  The search at hadron colliders for new massive resonances of a few 100 GeVs
that couple effectively to colored states is an extremely challenging issue,
due principally to the presence of large QCD multijet backgrounds at this
energy, rendering the searches at the LHC particularly difficult. Recently, it
was realized that these large backgrounds could be overcome by demanding one
high-$p_T$ jet from initial-state radiation (ISR) and by means of novel
jet-reconstruction techniques through which the resulting hadronized products
of the massive resonances are reconstructed as a fat-jet, a unique large-radius
jet. The ATLAS and CMS Collaborations have recently reported searches for the
experimental signature of a single fat-jet in association with an ISR jet.
Models of dynamical supersymmetry breaking with an spontaneously broken
R-symmetry give rise to the appearance of a pseudo-Nambu-Goldstone boson called
the R-axion, which naturally tends to be light. In the parameter space regions
where the anomalous R-axion coupling to gluons is boosted, these models can be
tested against these new LHC dijet searches. Taking into account the CMS
search, we apply the $q_\mu$ statistical method to the signal events against
the background-only expectation and obtain the 95\% C.L. exclusion limits on
the most relevant model parameters for a particular messenger sector, namely,
the R-axion mass $m_a$, the decay constant $f_a$, and the number of color
messengers $N$, being these limits suitable to be applied to more general
models with axion-like particles.
