منابع مشابه
Neutrinos and Primordial Nucleosynthesis
The importance of the Big Bang Nucleosynthesis (BBN) as a unique tool for studying neutrino properties is discussed, and the recent steps towards a self-consistent and robust handling of the weak reaction decoupling from the thermal bath as well as of the neutrino reheating following the e − e− annihilation are summarized. We also emphasize the important role of the Cosmic Microwave Background ...
متن کاملNeutrinos from primordial black holes.
The emission of particles from black holes created in the early Universe has detectable astrophysical consequences. The most stringent bound on their abundance has been obtained from the absence of a detectable diffuse flux of 100 MeV photons. Further scrutiny of these bounds is of interest as they, for instance, rule out primordial black holes as a dark matter candidate. We here point out that...
متن کاملDirac neutrinos and primordial magnetic fields
We consider random primordial magnetic fields and discuss their dissipation, coherence length L0, scaling behaviour and constraints implied by the primoridal nucleosynthesis. Such magnetic fields could excite the right-helicity states of Dirac neutrinos, with adverse consequences for nucleosynthesis. We present solutions to the spin kinetic equation of a Dirac neutrino traversing a random magne...
متن کاملUnstable massive tau-neutrinos and primordial nucleosynthesis
The impact of unstable Majorana ντ on primordial nucleosynthesis is considered. The mass and lifetime of ντ are taken in the intervals 0.1-20 MeV and 0.001-400 sec respectively. The studied decay modes are ντ → νμ + φ and ντ → νe + φ, where φ is a massless (or light) scalar. Integro-differential kinetic equations are solved numerically without any simplifying assumptions. Our results deviate ra...
متن کاملStandard and non-standard primordial neutrinos
The standard cosmological model predicts the existence of a cosmic neutrino background (CνB) with a present density of about nν + nν̄ ≃ 110 cm per flavour, which affects big-bang nucleosynthesis (BBN), cosmic microwave background (CMB) anisotropies, and the evolution of large scale structures (LSS). We report on a precision calculation of the CνB properties including the modification introduced ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Annual Review of Nuclear and Particle Science
سال: 2006
ISSN: 0163-8998,1545-4134
DOI: 10.1146/annurev.nucl.56.080805.140548