I do not have any education in particle physics, and I am trying to read the paper(adsbygoogle = window.adsbygoogle || []).push({});

http://www.helsinki.fi/~hkurkisu/cosmology/Cosmo6.pdf .

I would much appreciate some help regarding the specific questions below.

The following is from the first page of the article.

I gather thatgis a count of the different varieties of particles of different types. There are some oddities in the table I can't figure out, and I hope someone will be able to explain them to me.

1. Under Quarks,Regards,g= 2⋅2⋅3. I get that one "2" is for the particle and its antiparticle, and the "3"is for 3 colors. What is the other "2"? Is it +1/2 and -1/2 spin values?

2. For each of τ, μ, and e,g= 2⋅2=4, making 12 altogether. One "2" corresponds to the particle and antiparticle. What is the other "2" Is it +1/2 and -1/2 spin values?

3. For Electroweak gauge bosons,g=3. Is this because there are 3 spin values: +1, 0, and -1?

4. Under Electroweak gauge bosons, there is a single line for γ, the photon. Why isg= 2 for the photon?

5. Also, what is the photon mass value in parentheses, "< 6×10^{-17}eV"?

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