A cosmic question mark (just an artifact)

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https://www.legacysurvey.org/viewer/ra=208.3681&dec=1.0206&layer=decals-dr5

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I am intrigued by a lot of these artefact shapes. Cosmic rays are hideously weird and a lot of the time these “death spirals” of cosmic ray-seeming artefacts don’t seem to stack up with what they should be like. Are all shapes like this cosmic rays? I feel like a fair few of them could be pixel misfire cascades or overheating or something. very weird

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I think shape really depends on energy. A high energy muon would probably be more straight, but a low energy electron may cause something like this.

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I had something interesting to say and it’s completely slipped my mind. Something about the nature of cosmic rays that was very interesting. I will remember it by tomorrow hopefully. I cant understand why the squiggly path takes the shape it does sometimes (maybe less energetic ones have instabilities and asymmetries in their decay nature that leads to them spiralling due i.e. imbalance of charge position). No clue but will think about that and the thought I thought I had

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50% of it came back to me in that these aren’t technically cosmic rays but the bits of air showers but the point I had was not one of semantics. Time for a deep dive into literature and maths I don’t understand - I will return with the point I had about something not adding up.

I was recently at my local science center (not the one in this video) and saw a cloud chamber and it was truly mesmerizing watching the cosmic ray trails – recommend!

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WOW! I had no idea…. Thanks

These are very cool to watch to be honest.

On the artefact above, I have finally somewhat collected my thoughts and written them out in the doc attached here. It has a brief overview of detector tech and what is actually happening with cosmic rays and artefacts.

In relation to the original post, my point was that it is not likely the path of a cosmic ray. The reasons why are explained more clearly in the document but basically the magnetic field required to curl a cosmic ray that much (and at almost 90 degree angles at times) would be immense. Couple other reasons as well to do with detecting cosmic rays.

Hope it is interesting :slight_smile:

P.S. on the subject of cool things I have found what I think might be the world’s coolest integral and solution

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Yes maybe but I don’t think you could get any of them to turn the large angles shown there. Would need one big magnetic field

There’s a good article on different kinds of cosmic rays / artifacts in CCDs. The CCDs in DECam are 250 microns, so “thick” by this paper’s definition.

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I only went to a cloud chamber once at a space museum in Ohio… but if you been to the aftermentioned museum, it was really fun!

Wow, nice!

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DOH! :smirk:
I should have read the abstract from the paper in Dustin’s post before posting

D I S R E G A R D
T H E
R E S T
O F
T H I S
P O S T

In the Exploritorium video the narrator says something like “it’s not just cosmic rays / muons that you see - there are also electrons, positrons, alpha particles… but you know you’ve seen a cosmic ray when the line is long and straight”

I’m left wondering if ‘cosmic ray’ is a catch-all in the CCD realm as well.

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Yes, very much so from what I have gathered. There is a very good book that does brilliantly in explaining cosmic rays and everything - I would highly recommend it (although the going gets a bit tougher towards the end).

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