Is it possible to perceive a subatomic particle decay event with the naked eye?

Question

The image above is to help illustrate what I observed, although in this image the line is grey, while what I saw was a bright white line.

This question arises from an experience i had about two years ago, while in my home. I observed a single white line that ended up curling in on itself, and I immediately recognized what it was as i am familiar with illustrations of the same process that occurs in the LHC... The only cause i can think of is that i was in the path of a cosmic ray collision with the earth's atmosphere, which is the only natural source of such particles as they possess very high energies that other radiation sources cant produce, like radioactive materials present in the earth's crust or the sun.

For more detail, what I observed seemed to have no depth in the space around me, meaning that it didn;t occur anywhere in the space in front of me where i had been looking at the time. This leads me to the conclusion that what i saw actually occurred inside my eye. also the orientation of the image allows me to deduce that the particle came from above, because the spiral part was pointing down relative to the straighter part of the line.

Also it was a very short lived event, comparable to watching a lightning strike, giving me barely enough time to even register the image.

Answer 1

PROBABLY, you can visually perceive high-energy charged particles.

On the other hand, it is not likely to see the spiral you explained.

First, in order to get a spiral like in a particle detector you need rather strong magnetic field, maybe survivable, but unlikely to be seen in the wild. Well, at least, not on Earth and outside of a physics lab.

Second, in order to see whatever shape, your eye must be able to focus it - i.e. the shape has to be outside of the eye and even at a certain distance. If the light is created inside and behind the eye's focal system, you will see a light filling your entire visual field or maybe a diffuse spot.

In the unlikely case the particle in question does not induce scintillation in the vitreous body, but directly excites the retina cells, you may see a dot-like or streak-light flash.

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What you have probably seen is some kind of scintillating scotoma - a neurophysiological phenomenon originating in the brain rather than in the eyes. It pretty much fits your explanation.

Answer 2

Two issues, both of which completely rule this out as a particle trajectory.

The spiral path seen in cloud chamber/bubble chamber events like the one below is because of an external magnet. Without a strong external magnet, particle trajectories are just straight lines. An electron (the particle that will curve most), with, lets say $100\,\mathrm{eV}$ of energy in the presence of earth's magnetic field, will have a cyclotron radius (the radius of the circular path) of about $0.3\,\mathrm{m}$, way bigger than your eye. And $100\,\mathrm{eV}$ is probably way too low; the particle needs to have enough energy to produce many photons along its path for a spiral to be visible; each costing a few eV.

Second, if you've ever used a "manual" camera (like a DSLR), you might know that lenses have a certain distance at which they are "focused". You can see things at the focus distance clearly with a sharp edge, and everything else is blurry. This is why it's not so bad to have a piece of dust on your camera lens; it won't do very much to your pictures, because that piece of dust is badly out of focus. If there was some kind of defect inside of your eye, you would not see it; it would be out of focus. It would simply illuminate the entire back of your eye, and you would see a general light across your entire vision. To suggest that you saw something inside your eyeball is equivalent to thinking that when you turn on the light bulb in your room, a perfect image of a light bulb appears on the wall. No; the wall is simply illuminated.

Answer 3

The answer is yes if perceiving by the naked eye means one can see the trace left in a cloud chamber. What you can see is nicely illustrated by this YouTube video. I directly observed less frequent events in a homemade cloud chamber built by a friend of mine.

About the possibility of observing a trace formed "inside the eye" I am more skeptical. Eyes are not cloud chambers. There is no evident mechanism for condensation as an effect of the passage of a charged particle. Moreover, many heterogeneities may be present in the transparent gel inside our eyes, the vitreus body, even with the shape of short spirals.