لخّصلي

The Standard Model (SM) of particle physics has been remarkably successful in describing fundamental particles and their interactions through the electromagnetic, weak, and strong forces.We analyze the BLSSM's extended Higgs sector, which features additional CP-even, CP-odd, and charged Higgs states, and discuss their distinctive collider signatures compared to the SM and MSSM in addition we summeriez The Large Hadron Collider (LHC) and Detector Systems then , A detailed overview of the LHC, the world's most powerful particle accelerator, is provided, covering its design, proton-proton collision mechanics, and operational energies (e.g.,s=13-14 TeV).These gaps motivate the study of BSM theories, particularly SUSY and its extensions, which offer solutions to these problems while preserving the SM's predictive power, then we introduce supersymmetry, a spacetime symmetry that pairs fermions with bosons, and its minimal realization, the Minimal Supersymmetric Standard Model (MSSM).Finally , we display The results and the analysis of the pp->H->bb signal, comparing its luminosity-normalized yield against dominant backgrounds (QCD multijets, tt, Z+jets) to establish significance.Kinematic distributions including the invariant mass (mbb) of b-jet pairs, transverse momentum (pT), and angular separation (?R) are shown for both sm (~125 GeV) and light ( 92 GeV) Higgs hypotheses, with figures highlighting the signal's mass peak and background .We investigate the phenomenological implications of the BLSSM, focusing on Higgs boson production and decay at the Large Hadron Collider (LHC), and assess its detectability through detailed event generation and analysis.Using Monte Carlo (MC) event generators (MadGraph, Pythia, Herwig), we model proton-proton collisions, incorporating higher-order QCD corrections and parton showering.The BLSSM naturally explains neutrino masses via a seesaw mechanism and predicts new particles, including a heavy Z?

The Standard Model (SM) of particle physics has been remarkably successful in describing fundamental particles and their interactions through the electromagnetic, weak, and strong forces. However, several unresolved issuessuch as the hierarchy problem, the nature of dark matter, neutrino masses, and the absence of gravity—suggest the existence of physics beyond the SM (BSM). This thesis explores supersymmetry (SUSY) and its extension, the B-L Supersymmetric Standard Model (BLSSM), as compelling frameworks to address these shortcomings. We investigate the phenomenological implications of the BLSSM, focusing on Higgs boson production and decay at the Large Hadron Collider (LHC), and assess its detectability through detailed event generation and analysis. We begin with a comprehensive review of the SM, emphasizing its theoretical foundations, particle content, and gauge structure. Key successes, such as the prediction of the Higgs boson and electroweak precision tests, are discussed alongside its limitations, including the hierarchy problem, the lack of a dark matter candidate, and the ad-hoc nature of neutrino mass generation. These gaps motivate the study of BSM theories, particularly SUSY and its extensions, which offer solutions to these problems while preserving the SM’s predictive power, then we introduce supersymmetry, a spacetime symmetry that pairs fermions with bosons, and its minimal realization, the Minimal Supersymmetric Standard Model (MSSM). We then present the BLSSM, an MSSM extension that incorporates a gauged U(1)B−L symmetry, where B and L denote baryon and lepton numbers, respectively. The BLSSM naturally explains neutrino masses via a seesaw mechanism and predicts new particles, including a heavy Z′ boson and right-handed sneutrinos. We analyze the BLSSM’s extended Higgs sector, which features additional CP-even, CP-odd, and charged Higgs states, and discuss their distinctive collider signatures compared to the SM and MSSM in addition we summeriez The Large Hadron Collider (LHC) and Detector Systems then , A detailed overview of the LHC, the world’s most powerful particle accelerator, is provided, covering its design, proton-proton collision mechanics, and operational energies (e.g.,s=13−14 TeV). We focus on the ATLAS and CMS detectors, describing their sub-systems (trackers, calorimeters, muon spectrometers) and their roles in reconstructing high-energy events. Special attention is given to triggering mechanisms, particle identification, and key reconstruction algorithms for jets, leptons, and missing transverse energy (MET), which are crucial for SUSY and Higgs searches. After that , we introduces Event Generation and Sampling for Higgs Boson Production.We outline the computational framework for simulating Higgs boson production in the BLSSM. Using Monte Carlo (MC) event generators (MadGraph, Pythia, Herwig), we model proton-proton collisions, incorporating higher-order QCD corrections and parton showering. Detector effects are simulated via Delphes, a fast detector parameterization tool. Key processes studied and we display the cross sections and the fynman diadrams for the simulated signals . Finally , we display The results and the analysis of the pp→H→bb signal, comparing its luminosity-normalized yield against dominant backgrounds (QCD multijets, tt̄, Z+jets) to establish significance. Kinematic distributions including the invariant mass (mbb) of b-jet pairs, transverse momentum (pT), and angular separation (ΔR) are shown for both sm (~125 GeV) and light ( 92 GeV) Higgs hypotheses, with figures highlighting the signal’s mass peak and background .
The pT and η distributions demonstrate the signal’s distinct kinematic features, while cut-flow efficiencies quantify the impact of selections on purity. Statistical significance (S/√B) is evaluated , accounting for systematic uncertainties ( b-tagging, jet energy scale).