Related papers: Distinguishing between MSSM and NMSSM with e\gamma…
It is shown that a decaying neutralino in a supergravity unified framework is a viable candidate for dark matter. Such a situation arises in the presence of a hidden sector with ultraweak couplings to the visible sector where the neutralino…
We discuss the production of charginos, neutralinos, and third generation sfermions in $e^+e^-$ annihilation in the energy range $\sqrt{s} = 0.2-1$ TeV. We present numerical predictions within the Minimal Supersymmetric Standard Model for…
The Next-to-Minimal Supersymmetric Standard Model (NMSSM) includes a Higgs iso-singlet superfield in addition to the two Higgs doublet superfields of the minimal extension. If the Higgs fields remain weakly coupled up to the GUT scale, as…
We investigate the constraints to the light neutralino dark matter scenario in the minimal supersymmetric standard model from available experimental observations such as decays of B and K meson, relic dark matter abundance, and the search…
We present two scenarios in the Minimal Supersymmetric Extension of the Standard Model (MSSM) that can lead to an explanation of the excess in the invariant mass distribution of two opposite charged, same flavor leptons, and the…
The scattering of neutrinos off dark matter can induce time delays in their propagation compared to that of photons, which would wash out correlations between ultra-high-energy neutrinos and electromagnetic observations of their sources -…
We study the process e^+ e^- -> chi^0_1 chi^0_2 and the subsequent decay chi^0_2 -> chi^0_1 l^{+} l^{-}$ with polarized beams, including the complete spin correlations of chi^0_2$. We present numerical results for the lepton energy and…
We investigate new physics with light-neutral mediators through coherent elastic neutrino-nucleus scattering (CE$\nu$NS) at low energies. These mediators, with a mass of less than $1$ GeV, are common properties for extensions of the…
Decays of the lightest neutralino are studied in R_p-violating models with operators lambda^{prime} L Q D^c and lambda L L E^c involving third-generation matter fields and with dominant lambda^{prime} and lambda couplings. Generalizations…
The pair production of tau sneutrinos in $e^{+}e^{-}$ collisions and their subsequent decays are studied in a framework of the supersymmetric extension of the standard model. We present an analysis for the parameter space (BR vs. mass)…
Motivated by recent claims of lines in the Fermi gamma-ray spectrum, we critically examine means of enhancing neutralino annihilation into neutral gauge bosons. The signal can be boosted while remaining consistent with continuum photon…
We compare the rate for elastic scattering of neutralinos from various nuclei with the flux of upward muons induced by energetic neutrinos from neutralino annihilation in the Sun and Earth. We consider both scalar and axial-vector…
We study neutralino sectors in extensions of the MSSM that dynamically generate the mu-term. The extra neutralino states are superpartners of the Higgs singlets and/or additional gauge bosons. The extended models may have distinct lightest…
The signatures for low energy supersymmetry breaking at the Tevatron are investigated. It is natural that the lightest standard model superpartner is an electroweak neutralino, which decays to an essentially massless Goldstino and photon,…
The discovery potential for detecting new heavy Majorana and Dirac neutrinos at some recently proposed high energy $e^+e^-$ colliders is discussed. These new particles are suggested by grand unified theories and superstring-inspired models.…
We study the phenomenology of a Standard Model (SM) extension with two charged singlet scalars and three right handed (RH) neutrinos at an electron-positron collider. In this model, the neutrino mass is generated radiatively at three-loop,…
We show that the process $e^+e^- \to \gamma+$ missing energy, arising from the pair production of neutralinos, can probe the $\gamma-\tilde\gamma- \gravitino$ as well as the $Z-\tilde Z-\gravitino$ couplings in Gauge Mediated Supersymmetry…
We study the production and leptonic decay of charginos in collisions of polarized photon beams including the complete spin correlations. The photons can be generated by Compton backscattering of polarized laser pulses off a polarized…
We study chargino production e^+ e^- -> chi^+_1 chi^-_1 and the subsequent leptonic decay chi^-_1\to chi^0_1 e^- nu_e including the complete spin correlations between production and decay. We work out the advantages of polarizing the e^+…
A two-component dark matter model is studied adopting the degenerate scenario in the R-parity conserving NMSSM. The gravitino LSP and the neutralino NLSP are extremely degenerate in mass, avoiding the BBN bounds and obtaining a high…