Um, how? Using Dark Matter detectors? Look, neutrinos couple to existing, known particles -- leptons, although via other more complex processes e.g. inverse beta decay they can couple to protons in nuclei as well. The response we can detect is in proportion to the density of those particles in a medium that can function as a detector, which in turn is proportional to straight up mass density. The interaction probability is phenomenally low for all of the known particles, so one requires large volumes of material to make ANY kind of detector. There are strict limits on the density of ordinary matter, and even more stringent limits on the density of matter that can conceivably used as a detector
So I'm curious -- given that the ratio between the mass density of water and the mass density of e.g. Tungsten, Uranium, Plutonium is only a single order of magnitude, and a reaction cross section that AFAIK depends solely on the mass density, where exactly are the other two orders of magnitude going to come from from any possible variation in materials?
"Systems", well, perhaps. If we use underground cavities filled with water to look for Cerenkov radiation, or chlorine detectors to look for outgassing Argon, we can always make them 10x bigger and hence increase the detector volume 1000 fold. But this is morally equivalent to building 1000 detectors like we have today and combining the data, and it still leaves us with the same issues if one wishes to determine flavor information and not just raw e.g. neutral current flux. Indeed, to get flavor information we will very likely be limited to building 1000 detectors to get 1000 fold increase in data simply because there are size constraints on detectors that are going to detect and resolve e.g. a muon produced in a charged current interaction.
So sure, we can always scale up our existing technology or minor improvements of it to improve detection rates. But I don't think that materials or systems that improve the scaling of the detection technologies we already have are particularly plausible, based on what I now know. So what did you have in mind (as in, do you know something I don't)? Are there other materials that are likely to have orders of magnitude higher cross section for inverse beta decay, or are you just thinking of building bigger/more detectors?
Not flames, BTW -- an honest question.
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