Measuring supersymmetry at the large hadron collider

The large hadron collider (LHC) should have the ability to detect supersymmetric particles if low-energy supersymmetry solves the hierarchy problem. Studies of the LHC detection reach, and the ability to measure properties of supersymmetric particles are currently underway. We highlight some of these, such as the reach in minimal supergravity space and correlation with a fine-tuning parameter, precision measurements of edge variables, anomaly or gauge-mediated supersymmetry breaking. Supersymmetry with baryon-number violation seems at first glance more difficult to detect, but proves to be possible by using leptons from cascade decays.     

Singlet-Higgs-Boson signals at hadron colliders

Many extensions of the Standard Model includeSU(2) _L ×U(1) _Y singlet higgs bosons,h ⁰, and also vector-like fermions which couple to it. The production and detection possibilities of such singlet neutral scalars at hadron colliders are considered for different scenarios of vectorlike fermions. We find that for some values of masses and couplings, detection at the CERN large hadron collider (LHC) appears to be a distinct possibility, while at the Fermilab Tevatron upgrade theh ⁰ might be observed only in very favourable circumstances.     

Leptonic signals from off-shellZ boson pairs at hadron colliders

We calculate the invariant amplitudes for the process γ→γ in the full electroweak standard model and present them in concise analytical form. The differential polarized and total unpolarized cross sections are discussed in the MeV region and in the GeV region. The cross section is completely dominated by the fermion contributions at low energies whereas it is determined by the W-boson diagrams at high energies $\left( {\sqrt s \gtrsim 1TeV} \right)$ .