In the last few years, research hs suggested that
the elusive neutrinos have mass. If this is
indeed the case, there is a possibility of
them also having massive isosinglet
partners; neutral heavy leptons.
These neutral heavy leptons wouldn't interact
via the weak nuclear force, but would rather be
detected after they decay into charged leptons
and neutrinos.
The so-called Karmen experiment at ISIS
(a condensed matter science facility
concentrating on neutron and
muon physics) in Rutherford, UK,
has detected anomalies in the energy deposited
in their detector, which they have
attributed to a possible neutral particle
produced via pion decay. The MiniBooNE
experiment (at Fermi National Accelerator Laboratory)
began collecting data July 31, 2001, and will hopefully
be able to detect this anomaly, as well as
neutral heavy leptons within a larger rage of
masses by searching for their decays.
Sources:
- Neutral Heavy Lepton Search at MiniBooNE;
Sarah Case, Janet Conrad and Michael Shaevitz,
Columbia University
- Google