psi3770
psi(3770), designated ψ(3770), is a charmonium resonance, a bound state of a charm quark and its antiquark, with quantum numbers J^PC = 1^−−. It lies just above the open-charm threshold, at a mass near 3.773 GeV, and is the lowest-lying charmonium state above D meson pair production. Its total width is about 27 MeV, which is relatively narrow for a resonance above threshold.
Because its mass exceeds the threshold for D D̄ production, ψ(3770) decays predominantly into a pair of
Most of the ψ(3770) is interpreted as the 1^3D1 charmonium state, with some possible mixing with the
ψ(3770) is produced in electron–positron annihilation, notably at e+e− colliders operated near 3.77 GeV, such as
Together with other charmonium states, ψ(3770) contributes to the charmonium spectrum that helps map quark–antiquark bound