Pauli and neutriNO


Wolfgang Pauli was a scientist with "NO" in his mind. Pauli's exclusion principle, that two electrons can't occupy the same quantum state is fundamental for all the chemistry 1) .

In 1930, in order to explain a continous energy distribution of the electrons (and positrons) emitted during
b decays, Pauli suggested the existence of a new particle, so small, that " you have no chance to find it". It was called neutrino by E. Fermi and discovered only in 1956 by C. Cowan and F. Reines.

Neutrinos are detected by reactions opposite to b decay, like 37 Cl->38 Ar. Because the probability of such a reaction is very small with a quite big background, these experiments need big installations placed deep under the Earth surface (on the photo - a boat ride on the surface of the detector lake in Kamioka in Japan).


In 1998 some results of the experiment performed in old Kamioka mine (1000 m below the surface) indicated that, possibly, neutrinos have a non-zero mass.

And recently 2) the mystery of lacking Solar neutrinos has been solved. Is seemed before that Sun produced too little neutrionos - but now it turns up that these were scientists, who were not able to  catch them.


1) In one of his fundamental works Pauli showed that from an assumption on positive values for energy one gets the Fermi-Dirac's statistics for particles with a half spin, and from the assuption on a finite light speed (= information exchange) we gets the Bose-Einstein's statistics for particles with an integer spin. [Phys.Rev. 58 (1940) 716].

2) In 2002,  a flux of electron neutrinos with intensity 1,76x10 6 cm -2 s-1 and a flux of the heavier neutrinos with intensity 3,41x106 cm- 2 s- 1 were observed in Sudbury experiment (=another old mine, in Canada), finally in agreement with Solar nuclear-reactions models.


20 years old Pauli was looking for a job and had to deliver a lecture. The president, a well know professor, commented that Pauli's calculations are not quite clear for him. Pauli answered that physics is difficult and no everyone has to undestand it. Pauli again started looking for a job...
[A.K. Wróblewski, Uczeni w anegdocie].



© GK