We discuss under what circumstances a signal in upcoming laboratory searches for keVscale sterile neutrinos would be compatible with those particles being a sizable part or all of dark matter. In the parameter space that will be experimentally accessible by KA-TRIN/TRISTAN, strong X-ray limits need to be relaxed and dark matter overproduction needs to be avoided. We discuss postponing the dark matter production to lower temperatures, a reduced sterile neutrino contribution to dark matter, and a reduction of the branching ratio in photons and active neutrinos through cancellation with a new physics diagram. Both the Dodelson-Widrow and the Shi-Fuller mechanisms for sterile neutrino dark matter production are considered. As a final exotic example, potential consequences of CPT violation are discussed. a cristina.benso@mpi-hd.mpg.de b vedran.brdar@mpi-hd.mpg.de c manfred.lindner@mpi-hd.mpg.de d werner.rodejohann@mpi-hd.mpg.de 1 In what follows, for brevity, we will refer to such particles simply as "sterile neutrinos". We note that the sterile neutrinos at eV-scale are also well studied in the context of short-baseline neutrino oscillation anomalies [6], but consideration of such states is beyond the scope of this work. 2 see also [14] where this is achieved in the framework of scotogenic model.

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