6cte.free.fr/Electrostatic_lens ... _Rev_C.pdf
It can be added that the §5.4.2 and the Appendix E of:
http://f6cte.free.fr/Proposal_of_a_prog ... Rev_A1.pdf develop a bit the case "Fusion plasma".

Here is the abstract:
The goal of this presentation is to give some information about the sizing of electrostatic lenses (mainly the focal length), used to focus particles beams. It is proposed a small program and formulas, taking account different parameters (voltages and configuration) in a relative simple way.
This presentation relies on a personal simulator.
A physical explanation of the focusing principle is proposed. It is afterwards explained why a negative potential will also focus a ions beam, even it seems counter-intuitive.
Moreover, it is given the expected behavior of lenses in presence of a strong space charge, or in presence of two different types of plasma (hot ions/cold electrons plasma and fusion neutral plasma).

Patrick Lindecker

I hope this gets flag to be included in the FAQ's! This is a very useful resource for not just a deuterium ion accelerator in general but for any 'gun' application.

Hello to all,

I updated this paper in version C2: http://f6cte.free.fr/Electrostatic_lens ... _Rev_C.pdf

The revision C2:
* introduces some information about the thickness of a lens in relation with the quality of convergence (made in §3.3 and in Appendix A),
* and proposes, for information, the Multiplasma version 1.19 program limited to electrostatic lenses, to download in “freeware”, from this direct link: http://f6cte.free.fr/MULTIPLASMA_V_1_19 ... _setup.exe
Note 1: this program is to be used as it is, as there is no online help. But, possibly, questions can be asked on this thread.
Note 2: first read the “Quick start-up of the Multiplasma V.1.19 program in its limited version for electrostatic lenses” document in the “Multiplasma_for_lenses_start_up.pdf” file, before using this program.

Here is the abstract:
The goal of this presentation is to give some information about the sizing of electrostatic lenses, mainly the focal length. These lenses are used to focus particles beams. It is proposed a small program and formulas taking account different parameters (voltages and configuration) in a relative simple way. A “freeware” program can, possibly, help the reader to more precisely design lenses.
This presentation relies on a personal simulator. A physical explanation of the focusing principle is proposed. It is afterwards explained why a negative potential will also focus an ions beam, even it seems counter-intuitive. It is also shown that the quality of convergence increases with the thickness of the lens.
Moreover, it is described the expected behavior of lenses in presence of a strong space charge, or in presence of two different types of plasma (hot ions/cold electrons plasma and fusion neutral plasma).

Thanks to Dennis and Richard for the inclusion of this thread in the FAQ's.

Patrick Lindecker

Could you please just upload the paper to the site, and link to the uploaded paper.

You can add attachments to your post, and .pdf files are allowed.

You might also just upload the program as well, so that all of the information and data is actually part of fusor.net, and won't disappear if the site where you have stuff stored now goes down.

Plus the site you are pointing at does NOT support https, which makes most modern browsers unhappy about visiting the site and downloading any data. Fusor.net doesn't have that problem.

Also, most external links on fusor.net go bad eventually. Sites just go away, or they move, and then the links are dead and the information is effectively gone.

Thanks.

Joe.

Hello Joe,

As I have yet "published" this paper on Zenodo (Electrostatic_lens_sizing_Rev_C2.pdf), I have just added the program related to this paper (i.e. MULTIPLASMA_V_1_19_lenses_setup.exe). So both (paper+program) can be downloaded from Zenodo at https://zenodo.org/record/8434161.

The complete Zenodo reference is:
LINDECKER Patrick. (2023). Electrostatic lens sizing (Version C2). Zenodo. https://doi.org/10.5281/zenodo.8434161


Patrick