  Collisions of heavy ion nuclei at relativistic speeds (close to the speed of
light) creates a high temperature and very dense form of matter, now known to
consist of de-confined quarks and gluons, named the quark gluon plasma (QGP).
In this thesis, Run1 experimental data from pp and heavy ion collisions at the
CERN LHC is analyzed with the CMS detector. The pp jet cross section is
compared with next to leading order theoretical calculations supplemented with
non perturbative corrections for three different jet radii highlighting better
comparisons for larger radii jets. Measurement of the jet yield followed by the
nuclear modification factors in proton-lead at 5.02 TeV and lead-lead
collisions at 2.76 TeV are presented. A new data driven technique is introduced
to estimate and correct for the fake jet contribution in PbPb for low
transverse momenta jets. The nuclear modification factors studied in this
thesis show jet quenching to be attributed to final state effects, have a
strong correlation to the event centrality, a weak inverse correlation to the
jet transverse momenta and an apparent independence on the jet radii in the
kinematic range studied. These measurements are compared with leading
theoretical model calculations and other experimental results at the LHC
leading to unanimous agreement on the qualitative nature of jet quenching. This
thesis also features novel updates to the Monte Carlo heavy ion event generator
JEWEL (Jet Evolution With Energy Loss) including the boson-jet production
channels and also background subtraction techniques to reduce the effect of the
thermal background. Keeping track of these jet-medium recoils in JEWEL due to
the background subtraction techniques significantly improves its descriptions
of several jet structure and sub-structure measurements at the LHC. [Shortened
abstract]
