Fig5_3 solar neutrino fluxes

Fig5_3  solar neutrino fluxes

Fig. 5.3 . Calculated and measured solar neutrino fluxes have consistently disagreed for several decades. The fluxes are measured in solar neutrino units, abbreviated SNU, which is defined as one neutrino interaction per trillion trillion trillion, or 1036, atoms per second. Measurements from the chlorine neutrino detector (small dots) give an average solar neutrino flux of 2.6 ? 0.2 SNU (lower broken line), well below theoretical calculations (large dots) that predict a flux of 8.5 ? 1.8 SNU (upper broken line) for the Standard Solar Model. Other experiments have also observed a deficit of solar neutrinos, suggesting that either some process prevents neutrinos from being detected or there is an incomplete understanding of the nuclear processes that make the Sun shine.

Copyright 2010, Professor Kenneth R. Lang, Tufts University