The solar neutrino unit (SNU) is a unit of Solar neutrino flux widely used in neutrino astronomy and radiochemical neutrino experiments. It is equal to the neutrino flux producing 10−36 captures per target atom per second.[1] It is convenient given the very low event rates in radiochemical experiments. Typical rate is expected to be from tens SNU to hundred SNU.[2]

There are two ways of detecting solar neutrinos: radiochemical and real time experiments. The principle of radiochemical experiments is the reaction of the form

.

The daughter nucleus's decay is used in the detection. Production rate of the daughter nucleus is given by , where

  • is the solar neutrino flux
  • is the cross section for the radiochemical reaction
  • is the number of target atoms.

With typical neutrino flux of 1010 cm−2 s−1 and a typical interaction cross section of about 10−45 cm2, about 1030 target atoms are required to produce one event per day. Taking into account that 1 mole is equal to 6.022×1023 atoms, this number corresponds to ktons of the target substances, whereas present neutrino detectors operate at much lower quantities of those.

See also

Links

References

  1. ^ http://permalink.lanl.gov/object/tr?what=info:lanl-repo/lareport/LA-UR-97-2534-12 1997
  2. ^ "The Solar FAQ: Solar Neutrinos and Other Solar Oddities".
source: http://en.wikipedia.org/wiki/Solar_neutrino_unit