Neutron and Negative Proton


ABOUT a year ago, I proposed a method of detecting the decay of the neutron1. Recently, it has been reported that Kapitza has, in the course of the analysis of cosmic ray spectra, discovered the negative proton. Whether this news is true or not, it is quite reasonable to suppose that a free neutron has also the probability of being Î+radioactive*, thus producing a negative proton. This process would, of course, occur only if the mass of the negative proton is smaller than that of the neutron. To detect the existence of this negative proton, one may apply the method similar to that proposed in my previous note1 and then search for the Î+ rays. If the negative proton is the anti-particle of the ordinary proton, the annihilation process might be expected to occur with the emission of one or two photons of energy about 109 eV. These photons will, on encountering the wall of the containing vessel, produce electron showers of a considerable number of particles which may easily be detected by using a counter-controlled cloud chamber arranged in usual ways. These showers can very easily be distinguished from the showers of cosmic rays since we know that the latter are mostly in downward directions.

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    Wang, K. C., Nature, 155, 574 (1945).

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WANG, K. Neutron and Negative Proton. Nature 157, 549 (1946) doi:10.1038/157549b0

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