Hadron. In particle physics, a hadron i/ˈhædrɒn/ (Greek: ἁδρός, hadrós, "stout, thick") is a composite particle made of quarks held together by the strong force (in a similar way as molecules are held together by the electromagnetic force).
Of the hadrons, protons are stable, and neutrons bound within atomic nuclei are stable, whereas other hadrons are unstable under ordinary conditions; free neutrons decay with a half life of about 880 seconds. Experimentally, hadron physics is studied by colliding protons or nuclei of heavy elements such as lead, and detecting the debris in the produced particle showers. List of particles. This is a list of the different types of particles found or believed to exist in the whole of the universe.
For individual lists of the different particles, see the individual pages given below. Elementary particles[edit] Fermions[edit] Fermions are one of the two fundamental classes of particles, the other being bosons. Fermion particles are described by Fermi–Dirac statistics and have quantum numbers described by the Pauli exclusion principle.