Related papers: Higher Order Top Squark Decays
We study the discovery potential of the flavor-changing neutral coupling (FCNC) htc of the Higgs boson and the top quark through the rare tree-body decay h -> Wbc at Muon colliders for a light Higgs boson with mass 114 < m_h < 145 GeV. This…
Neutralinos $\tilde{\chi}^0$ in supersymmetric theories, the spin--1/2 Majorana--type superpartners of the U(1) and SU(2) neutral electroweak gauge bosons and SU(2) neutral Higgs bosons, are expected to be among light supersymmetric…
We point out that charged Higgs bosons can decay into final states different than $\tau^+ \nu_\tau$ and $c \bar{s}$, even when they are light enough to be produced at LEPII or at the Tevatron, through top-quark decays. These additional…
We compute the partial width of the FCNC top quark decay t->c h in the framework of the Minimal Supersymmetric Standard Model, where h = h0, H0, A0 is any of the neutral Higgs of the MSSM. We include the SUSY electroweak, Higgs, and…
The Minimal Supersymmetric Standard Model opens the possibility of electroweak baryogenesis provided that the light scalar top quark (stop) is lighter than the top quark. In addition, the lightest neutralino is an ideal candidate to explain…
We investigate the phenomenology of top squarks at the Large Hadron Collider (LHC) in a supersymmetric model where lepton number is identified with an approximate $U(1)_R$ symmetry in such a way that one of the left chiral sneutrinos can…
We perform for the Large Hadron Collider (LHC) a detailed study of charged Higgs boson production via the top-bottom quark associated mode followed by decays into a chargino and a neutralino, with masses and couplings as given by the…
Restrictive upper bounds on the heavy bottom squark mass when the gluino and one bottom squark are both light are based on the predicted reduction of $R_b$ (the fraction of $Z$ hadronic decays to $b \bar b$ pairs) in such a scenario. These…
The heaviness of the top quark makes its 2-body decay mode $t \to bW^+$ to be dominant, at such level that hardly any other decay mode reaches a detectable branching ratio (BR) within the SM. Here we study the decay $t \to bW^+\ell^-\ell^+$…
In extended Higgs models, the Higgs boson may decay into a pair of light CP-odd scalars, with distinctive collider signatures. We study the ensuing Higgs signals at the upgraded Tevatron, considering the subsequent decays of the scalars…
Searching for Z' bosons, predicted in GUT-inspired U(1)' gauge models and in the Sequential Standard Model, is one of the main challenges of the experiments carried out at the Large Hadron Collider. Such searches have so far focused on…
The lighter superpartner of the top quark ($\tt_1$) may be considerably lighter than squarks of the first two generations, and hence may be accessible to Tevatron collider searches, even if the other squarks and the gluino are too heavy.…
We present a determination of a new class of three-loop Feynman diagrams describing heavy-to-light transitions. We apply it to find the O(alpha_s^2) corrections to the top quark decay t -> bW and to the distribution of lepton invariant mass…
Theoretical predictions for the decay width of Standard Model Higgs boson into bottom quarks and tau-leptons, in the case when M_H< 2M_W, are briefly reviewed. The effects of higher order perturbative QCD (up to alpha_s^4-level) and QED…
We study CP asymmetries in two-body decays of top squarks into neutralinos and sleptons at the LHC. These asymmetries are used to probe the CP phases possibly present in the stop and neutralino sector of the Minimal Supersymmetric Standard…
The scalar partner of the top quark (the stop) is relatively light in many models of supersymmetry breaking. We study the production of stops at the Large Hadron Collider (LHC) and their subsequent decays through baryon-number violating…
We study the decay of a standard model-like Higgs boson into a gravitino and a neutralino, which subsequently decays promptly into another gravitino and a photon. Such a decay can be important in scenarios where the supersymmetry breaking…
The calculation of the partial width of the rare t-quark decay into Upsilon-meson, W-boson and b-quark (t -> \Upsilon W b) is presented. The branching ratio equals Br(t -> Upsilon W b) = 1.3 * 10^{-5} that make possible searches for this…
Decays of heavy mesons and of heavy hyperons are used to provide tests of the standard model and information about new mixing schemes for the $\eta$ and $\eta^{'}$ mesons. These include the two body decays $B_s \to J / \psi M$ and $B_d \to…
The apparent excess of $Z \rightarrow b \bar b$ events at LEP may be an indication of new physics beyond the standard model. However, in either the two-Higgs-doublet model or the minimal supersymmetric standard model, any explanation would…