The phrase "ray activity" refers to the level of movement or action in a specific area, similar to rays of light spreading out in different directions. It indicates how lively or busy something is. Full definition
More pointedly, Cayce Boone, the 46 - year - old Navajo who founded the lodge and obtained a Forest Service permit for it 9 years ago, declared recently that «gamma ray activity and our spiritual practices are not compatible.» (sciencemag.org)
In fact, the contribution of decreasing cosmic ray activity to climate change is almost 40 per cent, argues Dr. Rao in a paper which has been accepted for publication in Current Science, the preeminent Indian science journal. (drtimball.com)
Co2 levels also follow cosmic ray activity and solar cycle from peak co2 to peak co2. (judithcurry.com)