Astronomy and Astrophysics – Astrophysics
Scientific paper
2004-08-02
Astropart.Phys.23:313-323,2005
Astronomy and Astrophysics
Astrophysics
17 pages, 5 ps figures
Scientific paper
10.1016/j.astropartphys.2005.01.
A recent analysis of the He4 abundance determined from observations of extragalactic HII regions indicates a significantly greater uncertainty for the He4 mass fraction. The derived value is now in line with predictions from big bang nucleosynthesis when the baryon density determined by WMAP is assumed. Based on this new analysis of He4, we derive constraints on a host of particle properties which include: limits on the number of relativistic species at the time of BBN (commonly taken to be the limit on neutrino flavors), limits on the variations of fundamental couplings such as alpha_{em} and G_N, and limits on decaying particles.
Cyburt Richard H.
Fields Brian D.
Olive Keith A.
Skillman Evan
No associations
LandOfFree
New BBN limits on Physics Beyond the Standard Model from He4 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with New BBN limits on Physics Beyond the Standard Model from He4, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and New BBN limits on Physics Beyond the Standard Model from He4 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-306665