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arXiv · hep-ph/9304273

Chemical equilibrium in QCD gas in the early universe

Kari Enqvist·Jukka Sirkka
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Abstract

We compute the thermally averaged $\qq$--annihilation rate into two and three gluons in the early universe. We show that at very high temperatures $\qq\to ggg$ represents only a 3\%\ correction to $\qq\to gg$. Comparing the annihilation rate to the Hubble rate, corrected for particle interactions in the Standard Model gas, we find that quarks and gluons are not in chemical equilibrium when $T\gsim 3\times 10^{14}$ GeV.

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Kari Enqvist, Jukka Sirkka. 1993-04-20. Chemical equilibrium in QCD gas in the early universe. https://doi.org/10.1016/0370-2693(93)91239-j

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