<p>I think the question <a href="https://physics.stackexchange.com/questions/193771/are-cosmic-rays-net-neutral-in-charge">here</a> is not answered directly. According to <a href="https://en.wikipedia.org/wiki/Cosmic_ray#Composition" rel="nofollow noreferrer">Wikipedia</a>, </p>

<blockquote>
  <p>Of primary cosmic rays, which originate outside of Earth's atmosphere, about 99% are the nuclei of well-known atoms (stripped of their electron shells), and about 1% are solitary electrons (similar to beta particles). Of the nuclei, about 90% are simple protons (i.e., hydrogen nuclei); 9% are alpha particles, identical to helium nuclei; and 1% are the nuclei of heavier elements, called HZE ions</p>
</blockquote>

<p>Together, electrons and positrons need to be neutral in charge, right? 
Only 1% are electrons. </p>

<p>How can they be neutral in charge?</p>

CC BY-SA 3.0
2017-11-12T02:18:05.433Z
It sounds like they might be giving percentages by mass.  That article also says "A very small fraction are antiparticles".
Phiteros
CC BY-SA 3.0
2017-11-12T02:29:05.470Z
@Phiteros Mproton~1800Melectron Even by mass, if 87% are protons and 12% are Helium nucleus, 87/1800+12/(4*1800)=0.05>>0.01. Special relativity needs to be considered?
questionhang
CC BY-SA 3.0
2017-11-12T02:47:14.580Z
Something does seem amiss.   It's too small a ratio to be explained by mass (Proton mass is 1837 times the Electron's).   But intuitively it's much too large a ratio by charge.   Perhaps Electrons are more easily absorbed flying through space leaving the abundance as protons, or, Electrons carry so much less energy, most of them don't register as cosmic rays.  There might be a minimum energy requirement - which would explain the 99 to 1 ratio and that would be my guess.   But I don't want to make a guess an answer, so I'l leave it here.
userLTK
CC BY-SA 3.0
2017-11-12T15:42:55.523Z
OP is asking about the electron/positron ratio not the electron/proton ratio.
AtmosphericPrisonEscape
CC BY-SA 3.0
2017-11-12T20:20:42.547Z
@AtmosphericPrisonEscape The quote and the first two comments threw me off.  My mistake.
userLTK
CC BY-SA 3.0
2017-11-13T08:45:38.550Z
Related question here:   https://physics.stackexchange.com/questions/63530/what-happens-to-the-electron-companions-of-cosmic-ray-protons
userLTK
CC BY-SA 3.0
2017-11-13T13:55:44.807Z
@userLTK  That question has not been answered.  neutral or not?
questionhang
CC BY-SA 3.0
2017-11-13T15:59:13.317Z
Why would you think various particles have to sum to neutral net charge?  I see no reason for this in anything other than the entire universe.
Carl Witthoft
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2017-11-13T22:45:46.103Z
@questionhang While it's not answered, I felt there was some relevant and interesting information.
userLTK
CC BY-SA 3.0
2017-11-14T01:22:35.323Z
@carl    They are not necessarily neutral.  But it seems nobody talks about it in detail.
questionhang
CC BY-SA 3.0
2017-11-14T01:24:27.507Z
@userLTK agree!
questionhang
<cosmic-ray>
Are electrons and positrons equal in cosmic rays?
questionhang
# Are electrons and positrons equal in cosmic rays?

(Asked by: username_0 on 2017-11-12)

I think the question [here](https://physics.stackexchange.com/questions/193771/are-cosmic-rays-net-neutral-in-charge) is not answered directly. According to [Wikipedia](https://en.wikipedia.org/wiki/Cosmic_ray#Composition),

> Of primary cosmic rays, which originate outside of Earth's atmosphere, about 99% are the nuclei of well-known atoms (stripped of their electron shells), and about 1% are solitary electrons (similar to beta particles). Of the nuclei, about 90% are simple protons (i.e., hydrogen nuclei); 9% are alpha particles, identical to helium nuclei; and 1% are the nuclei of heavier elements, called HZE ions

Together, electrons and positrons need to be neutral in charge, right?
Only 1% are electrons.

How can they be neutral in charge?

**Tags:** cosmic-ray

> **Comments:**
> **username_1**: It sounds like they might be giving percentages by mass.  That article also says "A very small fraction are antiparticles".  
> **username_0**: @username_1 Mproton~1800Melectron Even by mass, if 87% are protons and 12% are Helium nucleus, 87/1800+12/(4*1800)=0.05>>0.01. Special relativity needs to be considered?  
> **username_2**: Something does seem amiss.   It's too small a ratio to be explained by mass (Proton mass is 1837 times the Electron's).   But intuitively it's much too large a ratio by charge.   Perhaps Electrons are more easily absorbed flying through space leaving the abundance as protons, or, Electrons carry so much less energy, most of them don't register as cosmic rays.  There might be a minimum energy requirement - which would explain the 99 to 1 ratio and that would be my guess.   But I don't want to make a guess an answer, so I'l leave it here.  
> **username_3**: OP is asking about the electron/positron ratio not the electron/proton ratio.  
> **username_2**: @username_3 The quote and the first two comments threw me off.  My mistake.  
> **username_2**: Related question here:   https://physics.stackexchange.com/questions/63530/what-happens-to-the-electron-companions-of-cosmic-ray-protons  
> **username_0**: @username_2  That question has not been answered.  neutral or not?  
> **username_4**: Why would you think various particles have to sum to neutral net charge?  I see no reason for this in anything other than the entire universe.  
> **username_2**: @username_0 While it's not answered, I felt there was some relevant and interesting information.  
> **username_0**: @carl    They are not necessarily neutral.  But it seems nobody talks about it in detail.  
> **username_0**: @username_2 agree!  

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## 0 answers

