The best replacement for neutrons is protons.

The best alternatives to neutrons are rated as following:
★★★★★  protons
★★  electrons
★  protons heavier
★  x rays
  fast neutrons

Your alternative for neutrons is not listed? Suggest!
Speaking about neutrons, one probably shouldn't forget about atomic number.

Other search terms related to neutrons and their ratings are:
★★★★★ atomic number
★★★★ nucleus
★★★ atomic mass
★★★ mass number
You have in mind a companion for neutrons and it is not yet here? Propose!



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neutrons
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