| 释义 |
neutrino Nuclear Physics.|njuːˈtriːnəʊ|
[a. It. neutrino (E. Fermi 1933, in La Ricerca sci. II. 491), f. neutro neuter a. and n., neutral + -ino, dim. suffix.]
Either of two stable, uncharged leptons (associated respectively with the electron and the muon) which have zero or negligible mass and an extremely low probability of interaction with matter; also, the antiparticle of either of these, one of which is produced (along with an electron and a proton) in the beta decay of a neutron.
1934Sci. Abstr. A. XXXVII. 383 A quantitative theory of the emission of β-rays is explained. This admits the existence of the ‘neutrino’, a new particle proposed by Pauli having no electric charge and mass of the order of magnitude of that of the electron or less. 1938Ann. Reg. 1937 354 The neutrino was generally accepted as a useful working hypothesis, but at least one attempt was made to show that the beta-ray spectrum could be explained without assuming its existence. 1948Sci. News VI. 79 Beta decay is very slow compared to the times taken by other nuclear reactions, and one must, therefore, expect the reverse process, i.e., the capture of a neutrino, also to be very rare. On the Fermi theory, a neutrino could indeed go very many times across the interior of the earth and still have practically no chance of hitting anything. 1956Time 2 July 46/3 For 20 years nuclear physicists have used neutrinos (small, uncharged particles) in their calculations... But no known apparatus has ever detected neutrinos... Last week from the Atomic Energy Commission came big news. Neutrinos do exist. 1958New Scientist 25 Dec. 1567/1 Pauli produced the sorely needed explanation for the variability of the energy of beta-particles thrown out by radioactive materials. He postulated the simultaneous emission of a ghost particle which caried away part of the energy but which had no charge and virtually no mass and so was not observable directly. The neutrino..has been fully vindicated and now occupies a position of great importance in contemporary theory. 1962Physical Rev. Lett. IX. 36/1 The neutrinos we have used produce µ mesons but do not produce electrons, and hence are very likely different from the neutrinos involved in β decay. Ibid. 42/2 The most plausible explanation for the absence of electron showers..is then that νµ ≠ νe; i.e., that there are at least two types of neutrinos. This also resolves the problem raised by the forbiddenness of the µ+ →e+ + γ decay. 1968M. S. Livingstone Particle Physics iv. 74 The muon decays into an electron and two neutrinos: µ- → e- + νe + νµ . 1969Times 20 Feb. 17/5 Neutrinos are emitted as by-products in a great many nuclear reactions. 1974McGraw-Hill Yearbk. Sci. & Technol. 306/1 The neutrino is the only known particle that has only weak interactions. Thus, the neutrino is a unique tool in the study of the weak forces, since the interactions are free of the effects of the strong and the electromagnetic interactions, which are many orders of magnitude stronger. 1974Sci. Amer. Dec. 115/1 At proton accelerators muon neutrinos are produced about 100 times more copiously than electron neutrinos. |