  The neutralino sector of the semi-constrained next-to-minimal supersymmetric
standard model is explored under recent experimental constraints, with special
attention to dark matter (DM) limits. The effects of the upper and lower bounds
of dark matter relic density and recent direct detection constraints on
spin-independent and -dependent cross-sections are thoroughly analyzed.
Particularly, we show which regions of the parameter space are ruled out due to
the different dark matter constraints and the corresponding model-specific
parameters: $\lambda, \kappa, A_{\lambda}$, and $A_{\kappa}$. We analyze all
annihilation and co-annihilation processes (with heavier neutralinos and
charginos) that contribute to the dark matter relic density. The mass
components of the dark matter candidate, the lightest neutralino
$\tilde{\chi}_1^0$, are studied, and the decays of heavy neutralinos and
charginos, especially $\tilde{\chi}_2^0$ and $\tilde{\chi}_1^+$, into the
lightest neutralino are examined. We impose semi-universal boundary conditions
at the Grand Unified Theory scale and require a moderate range of $\tan{\beta}
\lesssim 10$. We find that the allowed parameter space is associated with a
heavy mass spectrum in general and that the lightest neutralino is mostly
Higgsino with a mass range that resides mostly between 1000 and 1500 GeV.
However, smaller mass values can be achieved if the DM candidate is bino-like
or singlino-like.
