Related papers: Lightest-neutralino decays in R_p-violating models…
Decays of sneutrinos are considered in the case that in the presence of lepton-number violation in the sneutrino sector the lighter tau-sneutrino is the Lightest Supersymmetric Particle and the Cold Dark Matter in the Universe. In such…
In recent times, several hints of lepton non-universality have been observed in semileptonic $B$ meson decays, both in the charged-current ($b \to c l \bar \nu_l$) and neutral-current ($b \to s ll $) transitions. Motivated by these…
A complete phenomenological study of the next-to-lightest neutralino decays is performed in the MSSM. The widths and branching ratios for all the possible decay channels (including the radiative decay X0(2) --> X0(1) gamma and the decay…
We examine the production and the decay modes of neutralinos and charginos in a softly-broken supersymmetric model with an extra Abelian symmetry U(1)'. We perform the study in a U(1)' model with a secluded sector, where the tension between…
We study signatures of R-parity violation in the production of supersymmetric particles at the LHC, and the subsequent decay of the lightest neutralino being the end product of a supersymmetric cascade decay. In doing so, we pay particular…
In R-parity-violating supersymmetry the lightest neutralino can be very light, even massless. For masses in the range $500$ MeV$\lesssim m_{\tilde\chi^0_1}\lesssim 4.5$ GeV the neutralino can be produced in hadron collisions from rare meson…
We study two CP sensitive triple-product asymmetries for neutralino production e+e- \to \tilde\chi^0_i \tilde\chi^0_j and the subsequent leptonic two-body decays \tilde\chi^0_i \to \tilde{l} l of one of the neutralinos and of the slepton…
We propose an analysis of LEP constraints on radiative neutralino decays into a light gravitino, based on the plane of the Higgs mixing parameter mu and the SU(2) gaugino mass M_2. The preliminary LEP 2W constraints in the (mu, M_2) plane…
A search, in e^+e^- collisions, for chargino, neutralino, scalar lepton and scalar quark pair-production is performed, without assuming R-parity conservation in decays, in the case that only one of the coupling constants lambda_ijk or…
Results are presented from searches for R-parity-violating supersymmetry in events produced in pp collisions at sqrt(s) = 8 TeV at the LHC. Final states with 0, 1, 2, or multiple leptons are considered independently. The analysis is…
Supersymmetry with bilinear R-parity violation provides a predictive framework for neutrino masses and mixings in agreement with current neutrino oscillation data. The model leads to striking signals at future colliders through the R-parity…
Current searches for the top squark mostly focus on the decay channels of $\tilde{t}_1 \rightarrow t \chi_1^0$ or $\tilde{t}_1 \rightarrow b \chi_1^\pm \rightarrow bW \chi_1^0$, leading to $tt/bbWW+\not\mathrel{E}_T$ final states for top…
We compute the neutralino decay rate in the minimal supersymmetric standard model with the addition of explicit R-parity violation. We include the complete squark and slepton mixing matrices, previously neglected, and we improve and correct…
The spectrum of supersymmetric theories with R-parity violation are much more weakly constrained than that of supersymmetric theories with a stable neutralino. We investigate the signatures of supersymmetry at the LHCb experiment in the…
Weak scale supersymmetry is often said to be fine-tuned, especially if the matter content is minimal. This is not true if there is a large A term for the top squarks. We present a systematic study on fine-tuning in minimal supersymmetric…
We consider light neutralinos of mass about 1 GeV, produced from $\tau$ lepton rare decays at Belle II, in the context of R-parity-violating (RPV) supersymmetry. With large and clean samples of $\tau$ leptons produced at the Belle II…
In an interesting class of models, non-renormalizable terms of the superpotential are responsible for the spontanteous breaking of Peccei-Quinn (PQ) symmetry as well as the generation of the $\mu$ term. The flaton fields which break PQ…
We study the distribution of lepton pairs from the second lightest neutralino decay \tchi^0_2\to\tchi^0_1 l^+l^-. This decay mode is important to measure the mass difference between \tchi^0_2 and the lightest neutralino \tchi^0_1, which…
The di-leptons and di-neutrinos observed in the final states of flavor-changing neutral b decays provide an ideal platform for probing physics beyond the standard model. Although the latest measurements of $R_{K^{(*)}}$ agree well with the…
We analyze higher order decay modes of the lightest top squark $\tilde{t}_1$ in the Minimal Supersymmetric extension of the Standard Model (MSSM), where the lightest SUSY particle (LSP) is assumed to be the neutralino $\chi_1^0$. For small…