Comment by ww520

Most paths of the high energy observable collisions follow a very close alignment to the original neutrino's path. The forward momentum of a high energy neutrino completely dominates the collision. Imagine an one-ton ball hitting a billiard ball. Doesn't matter what direction the billiard ball was going; the resulting path is the one-ton ball's path.

In other cases, the particle being collided is scattered and won't show up in the detector. Low energy neutrino collisions also have very faint light and difficult to detect. Solar system produced neutrinos are in this category.