Pions being the lightest mesons play a key role in explaining the properties of the strong nuclear forces in their lower energy range.

DAPHNE was built to observe charged light mesons from the decay of excited nucleon states.

Since the D meson is the lightest meson containing a charm quark, it must change the charm quark into another quark to decay.

Pions are the lightest mesons (and, more generally, the lightest hadrons), because they are composed of the lightest quarks (the u and d quarks).

Mesons are not considered to be gauge bosons of the strong force, because only the lighter mesons are thought to be responsible for the interaction responsible for the strong force.

It is called a B-factory for its copious production of B-mesons which provide a golden mode to study and measure the CP violation due to its property of decaying into other lighter mesons.

The 1 multiplet of light mesons may show similar behavior to that of the vector mesons, in that the mixing of light quarks with strange quarks appears to be small for this quantum number.

In nature, the importance of lighter mesons is that they are the associated quantum-field particles that transmit the nuclear force, in the same way that photons are the particles that transmit the electromagnetic force.

The nuclear force occurs by the exchange of virtual light mesons, such as the virtual pions, as well as two types of virtual mesons with spin (vector mesons), the rho mesons and the omega mesons.

Jefferson Lab conducts a broad program of research using the electromagnetic interaction to probe the structure of the nucleon (protons and neutrons), the production and decay of light mesons, and aspects of the interactions of nucleons in the atomic nucleus.

Despite this fall from grace, the Vector Meson Dominance model still sometimes makes significantly more accurate predictions of hadronic decays of excited light mesons involving photons than subsequent models such as the relativistic quark model for the meson wave function and the covariant oscillator quark model.