Here are some interesting links to research on astrophysical candidates for the dark matter.
Kashlinsky has a recent paper published in ApJ (24 May 2016) that discusses a possible relationship among the topics of the DM, PBHs and background radiations. http://arxiv.org/abs/1605.04023 . One can search arxiv.org for papers on PBHs that have sprung up since the LIGO discoveries.
Additionally, M.R.S. Hawkins has offered a cogent and empirically-supported case for stellar-mass and planetary-mass ultracompacts (with primordial black holes being the most likely candidates) as the mystery objects causing microlensing events seen in galactic bulge, galactic halo and quasar research. [papers available for free: http://arxiv.org/abs/1106.3875 and http://arxiv.org/abs/1503.01935 .
A huge population of primordial black holes satisfies the non-baryonic constraint, might also explain where cosmic rays primarily come from, and might explain why the ARCADE-2 experiment found a unexplained factor-of-6 excess in cosmological radio emission, the sources of fast radio bursts, etc.
Somewhat dated but still of interest: https://arxiv.org/ftp/astro-ph/papers/0002/0002363.pdf
http://www.academia.edu/2917630/Predictions_of_Discrete_Scale_Relativity