Search for resonance in inclusive and b-tagged dijet mass spectra in proton-proton collision at $\sqrt{s}$ = 13 TeV and constraints on dark matter and other models

Two analyses searching for new heavy resonances and interpreting the result with dark matter are presented in this dissertation. The first analysis searches for resonances decaying into dijet final states using the proton-proton collision data at center mass of $\sqrt{s}$ = 13 TeV with the CMS detector at Large Hadron Collider in 2016, corresponding to a total integrated luminosity of 36 fb$^{−1}$. No significant evidence for the production of new particles is observed. A simplified model of interactions between quarks and dark matter is used to interpret the result. The second analysis searches for resonances decaying into dijet final states using the proton-proton collision data at center mass of $\sqrt{s}$ = 13 TeV with the CMS detector at Large Hadron Collider in 2016, 2017, and 2018, corresponding to a total integrated luminosity of 137.5 fb−1. A b-tagger named DeepJet is used to examine the events with jets containing B hadrons. No evidence of new heavy resonances is observed, as well. The 95% confidence level cross-section upper limit is set on excited b-quark b$^{∗}$ and Coloron models. Limits are also set on a simplified model of interactions between b-quarks and dark matter.