From WMAP result (arXiv:1212.5225) we know Baryon/photon ratio η has the value
(6.19 ± 0.14) × 10^(-10).
Now alternatively this can also be defined as Y_{B}=(n_{baryon}-n_{antibaryon})/s, where 's' is entropy density. This Y_{B} is roughly of the order of 10^{-11}. Can anyone tell me the exact value of Y_{B} from recent observation (WMAP , PLANCK data etc.) with reference?
I have not looked in details, but I guess you may find some up-to-date results here:
http://www.physics.utah.edu/snowpac/index.php/snowdark/snowdark-2013-talks-slides
http://arxiv.org/abs/1211.6721v3
The most recent value of baryon to photon ratio is
5.7 x 10-10 < η < 6.7 x 10-10
The reference is R.Y. Cooke, arXiv:1308.3240. The published reference is Astrophys.J. 781 (2014) 31
The analysis is based on precision measurement of primordial helium abundance. Also recent results from CMB anisotropy analysis are taken into account here. This paper is quoted by the Particle Data Group.
- Badges
- Science topic
- Similar topics
- Physical Sciences
- Particle Physics
- Elementary Particle Physics