Pairs of these particles are emitted in the major pathway for iron-45 decay. The delta-plus-plus particle commonly decays to a positive pion and one of these particles. Quantum tunneling by these particles is the dominant process in the (*) Grotthuss mechanism at low temperatures. The "spin crisis" exists because these particles' spin is not accounted for by the spin of their constituent quarks. These particles are the main constituents of cosmic rays. One down quark and two up quarks compose - 
Pairs of these particles are emitted in the major pathway for iron-45 decay. The delta-plus-plus particle commonly decays to a positive pion and one of these particles. Quantum tunneling by these particles is the dominant process in the (*) Grotthuss mechanism at low temperatures. The "spin crisis" exists because these particles' spin is not accounted for by the spin of their constituent quarks. These particles are the main constituents of cosmic rays. One down quark and two up quarks compose - for 10 points - what particles found with neutrons in atomic nuclei?
Pairs of these particles are emitted in the major pathway for iron-45 decay.
protons