Chemical equilibrium in QCD gas in the early universe
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 --> ggg represents only a 3% correction to qq --> 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 >~ 3 × 1014 GeV.
- Publication:
-
Physics Letters B
- Pub Date:
- September 1993
- DOI:
- arXiv:
- arXiv:hep-ph/9304273
- Bibcode:
- 1993PhLB..314..298E
- Keywords:
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- High Energy Physics - Phenomenology
- E-Print:
- 10 pages, 4 figures (available upon request), Plain TEX, Nordita 93/32 P