# Spin-dependent constraints on blind spots for thermal singlino-higgsino dark matter with(out) light singlets

## TL;DR

This paper examines how spin-dependent and independent constraints affect the parameter space for thermal singlino-higgsino dark matter, especially in blind spots where direct detection signals are suppressed, considering current and future experiments.

## Contribution

It provides a detailed analysis of constraints on singlino-higgsino dark matter in blind spots, including the impact of light singlet scalars and the potential of upcoming experiments to probe these models.

## Key findings

- LUX sets a lower LSP mass bound of about 300 GeV for certain scenarios.
- XENON1T can probe nearly the entire LSP mass range except a small Z-resonant region.
- Light singlet scalars relax detection constraints, allowing for lower LSP masses.

## Abstract

The LUX experiment has recently set very strong constraints on spin-independent interactions of WIMP with nuclei. These null results can be accommodated in NMSSM provided that the effective spin-independent coupling of the LSP to nucleons is suppressed. We investigate thermal relic abundance of singlino-higgsino LSP in these so-called spin-independent blind spots and derive current constraints and prospects for direct detection of spin-dependent interactions of the LSP with nuclei providing strong constraints on parameter space. We show that if the Higgs boson is the only light scalar the new LUX constraints set a lower bound on the LSP mass of about 300 GeV except for a small range around the half of $Z^0$ boson masses where resonant annihilation via $Z^0$ exchange dominates. XENON1T will probe entire range of LSP masses except for a tiny $Z^0$-resonant region that may be tested by the LZ experiment. These conclusions apply to general singlet-doublet dark matter annihilating dominantly to $t\bar{t}$. Presence of light singlet (pseudo)scalars generically relaxes the constraints because new LSP (resonant and non-resonant) annihilation channels become important. Even away from resonant regions, the lower limit on the LSP mass from LUX is relaxed to about 250 GeV while XENON1T may not be sensitive to the LSP masses above about 400 GeV.