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The empirical identification of bound states of gluons has remained a centralgoal of hadron spectroscopy. We suggest an experimentally challenging, butmodel--independent way to assess which zero charge, isospin-zero mesons have alarge gluonium light-front wavefunction component in the quark and gluon Fockspace of QCD. Our method exploits QCD counting rules which relate the power-lawfall-off of production amplitudes at high momentum transfer to the meson'stwist (dimension minus spin of its minimum interpolating operators). Scalar$0^+$ glueballs composed of two valence gluons with zero internal orbitalangular momentum have twist $\tau=2$. In contrast, quark-antiquark $|q \bar q\rangle $ scalar mesons have twist $\tau \ge 3$ since they have nonzero orbitalangular momentum, and multi-quark states such as $|q q \bar q \bar q \rangle$tetraquarks yield twist $\tau \ge 4$. Thus, the production cross section forboth $|q\bar{q}\rangle$ and $|qq\bar{q}\bar{q}\rangle$ mesons will besuppressed by at least one power of momentum transfer relative to glueballproduction. For example, in single inclusive particle hadroproduction $ A B \toC X$, the cross section for glueball production at high transverse momentum$p_T$ and fixed $x_T = 2 {p_T\over \sqrt s} $ will dominate higher twist mesonsby at least two powers of $p_T$. Similarly, in exclusive production processesat large CM energy and fixed CM angle, the glueball rate dominates by a powerof $s$: we illustrate the method with a simple reaction, $e^-e^+ \to \phi f_0$where the $f_0$ can be tested to be a glueball versus another type of scalarmeson.

Using QCD Counting rules to Identify the Production of Gluonium