Speaker
Eva Ziebarth
(Karlsruhe Institute of Technology)
Description
The neutralino is the lightest supersymmetric particle in many SUSY models. Thus in R parity
conserving models it provides a perfect dark matter candidate by being electromagnetically
neutral, weakly interacting and stable. Following cosmological models, at the freeze-out time
most neutralinos should have been transformed into standard model particles by annihilation.
The annihilation cross section is inversely proportional to the observed dark matter density and
thus precisely known.
In case SUSY will be discovered at the LHC, it is not a proof that the neutralino is the dark
matter existing in the universe. But to get a hint one can try to determine the neutralino an-
nihilation cross section from LHC data and see if it is consistent with the annihihilation cross
section corresponding to the relic density, as discussed above.
It is shown that in a large region of parameter space this cross section is dominated by pseudos-
calar Higgs exchange and the correct value can only be obtained for values of tanβ around 50.
This would lead o a large cross section for pseudoscalar Higgs production, which is proportional
to tanβ squared.
This cross section or the width of the pseudoscalar Higgs can be exploited to determine tanβ
and thus determine the annihilation cross section in the regions without co-annihilation or very
light squarks and sleptons. In the latter case the t-channel would dominate, but this region is
already excluded by the Higgs limits and other electroweak constraints.
Primary author
Eva Ziebarth
(Karlsruhe Institute of Technology)
Co-authors
Conny Beskidt
(Karlsruhe Institute of Technology)
Dmitri Kazakov
(Joint Institute for Nuclear Research)
Tim Hanisch
(Karlsruhe Institute of Technology)
Prof.
Wim de Boer
(Karlsruhe Institute of Technology)
