What is it about?

Using sets of permanent magnets and blades, we built a device that is able to extract particles with a specific velocity from a beam of magnetic particles.

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Why is it important?

Neutral particle beams with a narrow velocity distribution are required in many experiments, in which fundamental laws of chemical reactions are studied. Our velocity filter does not contain any electronics or quickly moving mechanical parts so it is very reliable.


I hope that the technical solution described here finds its application in diverse experimental set-ups because it is fairly simple. I have done a lot of work to describe the trajectories of particles using simple mathematical formulas so I believe that the results are easily reproducible. Honestly, I do not believe that the device described here will find any practical usage outside of our scientific niche but the article may inspire others to use arrays of magnets in the similar way for completely different purposes.

Michal Hejduk
University of Oxford

Read the Original

This page is a summary of: Manipulating hydrogen atoms using permanent magnets: Characterisation of a velocity-filtering guide, Review of Scientific Instruments, March 2019, American Institute of Physics, DOI: 10.1063/1.5078573.
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