Not So Neutral Neutron

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The neutron may be electrically neutral overall, but physicists had thought it was actually positively charged at its center with an offsetting negative charge at its outer edge. New results from three different particle accelerators suggest the neutron is even more complicated, with a negative charge both in its inner core and in its outer edge and with a positive charge sandwiched in between. The findings could improve understanding of the strong force, which binds atomic nuclei together, as well as the inner workings of stars. It might also have applications in nuclear energy and nuclear weapons. According to researcher Gerald Miller of the University of Washington, the neutron could prove even more complex as more data come in, as he describes in the September 14 Physical Review Letters.

Charles Q. Choi is a frequent contributor to Scientific American. His work has also appeared in The New York Times, Science, Nature, Wired, and LiveScience, among others. In his spare time, he has traveled to all seven continents.

More by Charles Q. Choi
Scientific American Magazine Vol 297 Issue 6This article was published with the title “Not So Neutral Neutron” in Scientific American Magazine Vol. 297 No. 6 (), p. 37
doi:10.1038/scientificamerican1207-37c

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