1202.4036 (Andrew Casey et al.)

Calculating Dihadron Fragmentation Functions in the NJL-jet model    [PDF]

Andrew Casey, Hrayr H. Matevosyan, Anthony W. Thomas

The NJL-jet model provides a framework for calculating fragmentation
functions without the introduction of ad hoc parameters. We develop the NJL-jet
model to investigate dihadron fragmentation functions (DFFs) of the form
$D^{h_1 h_2}_q(z_1,z_2)$. Here we studied DFFs for $q \to \{\pi^+ \pi^-\}$,
$\{\pi^+ K^-\}$, and $\{K^+ K^-\}$,with $q = u, d, s$. The driving terms, which
represent the probability of one of the hadrons being emitted in the first
emission step of the quark-jet hadronization picture, dominate the solutions of
the DFFs where either $z_1$ or $z_2$ is large, and $z_1$ ($z_2$) is the
light-cone momentum fraction of the emitted hadron, $h_1$ ($h_2$). The higher
order terms, which represent the probability of neither of the hadrons being
emitted in the first emission step of the quark-jet, become more significant as
$z_1$ ($z_2$) is lowered. Finally, we present a sample result for QCD evolution
of DFFs, that significantly modify the model solutions when evolved to typical
hadronic scale of $4 \mathrm{GeV}^2$.

View original: http://arxiv.org/abs/1202.4036