Appendix 1
All fundamental particles have an intrinsic property known as spin which is a form of angular momentum. It differs from classical angular momentum in that a point particle cannot be described as spinning (as it has radius 0). Most particles can exist in one of two spin states. However, the neutrino has only ever been observed in one of these two states. Conversely the antineutrino has only been detected in the other one of these states. This suggests that they are distinct, despite the fact that they have no charge, which distinguishes most matter and antimatter particles (below). On the other hand for a particle moving at less than the speed of light (as all massive particles do) it is possible change the spin state of the particle by altering your frame of reference. This is because if you travel faster than the particle it seems to travel in the opposite direction and therefore would appear to be spinning in the opposite direction. If it were the case that the spin state distinguished neutrinos from antineutrinos then by changing your reference frame you would have converted the neutrino to an antineutrino.
Faster - neutrino appears right- handed, antineutrino appears left- handed
Slower – neutrino appears left- handed, antineutrino appears right- handed
Left-Handed Neutrinos http://hyperphysics.phy-astr.gsu.edu/hbase/particles/neutrino3.html
32
Made with FlippingBook - Online Brochure Maker