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In this brief review, we summarize the new developments on the description of gluon radiation by energetic quarks traversing a medium as well as the observable consequences in high-energy heavy-ion collisions. Information about the initial state is essential for a reliable interpretation of the experimental results and will also be reviewed. Comparison with experimental data from RHIC and expectation for the future LHC will be given.

Two-jet event shape distributions, traditionally studied in the language of perturbative QCD, can be described naturally in soft-collinear effective theory. In this language, we demonstrate factorization of event shape distributions into perturbatively-calculable hard and jet functions and nonperturbative soft functions, and show how the latter contribute universal shifts to the mean values of various event shape distributions. Violations of universality in shifts of higher moments can give information on correlations of energy flow in soft radiation.

We review up-to-date results on high-p_T particles and jets in heavy-ion collisions by three major LHC experiments, ALICE, ATLAS and CMS. Results of analyses of 2010 and 2011 Pb+Pb data at are discussed. We concentrate mainly on results by fully reconstructed jets and discuss similarities and important differences in measurements among experiments. We point to the importance of understanding the results in a view of difference between quark-initiated and gluon-initiated jets.

We present an implementation of the CMS-EXO-17-015 analysis in the MadAnalysis 5 framework. The analysis targets a search for dark matter in a channel in which it originates from the production and decay of a pair of scalar leptoquarks. This search considers a luminosity ${ℒ}=77.4{\mathrm{\text{fb}}}^{-1}$ of CMS data collected in 2016 and 2017, in proton-proton collisions at a center-of-mass energy of 13 TeV. The final state signature is comprised of one isolated highly-energetic muon, one jet with a large transverse momentum and a significant amount of missing transverse energy. We validate our implementation in MadAnalysis 5 for a specific leptoquark/dark matter benchmark scenario. In particular, we compare predictions obtained with MadAnalysis 5 with the official CMS results for various kinematical distributions relevant for the CMS-EXO-17-015 analysis, as well as detailed cut-flow tables. We have found an excellent agreement.