Robert Mann - An Introduction to Particle Physics and the Standard Model · Problem 15.5

Testing the Quark Model — Robert Mann

Physics — Particle Physics · glueball-g-parity

Problem

A glueball is a color-singlet bound state of two gluons, something expected from QCD. The simplest glueball state

|\mathfrak{G}\rangle

has positive parity, zero angular momentum, and is even under charge conjugation. (a) What is the

\mathbb{G}

-parity of this glueball? (b) What is its strangeness? (c) Which of the following reactions are allowed ((a))

\mathfrak{G} \to \pi^+ + \pi^-

((b))

\mathfrak{G} \to \pi^0 + \pi^0

((c))

\mathfrak{G} \to \pi^0 + \pi^0 + \pi^0

assuming that the glueball is sufficiently massive so that energy conservation is satisfied for each?