sci.physics.particle

I was watching an astronomy tv show over the weekend, talking about when
the mass of a star is large enough, when it "dies", the electrons will
combine with the protons of the atoms, creating nothing but a dense pack
of neutrons. The resulting "rebound" off this neutron core creates a
super nova, and that there are neutrinos (sorry for botching the spelling
so bad) that "push" material away from the star.

I know that sub-atomic particles like protons and electrons are made up of
three quarks each, as is a neutron. I no longer have my old college
physics book, so I cannot look it up myself, and I have so far been unable
to find a web reference to answer my question.

That question is, when the three quarks of the electron and the three
quarks of the proton combine, creating a neutron... What sub-atomic
particle do the three "left over" quarks create? Is it a neutrino? Have
they actually been discovered? Last time I knew, they were theorized, but
never actually "seen". Or am I just totally wrong?