We study the inclusive production at future hadron supercolliders of the standard-model Higgs boson in the intermediate-mass region ( M w 5 M , 5 2 M z ) and its subsequent decay into two virtual W bosons that decay leptonically. Backgrounds from continuum W pair production and from topquark pair production with semileptonic decays are investigated. We conclude that the Higgsboson signal may be observed via the decay H -W* W*-(IV~ ) (?v1,) at the Superconducting Super Collider for 145 GeV < M, 5 2Mz if m, > 150 GeV. Here W * denotes an on-or off-shell W boson.

We investigate the pair production of charged heavy leptons via photoninduced processes at the proposed CERN Large Hadron Collider (LHC). Using effective photon and Z approximations, rates are given for L + L − production due to γγ fusion and Zγ fusion for the cases of inelastic, elastic and semielastic pp collisions. These are compared with the corresponding rates for production via the gluon fusion and Drell-Yan mechanisms. Various γγ and Zγ differential luminosities for pp collisions are also presented.

Small neutrino masses can arise in some grand unified models or superstring theories. We consider a model with an enhanced fermion sector containing Dirac neutral heavy leptons. The dependence on the mass and mixing parameters of these new fermions is investigated for several measurable quantities.We study the flavor-conserving leptonic decays of the Z boson and universality breaking in these decays. We also consider the W boson mass dependence on neutral heavy lepton parameters. PACS numbers(s): 12.15.Ff, 13.38.Dg

One interesting method of constraining the dense matter Equations of State is to measure the advancement of the periastron of the orbit of a binary radio pulsar (when it belongs to a double neutron star system). There is a great deal of interest on applicability of this procedure to the double pulsar system PSR J0737-3039 (A/B). Although the above method can be applied to PSR A in future within some limitations, for PSR B this method can not be applied. On the other hand, the study of genesis of PSR B might be useful in this connection and its low mass might be an indication that it could be a strange star.

We consider the ghost-condensate model of dark energy with a generic potential term. The inclusion of the potential is shown to give greater freedom in realising the phantom regime. The self-consistency of the analysis is demonstrated using WMAP7 + BAO + Hubble data.