An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

فرهنگ ریشه شناختی اخترشناسی-اخترفیزیک

M. Heydari-Malayeri    -    Paris Observatory

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Number of Results: 1 Search : cosmic neutrino background (CNB)
cosmic neutrino background (CNB)
  نوترینو‌ی ِ پس‌زمینه‌ی ِ کیهانی   
notrino-ye paszamine-ye keyhâni

Fr.: fond cosmologique de neutrinos   

The theoretical → low-energy neutrinos that decoupled from the rest of matter about two seconds after the → Big Bang when the temperature dropped to approximately 2.5 MeV (redshift of z ~ 6 ×109). The CNB is similar to the → cosmic microwave background (CMB), but older. It is estimated that today the CNB has a temperature of Tν = (4/11)1/3Tγ, ~ 1.95 K (or 1.67 × 10-4 eV), where Tγ is the CMB temperature of 2.728 K. Also called the relic neutrinos.

cosmic; → neutrino; → background.