A Deeper Probe of New Physics Scenarii at the LHC

International audienceThe implications of the discovery of a Higgs boson at the LHC with a mass of 125GeV are summarised in the context of the Standard Model of particle physics andin new physics scenarios beyond it, taking the example of the minimalsupersymmetric Standard Model extension, the MSSM. The perspectives for Higgsand new physics searches at the next LHC upgrades as well as at future hadronand lepton colliders are then briefly summarized. Povzetek. Avtor povzameposledice odkritja higgsovega bozona z maso 125 GeV na pospeševalniku LHC vkontekstu standardnega modela osnovnih delcev in scenarijev možne nove fizikeonkraj tega modela. Kot primer vzame minimalno supersimetrično razširitevstandardnega modela znano kot MSSM. Pregleda obete za iskanje znakov nove fizikev naslednji nadgradnji LHC in na bodočih leptonskih in hadronskihpospeševalnikih. The ATLAS and CMS historical discovery of a particle with amass of 125 GeV [1] and properties that are compatible with those of a scalarHiggs boson [2,3] has far reaching consequences not only for the Standard Model(SM) but also for new physics models beyond it. In the SM, electroweak symmetrybreaking is achieved spontaneously via the Brout–Englert–Higgs mechanism [2],wherein the neutral component of an isodoublet scalar field acquires a non–zerovacuum expectation value v. This gives rise to nonzero masses for the fermionsand the electroweak gauge bosons while preserving the SU(2)×U(1) gauge symmetry.One of the four degrees of freedom of the original isodoublet field, correspondsto a physical particle [3]: a scalar boson with J PC = 0 ++ quantum numbersunder parity and charge conjugation. The couplings of the Higgs boson to thefermions and gauge bosons are related to the masses of these particles and arethus decided by the symmetry breaking mechanism. In contrast, the Higgs massitself M H , although expected to be in the vicinity of the weak scale v ≈ 250GeV, is undetermined. Le