Fusion in the sun results in electron neutrinos and scientists have predicted that if they can measure the electron neutrinos coming from the sun, they can measure the core of the sun. However, early experiments showed that less than half the expected neutrinos were observed on Earth. The idea that the missing electron neutrinos may have transformed into another type or “flavor” came alive.
This conclusion indicates that neutrinos do have some mass, small as it may be, in order for them to oscillate. So a portion of the electron neutrinos emitted from the sun could have changed flavors to muon or tau neutrinos before reaching Earth, thus solving the missing neutrino problem.
But it still doesn’t explain how or why this occurs, Barnes said. “Our goal is to understand the flavor oscillation properties of neutrinos,” he said.
Studying the elusive neutrino will help scientists better understand particle physics, specifically how particles acquire mass, as well as its role in the formation of the universe and its relationship to dark matter.
From a DOE press release.
One is reminded of the drunk looking for his car keys under the street lamp even though he suspects they were lost elsewhere "because the light is better here".
Symmetry considerations suggest a fourth family of fundamental fermions beyond electron, muon, and tauon- there were even two conferences devoted to the subject almost twenty years ago.
You’d think maybe then that given "dark matter" and all the rest, people might give a moment to think perhaps that the missing solar neutrinos might NOT "have" to be in one of the Standard Model slots. If the proposed fourth family has unusual properties (and the "three plus one" principle can be found all across fundamental physics), and if that is where the solar neutrinos are accumulating, then the current effort will fail.
But heck, throwing good money after bad is a time honored tradition in entrenched schools of research, keeping graduate students in beer and pizza.
codemaniac