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The Postulate of the Neutrino

There seemed to be no acceplable escape from this dilemma; apparently Iinear momentum and angular momentum (and energy) were not conserved in the elementary process of p decay. However, the conservation principles were (and are) so much a part of the thinking concerning physical processes that there was a great reluctapce to forgo these enormously successful and useful laws.    ^

In order to solve the problem, Wolfgang Pauli, in 1930, postulated the existence of a new elementary particie that we now cali the neutrino. If Pauli’s neutrino is indeed emitted along with the electron in P decay, the neutrino could carry off the missing Iinear momentum, angular momentum, and energy. But to do all of this and to account for the fact that it had thus far escaped detection, the neutrino had to be endowed with unlikely properties - it must carry no charge and have no mass, it must have almost no interaction with ordinary matter, but it must carry off Iinear momentum, angular momentum, and energy while travelling with the velocity of light! However, in 1953 Clyde Cowan and Fredrick Reines conducted a remarkable series of experiments in which the neutrino was actually detected.

EXERCISES

Match the words with their synonyms.
1) property	a) hint, indication
2) postulate	b) intangible
3) clue	c) only, exclusively
4) solely	d) lost, lacking
5) regarding	e) ąuality
6) missing	f) concerning
7) elusive	g) assumption

2. Match the words from the text with their Polish equivalents.

1) magnitude	a) rozpad
2) decay	b) obdarzać
3) thus	c) ładunek elektryczny
4) endow	d) pęd
5) charge	e) wielkość, rozmiary
6) postulate	f) w ten sposób
7) momentum	g) założenie

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