10 research outputs found
Recent Developments in Supersymmetric Dark Matter
A brief review is given of some of the recent developments in the theoretical
analyses of supersymmetric dark matter. These include the effects of
uncertainties in the wimp velocity and wimp density and of the effects of
uncertainties in the quark densities of the proton. Also analyzed are the
effects of non-universalities in the gaugino sector and their effects on
determining the nature of cold dark matter, i.e., if the neutralino is bino
like, higgsino like, or wino like. The maximum and the minimum elastic
neutralino proton cross sections are discussed and a comparison of the direct
and the indirect detection arising from the capture and annihilation of
neutralinos in the core of the earth and the sun is given. Some of the other
recent developments are summarized.Comment: Based on an invited talk at the conference IDM2000, York, UK, 18-22
September, 2000; 12 pages, Latex and 4 figure
Theoretical Status of Muon (g-2)
The theoretical status of the muon anomaly is reviewed including the recent
change in the light by light hadronic correction. Specific attention is given
to the implications of the shift in the difference between the BNL experimental
result and the standard model prediction for sparticle mass limits. The
implication of the BNL data for Yukawa unification is discussed and the role of
gaugino mass nonuniversalities in the satisfaction of Yukawa unification is
explored. An analysis of the BNL constraint for the satisfaction of the relic
density constraint and for the search for dark matter is also given.Comment: 9 pages, Latex aipproc.Invited plenary talk at the Coral Gables
Conference, at Fort Lauderdale, Florida, Dec 12-16, 2001. Vernon Hughes and
Alan Krisch, session organizer
Gaugino Mass Nonuniversality and Dark Matter in SUGRA, Strings and D Brane Models
The effects of nonuniversality of gaugino masses on dark matter are examined
within supersymmetric grand unification, and in string and D brane models with
R parity invariance. In SU(5) unified models nonuniversality in the gaugino
sector can be generated via the gauge kinetic energy function which may depend
on the 24, 75 and 200 dimensional Higgs representations. We also consider
string models which allow for nonuniversality of gaugino masses and D brane
models where nonuniversality arises from embeddings of the Standard Model gauge
group on five branes and nine branes. It is found that with gaugino mass
nonuniversality the range of the LSP mass can be extended much beyond the range
allowed in the universal SUGRA case, up to about 600 GeV even without
coannihilation effects in some regions of the parameter space. The effects of
coannihilation are not considered and inclusion of these effects may further
increase the allowed neutralino mass range. Similarly with the inclusion of
gaugino mass nonuniversality, the neutralino-proton () cross-section
can increase by as much as a factor of 10 in some of regions of the parameter
space. An analysis of the uncertainties in the quark density content of the
nucleon is given and their effects on cross-section are discussed.
The predictions of our analysis including nonuniversality is compared with the
current limits from dark matter detectors and implications for future dark
matter searches are discussed.Comment: Revised version, 23 pages, Latex, and 7 figure
Supersymmetric Dark Matter and Yukawa Unification
An analysis of supersymmetric dark matter under the Yukawa unification
constraint is given. The analysis utilizes the recently discovered region of
the parameter space of models with gaugino mass nonuniversalities where large
negative supersymmetric corrections to the b quark mass appear to allow
unification for a positive sign consistent with the and constraints. In the present analysis we use the
revised theoretical determination of ()
in computing the difference which takes account of
a reevaluation of the light by light contribution which has a positive sign.
The analysis shows that the region of the parameter space with
nonuniversalities of the gaugino masses which allows for unification of Yukawa
couplings also contains regions which allow satisfaction of the relic density
constraint. Specifically we find that the lightest neutralino mass consistent
with the relic density constraint, unification for SU(5) and
unification for SO(10) in addition to other constraints lies in the region
below 80 GeV. An analysis of the maximum and the minimum neutralino-proton
scalar cross section for the allowed parameter space including the effect of a
new determination of the pion-nucleon sigma term is also given. It is found
that the full parameter space for this class of models can be explored in the
next generation of proposed dark matter detectors.Comment: 28 pages,nLatex including 5 fig