Ah, sorry, wires crossed in my head. I think you were asking for information about cosmic neutrino background detectability versus astrophysical/indirect evid

Ah, sorry, wires crossed in my head. I think you were asking for information about cosmic neutrino background detectability versus astrophysical/indirect evidence, right? On the latter: https://arxiv.org/abs/1412.5948 https://arxiv.org/abs/1412.5948 On direct detection: KATRIN collaboration: https://arxiv.org/abs/1602.03347 https://arxiv.org/abs/1602.03347 KATRIN is pretty cool. Pretty pictures of some of the apparatus: http://www.dw.com/en/the-katrin-tritium-neutrino-experiment-a-giant-scale-for-the-tiniest-of-particles/a-36044018 http://www.dw.com/en/the-katrin-tritium-neutrino-experiment-... But KATRIN is to detect warm neutrinos from a known source. As noted in the collab's paper (preprint link above), detecting ambient cold neutrinos would require a different, and larger, apparatus. We may need something much bigger even than that for direct neutrino-like cold dark matter detection. :-( So that gives you a sense of physical scale of what "low hanging fruit" might entail. ETA: also wikipedia is reasonable on this point https://en.wikipedia.org/wiki/Cosmic_neutrino_background?oldformat=true#Indirect_evidence_for_the_C%CE%BDB https://en.wikipedia.org/wiki/Cosmic_neutrino_background?old...