相关论文: Radiative Neutralino Decay in Split Supersymmetry

It is pointed out that there is a strong correlation between the neutralino dark matter scattering cross section $\sigma_{\tilde{\chi} p}$ and the branching ratio for $B_s \to \mu^+ \mu^-$ within minimal supergravity (mSUGRA) and its…

Present neutrino data are consistent with neutrino masses arising from a common seed at some ``neutrino unification'' scale $M_X$. Such a simple theoretical ansatz naturally leads to quasi-degenerate neutrinos that could lie in the…

Radiative corrections to neutrino mixings in seesaw models depend on the nature of new physics between the weak and the GUT-seesaw scales and can be taken into account using the renormalization group equations. This new physics effect…

Supersymmetric radiative neutrino mass models have often two dark matter candidates. One is the usual lightest neutralino with odd R parity and the other is a new neutral particle whose stability is guaranteed by a discrete symmetry that…

We study a particular texture of the neutrino mass matrix generated in supergravity with bilinear R-Parity violation. The relatively high value of $\tan\beta$ makes the one-loop contribution to the neutrino mass matrix as important as the…

We consider how, for quasi-degenerate neutrinos with tri-bi-maximal mixing at a high-energy scale, the mixing angles are affected by radiative running from high to low-energy scales in a supersymmetric theory. The limits on the high-energy…

The $B-L$ MSSM is the MSSM with three right-handed neutrino chiral multiplets and gauged $B-L$ symmetry. The $B-L$ symmetry is broken by the third family right-handed sneutrino acquiring a VEV, thus spontaneously breaking $R$-parity. Within…

We study the radiative $\rho^0\to \pi^+\pi^-\gamma$ and $\rho^0\to \pi^0\pi^0\gamma$ decays and we calculate their branching ratios using a phenomenological approach by adding to the amplitude calculated within the framework of chiral…

For the first time, a full one-loop calculation of the process $\chi\chi\to 2\gamma$ is performed, where $\chi$ is the lightest neutralino in the minimal supersymmetric extension of the Standard Model. This process is of interest for dark…

We study the production of the lightest neutralinos in the radiative process $e^+e^- \to \tilde\chi^0_1 \tilde\chi^0_1\gamma$ in low energy supersymmetric models for the International Linear Collider energies. This includes the minimal…

We present the results of the complete one-loop computation of the $B^0_{d,s}\to l^+l^-$ decay rate in the MSSM. Both sources of the FCNC, the CKM matrix and off-diagonal entries of the sfermion mass matrices are considered. Strong…

We study radiative neutralino production e^+e^- \to \tilde\chi^0_1 \tilde\chi^0_1\gamma at the linear collider with longitudinally polarised beams. We consider the Standard Model background from radiative neutrino production e^+e^- \to \nu…

Neutrino disappearance measurements using binned reconstructed-energy spectra exhibit a regime in which small mass-squared splittings become unidentifiable at quadratic order when smooth spectral shape uncertainties are represented by…

Extending the Higgs sector of the MSSM by the addition of a gauge singlet scalar field can remedy the mu problem. We explore the implications of extended models for both the spectrum of the neutralinos and the cascade decays of the…

We compute analytically the tree-level annihilation rates of a collection of non-relativistic neutralino and chargino two-particle states in the general MSSM, including the previously unknown off-diagonal rates. The results are…

Dark matter decays into invisible particles can leave an imprint in large-scale structure surveys due to a characteristic redshift-dependent suppression of the power spectrum. We present a model with two quasi-degenerate singlet fermions,…

We determine the radiative corrections to the masses of the gauginos and Higgsinos in the MSSM, including all sectors of the theory in a one-loop calculation in the on-mass-shell renormalization scheme. We find that a gluino which is…

We consider a sterile neutrino to be an unparticle, namely an \emph{unsterile neutrino}, with anomalous dimension $\eta$ and study its mixing with a canonical active neutrino via a see-saw mass matrix. We show that there is \emph{no…

I review the NLO QCD calculations of the branching ratio for B--> X_s gamma in the SM. Including the leading electromagnetic corrections, one obtaines BR(B-> X_s gamma)=(3.32 +- 0.30)*10^{-4}. Confronting theory with the newest data, an…

A brief review is given of the recent developments in the analyses of supersymmetric dark matter. Chief among these is the very accurate determination of the amount of cold dark matter in the universe from analyses using WMAP data. The…