Finding Range of Weak Interaction from Mass of Z Boson

div4200
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Homework Statement



One of the mediators of the weak interactions is the Z boson, which has a mass of 91 GeV/c
2.

Use this information to find an approximate value for the range of the weak interaction.

Homework Equations



This is the part that I am having trouble with. I don't know where to look for information about this, and it doesn't seem to be in my book. All I ask is that someone point me to a resource where I can read about that topic. I would appreciate it greatly. Thanks in advance!

The Attempt at a Solution



(see above)
 
One way to approach the problem is just by dimensional analysis. What length scale corresponds to the mass? A better way, which gives essentially the same answer is to determine the corresponding Yukawa potential http://en.wikipedia.org/wiki/Yukawa_potential for Z-boson exchange.
 
Thanks. But I'm still somewhat confused. How can mass and length be related using dimensional analysis?

I also read the article about Yukawa potential, but I'm not sure how to use it. I would think that you would set V = 0 , but that yields the solution r = ∞, which cannot be right.

Thanks.
 
I just thought of something. What if I do,

E = mc2 = hc/[tex]\lambda[/tex]

And so:

[tex]\lambda[/tex] = h/(mc)

Plugging in the following values:

h = 4.13566733 * 10-15 eV*s
c = 2.99792458 * 108 m/s
m = 9.1 * 109 eV/c2

I get

[tex]\lambda[/tex] [tex]\approx[/tex] 1.4 * 10-16 m

Is that correct? Thanks a lot.
 
div4200 said:
Thanks. But I'm still somewhat confused. How can mass and length be related using dimensional analysis?

Any mass is related to an energy by multiplying by [tex]c^2[/tex]. Any energy is inversely related to a length by a factor of [tex]\hbar c[/tex]. For instance, the relation between energy and wavelength of a photon is

[tex]\lambda = \frac{\hbar c}{E}.[/tex]

I also read the article about Yukawa potential, but I'm not sure how to use it. I would think that you would set V = 0 , but that yields the solution r = ∞, which cannot be right.

Thanks.

You would be better off asking a question like: over what distance does the potential decrease by half? Be sure to avoid choosing [tex]r=0[/tex] or [tex]r=\infty[/tex] as reference points.
 
Ah I think I see now. So my method was correct, then?

And isn't your h-bar actually supposed to be h since E = hv?
 
Last edited:

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