Ran Lu

PAMELA satellite data as a signal of non-thermal wino LSP dark matter

Abstract Satellite and astrophysical data is accumulating that suggests and constrains interpretations of the dark matter of the universe. We argue there is a very well motivated theoretical framework (which existed before data) consistent with the interpretation that dark matter annihilation is being observed by the PAMELA satellite detector. The dark matter is (mainly) the neutral W boson superpartner, the wino. Using the program GALPROP extensively we study the annihilation products and the backgrounds together. A wino mass approximately in the 180–200 GeV range gives a good description of the PAMELA data, with antimatter and gammas from annihilating winos dominating the data below this energy range but not contributing above it. We explain why PAMELA data does not imply no antiproton signal was observed by PAMELA or earlier experiments, and explain why the antiproton analysis was misunderstood by earlier papers. Wino annihilation does not describe the Fermi e + + e − data (except partially below ∼100 GeV). At higher energies we expect astrophysical mechanisms to contribute, and we simply parameterize them without a particular physical interpretation, and check that the combination can describe all the data. We emphasize several predictions for satellite data to test the wino interpretation, particularly the flattening or turndown of the positron and antiproton spectra above 100 GeV. It should be emphasised that most other interpretations require a large rise in the positron and antiproton rates above 100 GeV. We focus on studying this well-motivated and long predicted wino interpretation, rather than comparisons with other interpretations. We emphasize that interpretations also depend very strongly on assumptions about the cosmological history of the universe, on assumptions about the broader underlying theory context, and on propagation of antiprotons and positrons in the galaxy. The winos PAMELA is observing arose from moduli decay or other non-thermal sources rather than a universe that cooled in thermal equilibrium after the big bang. Then it is appropriate to normalize the wino density to the local relic density, and no “boost factors” are needed to obtain the reported PAMELA rates.

Geometric compatibility of IceCube TeV-PeV neutrino excess and its galactic dark matter origin

A bstractWe perform a geometric analysis for the sky map of the IceCube TeV-PeV neutrino excess and test its compatibility with the sky map of decaying dark matter signals in our galaxy. We have found that a galactic decaying dark matter component in general improve the goodness of the fit of our model, although the pure isotropic hypothesis has a better fit than the pure dark matter one. We also consider several representative decaying dark matter, which can provide a good fit to the observed spectrum at IceCube with a dark matter lifetime of around 12 orders of magnitude longer than the age of the universe.

A new (string motivated) approach to the little hierarchy problem

Abstract We point out that in theories where the gravitino mass, M 3 / 2 , is in the range (10–50) TeV, with soft-breaking scalar masses and trilinear couplings of the same order, there exists a robust region of parameter space where the conditions for electroweak symmetry breaking (EWSB) are satisfied without large imposed cancellations. Compactified string/M-theory with stabilized moduli that satisfy cosmological constraints generically require a gravitino mass greater than about 30 TeV and provide the natural explanation for this phenomenon. We find that even though scalar masses and trilinear couplings (and the soft-breaking B parameter) are of order (10–50) TeV, the Higgs vev takes its expected value and the μ parameter is naturally of order a TeV. The mechanism provides a natural solution to the cosmological moduli and gravitino problems with EWSB.

Higgs Mass Prediction for Realistic String/M Theory Vacua

Recently it has been recognized that in compactified

Top channel for early supersymmetry discovery at the LHC

\mathrm{\text{string}}/M

Dark matter as a guide toward a light gluino at the LHC

theories that satisfy cosmological constraints, it is possible to derive some robust and generic predictions for particle physics and cosmology with very mild assumptions. When the matter and gauge content below the compactification scale is that of the minimal supersymmetric standard model (MSSM), it is possible to make precise predictions. In this case, we predict that there will be a single standard model-like Higgs boson with a calculable mass

Improving SUSY spectrum determinations at the LHC with the wedgebox technique

105\text{ }\text{ }\mathrm{GeV}\ensuremath{\lesssim}{M}_{h}\ensuremath{\lesssim}129\text{ }\text{ }\mathrm{GeV}

Theory and phenomenology of μ in M theory

depending on

Review and update of the compactified M/String theory prediction of the Higgs boson mass and properties

\mathrm{tan}\ensuremath{\beta}

Three Twin Neutrinos: Evidence from LSND and MiniBooNE

(the ratio of the Higgs vevs in the MSSM). For