Speaker
Ms
Ghazal Ghafari
(Bonn University)
Description
We postulate the WIMP neutralino Dark Matter's interaction with ordinary matter as scattering from the direct detection experiments' nucleon target. Recently, one of the most sensitive direct detection experiments XENON1T submitted an upper bound on the WIMP-Nucleon Spin-Independent elastic cross-section $ \sigma_{SI} $ at $ 4.1 \times 10^{-47} GeV^2 $ for a mass of $ 30 \frac{GeV}{c^2} $. We imply the last XENON1T results and naturalness constraints to settle a lower bound on Higgsino mass parameter $\mu$.
Results indicated that the lower bound on $|\mu|$ from direct WIMP
searches is only slightly above $M_1$, especially for $\mu < 0$.
As e consequence, the bino approximation, especially for the negative sign of $\mu$ diverges for $|\mu|\rightarrow|M_1|$ where it occurs by increasing $M_1$ in the lower limit of $\mu $ formalism. Instead, we introduce a new approximation, a strong mixture, working in small $|\mu|-|M_1|$ that performs even better for the negative sign of $\mu$.
Primary author
Ms
Ghazal Ghafari
(Bonn University)
Co-author
Prof.
Manuel Drees
(Bonn University)
