I have very similar properties to the electron, but I am 207 times heavier and unstable. I am created when a proton with high energy ejected from the sun hits the atmosphere.
I can fly through galaxies without losing energy and I can transform into an electron neutrino or tau neutrino through the so-called neutrino oscillations.
Since we rarely interact, we can travel very long distances without being influenced. I could travel through a piece of lead from here to the Alpha Centauri, and not stop.
Like all quarks, I never come alone. I combine with other quarks to form new particles. Together with the up quark and the electron we are the building blocks of matter.
Quarks and we anti-quarks destroy each other. Anti-matter is almost non-existent in the universe. This is due to an asymmetry at the beginning of the universe.
Anti-matter is matter that consists of anti-particles. Anti-atoms have atomic shells of positrons and atomic nuclei of anti- up and anti- down quarks, which form the anti-protons and anti-neutrons.
I am generated in particle accelerators. Electrically charged particles are accelerated there to high energies. When other particles collide, quarks and anti-quarks can be created.
Like all quarks, I too am a group being and bind with one quark to form a group of two (called a «meson») or with two other anti-quarks to form a group of three (called a «baryon»)
I am too short-lived to form mesons or baryons. My properties are extensively studied as a means to discriminate between competing theories of new physics beyond the Standard Model.