
Exotic Atom - lelf
https://en.wikipedia.org/wiki/Exotic_atom
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deftnerd
The header of the wikipedia article mentions that because the resulting
particles are usually unstable, the exotic atoms typically have short
lifetimes.

If someone has the time to point to the research, the article would be
massively improved by mentioning the typical lifetimes of each of the listed
exotic atoms.

A "short lifetime" could be nanoseconds or could be years when you compare it
to the traditional lifetime of the non-exotic version of the atom and knowing
what is typical for each exotic atom would be good information to have at a
glance.

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_Microft
The half-life of approximately 15 minutes for free neutrons is considered
_long_. It's actually the longest for any sub-atomic particle if I recall
correctly.

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batbomb
I think protons would like to have a word with you.

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_Microft
Proton decay has never been observed, afaik.

Edit: that's still the case. Since protons can not decay in the standard
model, actually observing it would be huge.

~~~
NZGumboot
_Free protons_ (protons outside of an atom) have never been observed to decay.
Protons inside a nucleus can of course decay, see:
[https://en.wikipedia.org/wiki/Positron_emission](https://en.wikipedia.org/wiki/Positron_emission)

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dschuetz
I don't understand what that Wikipedia entry is supposed to describe. Are
those proposed, or already predicted composite atoms, or have they been
already found?

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cperciva
The article only mentions Muonium in passing -- I guess it's only somewhat
exotic? -- but I can assure you that it's very real. Chemically it acts as a
light isotope of hydrogen, and the interaction of the (anti)muon spin makes it
useful for probing reactions in otherwise problematic environments -- for
example, supercritical water, where the pressure chamber needed for hundreds
of atmospheres of pressure gets in the way of most sensors.

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Olshansky
I legitimately thought this was going to be an "exotic skin" for the atom text
editor.

~~~
oppressedgf
Hey, same! Wasn't disappointed though

